JP2021057576A - Transformer - Google Patents

Abstract

To provide a transformer with reduced no-load loss.SOLUTION: A transformer includes an iron core constituted by an Fe-based amorphous alloy ribbon in which, on at least one surface of the Fe-based amorphous alloy ribbon, there are a plurality of point-row laser irradiation marks provided along the direction orthogonal to the casting direction of the Fe-based amorphous alloy ribbon, the line spacing between dotted laser irradiation marks is d1 (mm), the spot spacing of the dotted laser irradiation marks is d2 (mm), the spot spacing is 0.10 mm to 0.50 mm, the number density D (D=(1/d1)×(1/d2)) of the laser irradiation mark is 0.05 pieces/mm2 to 0.50 pieces/mm2, the iron loss of the single plate at a frequency of 50 Hz, a frequency is 60 Hz, and a magnetic flux density of 1.45 T is 0.150 W/kg or less, and a wiring wound around the iron core.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to a transformer including an iron core configured by using an Fe-based amorphous alloy strip and a winding wound around the iron core.

Transformers have a wide variety of configurations, from small to large, and are used in all aspects of the living environment. And, due to the large amount of electricity used, it is one of the major causes of power loss, and there is always a demand to suppress the loss in the transformer. For this reason, countries around the world have established standards to control the loss. Typical examples are Japanese Industrial Standards JIS C 4304: 2013 and JIS C 4306: 2013, US DOE Standards US Department of Energy 10 CFR Part 431.196, EU Standards Communications Regulation (EU) No.548 / 2014, There are Chinese national standard GB 20052-2013, Indian standard IS 1180 (Part 1): 2018, etc., all of which have stricter permissible losses or energy efficiency with each regular revision work. For this reason, high-efficiency transformers with less loss have become widespread in a form corresponding to these standards.

A transformer is composed of an iron core and windings as main components, and generally, grain-oriented electrical steel sheets are often used for the iron core. However, as a material having a lower loss than the grain-oriented electrical steel sheet, there is also an Fe-based amorphous alloy strip, and an iron core using this Fe-based amorphous alloy strip is also used.
Transformer losses can be broadly divided into no-load loss (iron loss), which occurs in the iron core and always occurs in a fixed amount regardless of the load current, and in proportion to the square of the load current, which occurs in the winding. There is a load loss (copper loss). Studies to reduce the loss have been repeated, and although the loss has been improved, further reduction of the loss is required.

Several methods have been proposed to reduce the no-load loss of the transformer.
In JP-A-2017-54896, in order to obtain an efficient iron core with reduced no-load loss, the joint structure on the inner peripheral side is an overlap joint, the joint structure on the outer peripheral side is a step wrap joint, and the inner peripheral side A wound iron core using an amorphous material in which the ratio of the iron cores of the arranged overlapping structures is 32 to 62% is adopted.
Japanese Patent Application Laid-Open No. 2008-71982 describes a transformer provided with an iron core obtained by forming an amorphous alloy thin film into a plurality of layers in an annular shape and a winding for excitation, and is formed on the surface of the amorphous alloy thin film forming the iron core. An insulating thin film is formed, and by forming the insulating thin film on the surface of the amorphous alloy strip, it is possible to suppress an increase in eddy current loss and reduce a no-load loss of a transformer.
Japanese Patent Laying-Open No. 2005-72160 has a structure in which an amorphous alloy strip and an electromagnetic steel sheet are simultaneously used as the magnetic material of the wound iron core in a three-phase five-legged wound iron core transformer. Specifically, in a three-phase five-legged winding core transformer, the wound core that is linked with only one outer winding is an electromagnetic steel plate, and the central winding core that is linked with two windings is an amorphous alloy thin band. It is a structure to be. This eliminates the need for reinforcing materials that hold down the windings, and by making the structure compact, the man-hours and material costs for assembly work are reduced, and the no-load loss is reduced compared to when the magnetic material is only electromagnetic steel sheets. Provided are alloy thin band wound steel cores and three-phase five-legged steel core transformers.

In addition, efforts are being made to reduce the loss of the Fe-based amorphous alloy strip used as the material for the iron core.
For example, as a method of reducing the abnormal eddy current loss of the Fe-based amorphous alloy strip, a method of mechanically scratching the surface of the Fe-based amorphous alloy strip, or irradiating the surface of the Fe-based amorphous alloy strip with laser light. A laser scribing method or the like is known in which magnetic domains are subdivided by locally melting and quenching and solidifying.
As a laser scribing method, for example, in Japanese Patent Publication No. 3-32886, the surface of the amorphous alloy strip is locally and instantaneously melted by irradiating the pulse laser in the width direction of the amorphous alloy strip, and then quenching is performed. A method of subdividing a magnetic region by forming a series of solidified and amorphized spots is disclosed.
Japanese Unexamined Patent Publication No. 61-258404 discloses that while the surface temperature of the thin band is 300 ° C. or higher, the laser beam is irradiated while sweeping in the width direction of the thin band.

According to Japanese Patent Publication No. 2-53935, by locally heating the thin band, the angle θ formed in the longitudinal direction of the thin band at intervals of 2 to 100 mm and in the width direction of the thin band is 30 ° or less. At the same time as forming the strip-shaped crystallization regions lined up in a row, the ratio d / D of the average depth d in the plate thickness direction and the thickness D of the thin band of each region is 0.1 or more. At the same time, it is disclosed that the ratio of these regions in the thin band is 8% by volume or less.
Japanese Patent Application Laid-Open No. 61-29103 states that the beam diameter is 0.5 mmφ or less in order to sufficiently bring out the performance of an amorphous alloy having a plate thickness (40 to 80 μm) larger than the plate thickness (20 to 30 μm) of the conventional material. It is disclosed to irradiate a pulsed laser beam focused on. Specifically, a YAG laser is applied to an amorphous strip having a plate width of 50 mm and a plate thickness of 65 μm under the conditions of a frequency of 400 Hz, a beam diameter of 0.2 mmφ, an output of 5 W, a beam sweep speed of 10 cm / see, and a dot spacing of 5 mm. It is described to irradiate.

JP-A-2017-54896 Japanese Unexamined Patent Publication No. 2008-71982 Japanese Unexamined Patent Publication No. 2005-72160 Special Fair 3-32886 Gazette Japanese Unexamined Patent Publication No. 61-258404 Special Fair 2-53935 Gazette Japanese Unexamined Patent Publication No. 61-29103

As described above, the main loss of the transformer is the no-load loss generated in the iron core and the load loss generated in the winding. In order to reduce the no-load loss of the transformer, it is conceivable to use an Fe-based amorphous alloy strip having a small iron loss. In particular, in the case of distribution transformers, Takagi, Yamamoto, Yamaji: "Evaluation of Amorphous Transformers Using Pole Transformer Load Pattern Creation Model" P885-892, Denki B, Vol. 128, No. 6, 2008, Alternatively, as described in Final Report, LOT 2: Distribution and power transformers Tasks 1-7 2010 / ETE / R / 106, January 2011, the average equivalent load factor corresponding to the effective value of the load factor throughout the year is 15. It is known that the ratio is as low as about%, and a transformer using an Fe-based amorphous alloy strip with a small no-load loss is extremely effective from the viewpoint of _{energy saving and CO 2 emission reduction.}

Fe-based amorphous alloy strips for the iron core of transformers are 2 of ordinary material and high magnetic flux density material as shown in Tables 1 and 2 of JIS C2534: 2017 (corresponding IEC standard IEC60404-8-11). It is roughly classified into types, and there are 16 types of each based on the maximum value of the iron loss and the minimum value of the space factor. It has the smallest iron loss, and the maximum value of iron loss at a frequency of 50 Hz and a magnetic flux density of 1.3 T is 0.08 W / kg, and the maximum value of iron loss at a frequency of 60 Hz and a magnetic flux density of 1.3 T is 0.11 W / kg. It is kg. However, in order to obtain a transformer with higher efficiency, it is necessary to use an Fe-based amorphous alloy strip having a smaller iron loss for the iron core.

The laser scribing method described above has been attempted to reduce the iron loss of the amorphous alloy strip, but the iron loss has reached the minimum iron loss values listed in Tables 1 and 2 of JIS C2534: 2017. No (see, for example, Examples in JP-A-3-32886, JP-A-61-258404, JP-A-2-53935, and JP-A-61-29103).

In addition, the surface morphology of the amorphous alloy strip may be significantly deformed by laser irradiation. When the deformation is large, the space factor of the amorphous alloy thin band becomes low when the iron core is formed by winding or laminating the amorphous alloy thin band. Such a large deformation of the surface morphology of the amorphous alloy strip is not a preferable morphology in terms of iron core characteristics. Further, when the crystallized region is formed by locally heating the thin band, the desired characteristics cannot be obtained due to the crystallization.

The present disclosure is a transformer having an iron core configured by using an Fe-based amorphous alloy strip showing an iron loss value smaller than the minimum iron loss value shown in Tables 1 and 2 of JIS C2534: 2017. Therefore, it is an object to provide a transformer with reduced no-load loss.

Specific means for solving the above problems include the following aspects.
<1> A plurality of point-row laser irradiation marks provided along a direction orthogonal to the casting direction of the Fe-based amorphous alloy strip are provided on at least one surface of the Fe-based amorphous alloy strip.
Among the plurality of point-series laser irradiation marks, the center line spacing in the central portion in the width direction orthogonal to the casting direction between the point-series laser irradiation marks adjacent to each other is defined as the line spacing, and the point-series laser irradiation is performed. When the distance between the center points of the individual laser irradiation marks constituting the marks is the spot spacing, the spot spacing is 0.10 mm to 0.50 mm, the line spacing is d1 (mm), and the spot spacing is defined as the spot spacing. When d2 (mm) and the number density D of the laser irradiation marks is D = (1 / d1) × (1 / d2), the number density D of the laser irradiation marks is 0.05 pieces / mm ² to. Using a Fe-based amorphous alloy strip having a frequency of 0.50 pieces / mm ² and an iron loss of 0.150 W / kg or less at a frequency of 60 Hz and a magnetic flux density of 1.45 T in the single plate of the Fe-based amorphous alloy strip. A transformer including an iron core configured in the above direction and a winding wound around the iron core.
<2> The transformer is a single-phase transformer, and the no-load loss per weight of the iron core is 0.15 W / kg or less at 50 Hz, or 0.19 W / kg or less at 60 Hz, <1>. The transformer described.
<3> The transformer is a three-phase transformer, and the no-load loss per weight of the iron core is 0.19 W / kg or less at 50 Hz or 0.24 W / kg or less at 60 Hz, <1>. The transformer described.
<4> The transformer according to any one of <1> to <3>, wherein the rated capacity of the transformer is 10 kVA or more.
<5> The transformer according to any one of <1> to <4>, wherein the line spacing d1 is 10 mm to 60 mm.
<6> The ratio of the length of the point-row laser irradiation mark in the width direction to the total length of the Fe-based amorphous alloy strip in the width direction is from the center in the width direction to both ends in the width direction, respectively. The transformer according to any one of <1> to <5>, which is in the range of 10% to 50%.
<7> The transformer according to any one of <1> to <6>, wherein the thickness of the Fe-based amorphous alloy strip is 18 μm to 35 μm.
<8> The Fe-based amorphous strip is composed of Fe, Si, B, and impurities, and the Fe content is 78 atomic% or more when the total content of Fe, Si, and B is 100 atomic%. The transformer according to any one of <1> to <7>, wherein the content of B is 10 atomic% or more, and the total content of B and Si is 17 atomic% to 22 atomic%.
<9> The Fe-based amorphous alloy strip has a free solidification surface and a roll surface, and the maximum cross-sectional height Rt of the free solidification surface excluding the point-row laser irradiation scar portion is 3.0 μm or less. The transformer according to any one of <1> to <8>.
<10> The dotted laser irradiation marks are the six central regions in the width direction, excluding the two regions at both ends from the eight regions obtained by dividing the width direction of the Fe-based amorphous alloy strip into eight equal parts. The transformer according to any one of <1> to <9>, which is formed at least in the region.

According to one aspect of the present disclosure, a transformer with reduced no-load loss is provided.

It is the schematic which shows an example of the transformer of this embodiment. It is the schematic which shows another example of the transformer of this embodiment. It is the schematic which shows still another example of the transformer of this embodiment. It is a schematic diagram which shows an example of the Fe-based amorphous alloy strip of this embodiment. It is a graph which shows the relationship between the magnetic flux density and iron loss when the spot interval is changed. It is a graph which shows the relationship between the magnetic flux density and the exciting power when the spot interval is changed.

In the present specification, the numerical range represented by using "~" means a range including the numerical values before and after "~" as the lower limit value and the upper limit value. In the numerical range described stepwise in the present specification, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical range described stepwise. .. Further, in the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples.
In the present specification, the term "process" is included in this term not only as an independent process but also as long as the intended purpose of the process is achieved even if it cannot be clearly distinguished from other processes. ..
In the present specification, the Fe-based amorphous alloy strip refers to a strip made of Fe-based amorphous alloy.
In the present specification, the Fe-based amorphous alloy refers to an amorphous alloy containing Fe (iron) as a main component. Here, the principal component refers to the component having the highest content ratio (mass%).
Hereinafter, embodiments relating to the present disclosure will be described. The present disclosure is not limited to the embodiments described below, and can be appropriately modified within the scope of the technical idea.

The transformer of the embodiment according to the present disclosure is
The Fe-based amorphous alloy strip has a plurality of dot-row laser irradiation marks provided along a direction orthogonal to the casting direction of the Fe-based amorphous alloy strip on at least one surface of the Fe-based amorphous alloy strip, and the plurality of dot-row lasers are provided. Among the irradiation marks, the center line spacing in the central portion in the width direction orthogonal to the casting direction between the point-row laser irradiation marks adjacent to each other is defined as the line spacing, and the individual lasers constituting the point-series laser irradiation marks. When the center point spacing of the irradiation marks is the spot spacing, the spot spacing is 0.10 mm to 0.50 mm, the line spacing is d1 (mm), the spot spacing is d2 (mm), and the above. When the number density D of the laser irradiation marks is D = (1 / d1) × (1 / d2), the number density D of the laser irradiation marks is 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ^2. And
The iron core formed by using the Fe-based amorphous alloy thin band having an iron loss of 0.150 W / kg or less at a frequency of 60 Hz and a magnetic flux density of 1.45 T in a single plate of the Fe-based amorphous alloy thin band, and the iron core. A transformer with a wound winding.

Further, the Fe-based amorphous alloy strip has reduced iron loss at a frequency of 50 Hz and a magnetic flux density of 1.45 T on a single plate. The Fe-based amorphous alloy strip preferably has an iron loss of 0.120 W / kg or less at a frequency of 50 Hz and a magnetic flux density of 1.45 T on a single plate.
The Fe-based amorphous alloy strip has an iron loss of 0.08 W / kg or less at a frequency of 50 Hz and a magnetic flux density of 1.3 T, or an iron loss of 0.11 W / kg or less at a frequency of 60 Hz and a magnetic flux density of 1.3 T. Is preferable.

Further, as the iron core in the present embodiment, it is preferable to use a circumferential iron core in which a plurality of Fe-based amorphous alloy strips are bent and wound in an overlapping manner. Further, it is preferable to use a plurality of these circular iron cores in combination. Further, as the iron core, a stacked iron core formed by stacking a plurality of Fe-based amorphous alloy thin strips may be used, or a wound iron core formed by winding a Fe-based amorphous alloy thin strip may be used.
Further, the transformer of the present embodiment is preferably a single-phase transformer or a three-phase transformer, and the rated capacity of the transformer is preferably 10 kVA or more.
Further, in the case of a single-phase transformer, the no-load loss per weight of the iron core is preferably 0.15 W / kg or less at 50 Hz or 0.19 W / kg or less at 60 Hz.
Further, in the case of a three-phase transformer, the no-load loss per weight of the iron core is preferably 0.19 W / kg or less at 50 Hz or 0.24 W / kg or less at 60 Hz.

Example 1
FIG. 1 shows an example of the configuration of the iron core and the winding of the transformer of the present embodiment. The transformer shown in FIG. 1 includes a circumferential iron core 1 in which a plurality of laminated Fe-based amorphous alloy strips are bent and wound in an overlapping manner, and a winding 2 wound around the iron core. The winding 2 is incorporated into the iron core in a state where the iron core is open before overlapping the iron cores. The iron core 1 of the first embodiment is composed of one circumferential iron core (single-phase two-leg winding iron core). The main characteristics and weight of an oil-filled transformer (hereinafter referred to as Example 1) having a single-phase 50 Hz and a rated capacity of 10 kVA according to the present invention based on JIS C 4304: 2013 using the iron core 1 of this embodiment are the same as those of the conventional example 1. The comparison is shown in Table 1. Here, since the Fe-based amorphous alloy strip used in Example 1 has the above characteristics, the iron core material is described as 25AMP06-88 according to the definition of "5 Amorphous band type symbols" in JIS C 2534: 2017. did. The Fe-based amorphous alloy strip used in Conventional Example 1 is 25AMP08-88. The characteristics of Examples 1 to 8 below are numerical values obtained by analysis by simulation.

The Fe-based amorphous alloy strip used in Example 1 has a thickness of 25 μm and a width of 142.2 mm, and has dotted laser irradiation marks formed on the free solidifying surface, and the line spacing of the point row laser irradiation marks. Is 20 mm, the spot interval is 0.20 mm, the number density D of the laser irradiation marks is 0.25 pieces / mm ² , the iron loss at a frequency of 50 Hz and a magnetic flux density of 1.45 T is 0.083 W / kg. The iron loss at a frequency of 60 Hz and a magnetic flux density of 1.45 T is 0.105 W / kg.
Further, the Fe-based amorphous alloy strip used in Conventional Example 1 has a thickness of 25 μm and a width of 142.2 mm, no laser irradiation marks are formed, and iron loss at a frequency of 50 Hz and a magnetic flux density of 1.45 T is 0. The iron loss at 130 W / kg, frequency 60 Hz, and magnetic flux density 1.45 T is 0.167 W / kg.
In the first embodiment and the first conventional example, the number of stacked iron cores 1 is 1875, and the weight thereof is shown in Table 1.
The primary winding of this transformer is a copper wire with a diameter of 0.9 mm and is wound for 3143 turns, and the secondary winding is a flat wire of 3.2 mm x 6.0 mm made of aluminum. The windings of 100 turns were connected in parallel.

From Table 1, in Example 1, the no-load loss per weight of the iron core is 0.149 W / kg, which is about 25% less than the no-load loss per weight of the iron core of Conventional Example 1. You can see that.
Correspondingly, the ratio of the conventional example 1 to the energy consumption efficiency standard value defined by JIS C 4304: 2013 is 0.73 (described in "Energy consumption efficiency ratio" in Table 1. The same shall apply hereinafter). On the other hand, in Example 1, it was improved to 0.70, and _{it can be seen that the annual CO 2} emission is also improved by about 15% when the average equivalent load ratio of the distribution transformer is 15%. _{This can be seen from the fact that the “annual CO 2} emission ratio when the load factor is 15%” shown in Table 1 is 0.85 (the same applies hereinafter).

Example 2
As a second embodiment of the transformer having the iron core and winding configuration shown in FIG. 1, a single-phase 60 Hz, rated capacity 10 kVA oil-filled transformer according to the present invention in accordance with JIS C 4304: 2013 (hereinafter referred to as , The main characteristics and weight of Example 2) are shown in Table 2 in comparison with Conventional Example 2.
The Fe-based amorphous alloy strip used in Example 2 is the same as that of Example 1, and the Fe-based amorphous alloy strip used in Conventional Example 2 is the same as that of Conventional Example 1.
In the second embodiment and the second conventional example, the number of stacked iron cores 1 is 1785, and the weight thereof is shown in Table 2.
The primary winding of this transformer is a copper wire with a diameter of 0.9 mm and is wound for 2776 turns, and the secondary winding is a flat wire of 2.6 mm x 6.0 mm made of aluminum. The 88-turn winding was connected in parallel.

From Table 2, in Example 2, the no-load loss per weight of the iron core was 0.189 W / kg, which was reduced by about 27% from the no-load loss per weight of the iron core of Conventional Example 2 of 0.259 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 2 to the energy consumption efficiency standard value defined in JIS C 4304: 2013 is 0.72, whereas that of the second embodiment is improved to 0.68. _{It can be seen that the annual CO 2} emissions are also improved by about 18% when the average equivalent load ratio of the distribution transformer is 15%.

Example 3
As a third embodiment of the transformer having the iron core and winding configuration shown in FIG. 1, a single-phase 50 Hz, rated capacity 30 kVA oil-filled transformer according to the present invention in accordance with JIS C 4304: 2013 (hereinafter referred to as , The main characteristics and weight of Example 3) are shown in Table 3 in comparison with the conventional example 3.
The Fe-based amorphous alloy strip used in Example 3 has a thickness of 25 μm and a width of 213.4 mm, and has dotted laser irradiation marks formed on the free solidifying surface, and the line spacing of the point sequence laser irradiation marks. Is 20 mm, the spot interval is 0.20 mm, the number density D of the laser irradiation marks is 0.25 pieces / mm ² , and the iron loss at a frequency of 50 Hz and a magnetic flux density of 1.45 T is 0.085 W /. The iron loss at kg, frequency 60 Hz, and magnetic flux density 1.45 T is 0.108 W / kg.
Further, the Fe-based amorphous alloy strip used in Conventional Example 3 has a thickness of 25 μm and a width of 213.4 mm, no laser irradiation marks are formed, and iron loss at a frequency of 50 Hz and a magnetic flux density of 1.45 T is 0. The iron loss at 132 W / kg, frequency 60 Hz, and magnetic flux density 1.45 T is 0.168 W / kg.
In the third embodiment and the third conventional example, the circumferential iron core 1 has a number of laminated iron cores of 3015, and the weight thereof is shown in Table 3.
The primary winding of this transformer uses a copper wire with a diameter of 1.4 mm and is wound for 1509 turns, and the secondary winding uses a flat wire of 3.2 mm × 15 mm made of aluminum and has 44 turns each. The windings of were connected in parallel.

From Table 3, in Example 3, the no-load loss per weight of the iron core was 0.138 W / kg, which was reduced by about 30% from the no-load loss per weight of the iron core of Conventional Example 3 of 0.197 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 3 to the energy consumption efficiency standard value defined in JIS C 4304: 2013 is 0.72, whereas that of the third example is improved to 0.68. _{It can be seen that the annual CO 2} emissions are also improved by about 18% when the average equivalent load ratio of the distribution transformer is 15%. Further, the no-load loss per weight of the iron core in Example 1 was 0.149 W / kg, whereas in Example 3, it was 0.138 W / kg, which is an improvement of 0.011 W / kg. The reason for this is that due to the increase in size of the iron core, the ratio of the length of the curved portion to the magnetic path length of the iron core becomes small, and the no-load loss due to the residual stress of the curved portion of the iron core is suppressed.

Example 4
As a fourth embodiment of the transformer having the iron core and winding configuration shown in FIG. 1, a single-phase 60 Hz, rated capacity 30 kVA oil-filled transformer according to the present invention in accordance with JIS C 4304: 2013 (hereinafter referred to as , The main characteristics and weight of Example 4) are shown in Table 4 in comparison with the conventional example 4.
The Fe-based amorphous alloy strip used in Example 4 is the same as that of Example 3, and the Fe-based amorphous alloy strip used in Conventional Example 4 is the same as that of Conventional Example 3.
In the fourth embodiment and the fourth conventional example, the circumferential iron core 1 has 2715 laminated iron cores, and the weight thereof is shown in Table 4.
The primary winding of this transformer is a copper wire with a diameter of 1.3 mm and is wound for 1509 turns, and the secondary winding is a flat wire of 4.0 mm x 13 mm made of aluminum and has 44 turns each. The windings of were connected in parallel.

From Table 4, in Example 4, the no-load loss per weight of the iron core was 0.180 W / kg, which was reduced by about 30% from the no-load loss per weight of the iron core of Conventional Example 4 of 0.256 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 4 to the energy consumption efficiency standard value defined in JIS C 4304: 2013 is 0.72, whereas that of the fourth example is improved to 0.67. _{It can be seen that the annual CO 2} emissions are also improved by about 19% when the average equivalent load ratio of the distribution transformer is 15%. Further, the no-load loss per weight of the iron core in Example 2 was 0.189 W / kg, whereas in Example 4, it was 0.180 W / kg, which is an improvement of 0.009 W / kg. This is reduced for the reasons described in Example 3 above.

Example 5
FIG. 2 shows another example of the configuration of the iron core and the winding of the transformer of the present embodiment. The transformer shown in FIG. 2 is a three-phase three-legged iron core (three orbital iron cores) in which a plurality of laminated Fe-based amorphous alloy strips are bent and overlapped and wound by a circular iron core 1. Combination) and three sets of windings 2 wound around the iron core. The main characteristics and weight of an oil-filled transformer (hereinafter referred to as Example 5) having a three-phase 50 Hz and a rated capacity of 100 kVA according to the present invention based on JIS C 4304: 2013 using the iron core of this embodiment are the same as those of the conventional example 5. A comparison is shown in Table 5.
The Fe-based amorphous alloy strip used in Example 5 is the same as in Example 3, and the Fe-based amorphous alloy strip used in Conventional Example 5 is the same as in Conventional Example 3.
In Example 5 and Conventional Example 5, each of the circumferential iron cores 1 has a number of stacked 3480 sheets, and the weight thereof (total of the three circular iron cores) is shown in Table 5.
The primary winding of this transformer uses a copper wire with a diameter of 2.2 mm and is wound with a star-shaped connection for 653 turns, and the secondary winding uses a 0.4 mm x 247 mm sheet made of aluminum and is triangular. The winding was 36 turns.

From Table 5, in Example 5, the no-load loss per weight of the iron core was 0.188 W / kg, which was reduced by about 30% from the no-load loss per weight of the iron core of Conventional Example 5 of 0.269 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 5 to 0.78 is 0.78 with respect to the energy consumption efficiency standard value defined in JIS C 4304: 2013, but in the fifth embodiment, it can be improved to 0.73. _{It can be seen that the annual CO 2} emissions are also improved by about 20% when the average equivalent load ratio of the distribution transformer is 15%.

Example 6
As another example of the transformer having the iron core and winding configuration shown in FIG. 2, an oil-filled transformer according to the present invention in accordance with JIS C 4304: 2013, having a rated capacity of 100 kVA and a three-phase 60 Hz (hereinafter referred to as a transformer). Table 6 shows the main characteristics and weight of Example 6) in comparison with Conventional Example 6.
The Fe-based amorphous alloy strip used in Example 6 is the same as in Example 3, and the Fe-based amorphous alloy strip used in Conventional Example 6 is the same as in Conventional Example 3. In the 6th embodiment and the 6th conventional example, the circumferential iron core 1 has 2895 layers, and the weight thereof is shown in Table 6.
The primary winding and the secondary winding of this transformer are the same as those in the fifth embodiment and the fifth embodiment.

From Table 6, in Example 6, the no-load loss per weight of the iron core was 0.238 W / kg, which was reduced by about 30% from the no-load loss per weight of the iron core of Conventional Example 6 of 0.339 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 6 is 0.81 to the energy consumption efficiency standard value defined in JIS C 4304: 2013, whereas that of the sixth example is improved to 0.77. _{It can be seen that the annual CO 2} emissions are also improved by about 19% when the average equivalent load ratio of the distribution transformer is 15%.

Example 7
As another example of the transformer having the iron core and winding configuration shown in FIG. 2, a three-phase 50 Hz, rated capacity 500 kVA oil-filled transformer according to the present invention in accordance with JIS C 4304: 2013 (hereinafter, Table 7 shows the main characteristics and weight of Example 7) of the present invention in comparison with Conventional Example 7.
The Fe-based amorphous alloy strip used in Example 7 is the same as in Example 3, and the Fe-based amorphous alloy strip used in Conventional Example 7 is the same as in Conventional Example 3.
In the 7th embodiment and the 7th conventional example, the circular iron core 1 has 5685 laminated pieces of the 7th embodiment and 5955 pieces of the conventional example 7, and the weights (total of the three circular iron cores) are shown in the table. Shown in 7.
The primary winding of Example 7 uses a 3.5 mm × 4.5 mm flat copper wire and is wound with a star-shaped connection for 399 turns, and the secondary winding is made of aluminum and has a thickness of 1.3 mm × 438 mm. A sheet was used, and the winding was made with a triangular connection for 22 turns. Further, the primary winding of Conventional Example 7 uses a 3.2 mm × 5.0 mm flat copper wire and is wound 381 turns with a star-shaped connection, and the secondary winding is made of aluminum 1.4 mm × 383 mm. The winding was made with a triangular connection for 21 turns.

From Table 7, in Example 7, the no-load loss per weight of the iron core was 0.172 W / kg, which was reduced by about 30% from the no-load loss per weight of the iron core of Conventional Example 7 of 0.246 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 7 to 0.93 is 0.93 with respect to the energy consumption efficiency standard value defined in JIS C 4304: 2013, whereas in the seventh embodiment, it can be improved to 0.90. _{It can be seen that the annual CO 2} emissions are also improved by about 16% when the average equivalent load ratio of the distribution transformer is 15%. Further, the no-load loss per weight of the iron core in Example 5 was 0.188 W / kg, whereas in Example 7, it was 0.172 W / kg, which is an improvement of 0.016 W / kg. The reason for this is that due to the increase in size of the iron core, the ratio of the length of the curved portion to the magnetic path length of the iron core becomes small, and the no-load loss due to the residual stress of the curved portion of the iron core is suppressed.

Example 8
FIG. 3 shows another example of the configuration of the iron core and the winding of the transformer of the present embodiment. This transformer consists of a three-phase five-legged iron core, which is a combination of a plurality of laminated Fe-based amorphous alloy strips bent and wound in an overlapping manner, and three sets wound around the iron core. The winding 2 is provided. The main characteristics and weight of an oil-filled transformer (hereinafter referred to as Example 8) having a three-phase 50 Hz and a rated capacity of 1000 kVA according to the present invention based on JIS C 4304: 2013 using the iron core of this embodiment are the same as those of the conventional example 8. A comparison is shown in Table 8.
The Fe-based amorphous alloy strip used in Example 8 is the same as in Example 3, and the Fe-based amorphous alloy strip used in Conventional Example 8 is the same as in Conventional Example 3.
In the 8th embodiment and the 8th conventional example, the circumferential iron core 1 is formed by stacking two iron cores having a stacking number of 2610 in the vertical direction of FIG. 3, and the weight thereof (of the eight circular iron cores). Total) is shown in Table 8.
The primary winding of Example 8 uses a 2.8 mm × 7.0 mm flat copper wire and is wound 377 turns with a triangular connection, and the secondary winding is a 3.0 mm × 305 mm sheet made of aluminum. Was used to make a 12-turn winding with a triangular connection. Further, the primary winding of Conventional Example 8 uses a flat copper wire of 2.8 mm × 7.0 mm and is wound for 377 turns with a triangular connection, and the secondary winding is made of aluminum of 3.2 mm × 306 mm. A sheet was used, and a 12-turn winding was made with a triangular connection.

From Table 8, in Example 8, the no-load loss per weight of the iron core is 0.188 W / kg, which is about 30% less than the no-load loss per weight of the iron core of Conventional Example 8 of 0.269 W / kg. You can see that.
Correspondingly, the ratio of the conventional example 8 is 0.999 to the energy consumption efficiency standard value defined in JIS C 4304: 2013, whereas in the example 8, it can be improved to 0.996. _{It can be seen that the annual CO 2} emissions are also improved by about 15% when the average equivalent load ratio of the distribution transformer is 15%.

As described above, the transformer of the present disclosure can reduce no-load loss, and is particularly effective in reducing _{loss and CO 2 emissions of distribution transformers having a low average equivalent load factor.} Is. In this embodiment, the application to the wound iron core transformer has been described in detail, but it goes without saying that the effect of reducing the no-load loss can be obtained even in the case of the stacked iron core transformer.

[Fe-based amorphous alloy thin band]
The Fe-based amorphous alloy strip used in this embodiment will be described in detail below.
As described above, the Fe-based amorphous alloy strip used in the present embodiment is a sequence of points provided on at least one surface of the Fe-based amorphous alloy strip along a direction orthogonal to the casting direction of the Fe-based amorphous alloy strip. Has multiple laser irradiation marks
Of a plurality of point-row laser irradiation marks, the center line spacing in the central portion in the width direction orthogonal to the casting direction between the point-row laser irradiation marks adjacent to each other is set as the line spacing to form the point-series laser irradiation marks. When the center point spacing of each laser irradiation mark is the spot spacing, the spot spacing is 0.10 mm to 0.50 mm, the line spacing is d1 (mm), the spot spacing is d2 (mm), and the laser. When the number density D of the irradiation marks is D = (1 / d1) × (1 / d2), the number density D of the laser irradiation marks is 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ² . , Fe-based amorphous alloy thin band single plate has an iron loss of 0.150 W / kg or less at a frequency of 60 Hz and a magnetic flux density of 1.45 T.
Further, the Fe-based amorphous alloy strip has reduced iron loss at a frequency of 50 Hz and a magnetic flux density of 1.45 T on a single plate.
Further, the Fe-based amorphous alloy strip has reduced iron loss at a frequency of 50 Hz and a magnetic flux density of 1.3 T, or iron loss at a frequency of 60 Hz and a magnetic flux density of 1.3 T.

The Fe-based amorphous alloy strip (hereinafter, also simply referred to as “thin strip”) of the present disclosure has the above configuration, so that iron loss under the condition of a magnetic flux density of 1.45 T is reduced, and the magnetic flux density is 1. The increase in exciting power under the condition of 45T is suppressed.
First, the effect of reducing iron loss under the condition of a magnetic flux density of 1.45 T will be described. As described above, the Fe-based amorphous alloy strip of the present disclosure has a dotted laser irradiation mark composed of a plurality of laser irradiation marks on at least one surface. In the Fe-based amorphous alloy strip of the present disclosure, the magnetic domains are subdivided by having the dotted laser irradiation marks, and as a result, the iron loss under the condition of the magnetic flux density of 1.45 T is reduced.
As described above, forming the dotted laser irradiation marks on the Fe-based amorphous alloy strip itself contributes to reducing the iron loss under the condition of the magnetic flux density of 1.45 T.

Next, the effect of suppressing the increase in the exciting power under the condition of the magnetic flux density of 1.45 T will be described. Although the details will be described later, the present inventors have found that forming laser irradiation marks on the Fe-based amorphous alloy strip may cause an increase in exciting power under the condition of a magnetic flux density of 1.45 T. It was. An increase in the exciting power under the condition of a magnetic flux density of 1.45 T is not desirable because it causes a decrease in the magnetic flux density B0.08.
In this regard, in the Fe-based amorphous alloy ribbon of the present disclosure, among the plurality of dot-row laser irradiation marks provided in the casting direction of the strip, the dot-row laser irradiation marks adjacent to each other are oriented in the casting direction. The line spacing, which is the center line spacing in the central portion in the orthogonal direction (hereinafter referred to as the width direction), is d1 (mm), and the spot spacing, which is the center point spacing of the individual laser irradiation marks constituting the point-row laser irradiation marks. Is d2 (mm). When the spot interval is 0.10 mm to 0.50 mm and the number density D of the laser irradiation marks is D = (1 / d1) × (1 / d2), the number density D of the laser irradiation marks is 0. It is 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ² . In short, in the Fe-based amorphous alloy strip of the present disclosure, the spot spacing and line spacing of the laser irradiation marks are widened to some extent, and the number of laser irradiation marks is reduced to some extent (that is, the number density of the laser irradiation marks is reduced to some extent. ing).
In the Fe-based amorphous alloy strip of the present disclosure, the spot spacing and the line spacing of the laser irradiation marks are widened to some extent, and the number density of the laser irradiation marks is reduced to some extent, so that the exciting power is increased under the condition of the magnetic flux density of 1.45T. It is suppressed.
If the point-row laser irradiation mark does not extend to the central part in the width direction of the thin band, the line spacing extends the point-row laser irradiation mark to a position extending to the central part in the width direction of the thin band. Can be measured.
Further, the decrease in the magnetic flux density B0.08 due to the increase in the exciting power is also suppressed.

As described above, in the Fe-based amorphous alloy strip of the present disclosure, the iron loss under the condition of the magnetic flux density of 1.45T is reduced, and the increase of the exciting power under the condition of the magnetic flux density of 1.45T is suppressed.
Hereinafter, the above-mentioned effect of the Fe-based amorphous alloy strip of the present disclosure will be described in more detail in comparison with the prior art.

Conventionally, iron loss and exciting power have generally been measured under the condition of a magnetic flux density of 1.3 T.
For example, in the above-mentioned Examples of JP-A-61-29103, a YAG laser is applied to the free-solidified surface of the Fe-based amorphous alloy strip with a dot spacing of 5 mm (the number density D at this time is 0). It is disclosed that the iron loss under the condition of the magnetic flux density of 1.3 T is reduced by (8 pieces / mm ^2).
Further, in the fourth embodiment of the above-mentioned International Publication No. 2011/030907, when the free-solidified surface of the Fe-based amorphous alloy strip is irradiated with laser light to form recess rows at intervals of 5 mm in the longitudinal direction ( At this time, the number density D is 0.8 pieces / mm ² ), and the ratio t1 / T of the depth t1 of the recess and the thickness T of the thin band is 0.025 to 0.18. It is disclosed that the iron loss and the apparent power under the condition of the magnetic flux density of 1.3 T are reduced when the condition is satisfied. The apparent power in International Publication No. 2011/030907 corresponds to the exciting power referred to in the present specification.
Further, in the first embodiment of the above-mentioned International Publication No. 2012/102379, wavy irregularities are formed on the free solidified surface of the Fe-based amorphous alloy strip, and the wavy irregularities are arranged at substantially regular intervals in the longitudinal direction. It is disclosed that when the valley portion is provided in the width direction and the average amplitude of the valley portion is 20 mm or less, the iron loss and the exciting power under the condition of the magnetic flux density of 1.3 T are reduced.

However, in recent years, from the viewpoint of miniaturization of transformers manufactured by using Fe-based amorphous alloy strips, the condition of magnetic flux density 1.45T is not the condition of iron loss and exciting power under the condition of magnetic flux density 1.3T. It may be required to reduce the iron loss and the exciting power in the above.
In this regard, according to the study by the present inventors, a certain Fe-based amorphous alloy strip (specifically, a Fe-based amorphous alloy strip having a high number density of laser irradiation marks) has a magnetic flux density of 1.3 T. It was found that even if the exciting power was reduced to some extent when measured under the conditions, the exciting power was significantly increased when measured under the condition of the magnetic flux density of 1.45 T.
Hereinafter, this point will be described in detail with reference to FIGS. 5 and 6.

FIG. 5 shows an unlaser-processed Fe-based amorphous alloy strip, a laser-processed Fe-based amorphous alloy strip with a spot spacing of 0.05 mm, and a laser-processed Fe-based amorphous alloy strip with a spot spacing of 0.10 mm. It is a graph which shows the relationship between the magnetic flux density, and iron loss about four kinds of Fe-based amorphous alloy thin strips which were laser-processed with a band and a spot interval of 0.20 mm.
FIG. 6 is a graph showing the relationship between the magnetic flux density and the exciting power.

In FIGS. 5 and 6, the Fe-based amorphous alloy strips laser-machined at a spot spacing of 0.05 mm were produced under the same conditions as in Comparative Example 102 described later, except that the line spacing was 60 mm. .. The number density D at this time is 0.33 pieces / mm ² .
In FIGS. 5 and 6, the Fe-based amorphous alloy strips laser-machined with a spot spacing of 0.10 mm were produced under the same conditions as in Example 101 described later, except that the line spacing was 60 mm. .. The number density D at this time is 0.167 pieces / mm ² .
In FIGS. 5 and 6, the Fe-based amorphous alloy strips laser-processed at a spot spacing of 0.20 mm were produced under the same conditions as in Example 103 described later (line spacing is 20 mm). The number density D at this time is 0.25 pieces / mm ² .
In FIGS. 5 and 6, the Fe-based amorphous alloy strip not laser-processed was produced under the same conditions as in Comparative Example 101 described later.

As shown in FIG. 5, it can be seen that the iron loss gradually increases as the magnetic flux density increases in the Fe-based amorphous alloy strip under any condition.
Further, it can be seen that the iron loss is reduced by performing laser processing on the Fe-based amorphous alloy strip under each condition of the spot spacing of 0.05 mm, the spot spacing of 0.10 mm, and the spot spacing of 0.20 mm. The effect itself of reducing iron loss by laser processing is as described in publicly known documents such as Japanese Patent Application Laid-Open No. 61-29103 and International Publication No. 2011/030907.

As shown in FIG. 6, it can be seen that under the condition of the magnetic flux density of 1.3 T, there is almost no difference in the exciting power between the four types of Fe-based amorphous alloy strips. That is, it can be seen that under the condition of the magnetic flux density of 1.3 T, the presence or absence of laser processing has almost no effect on the exciting power. Therefore, under the premise that iron loss and exciting power are measured at a magnetic flux density of 1.3 T, by performing laser processing on the Fe-based amorphous alloy strip, iron loss can be reduced with almost no increase in exciting power. The effect can be obtained.
However, paying attention to the Fe-based amorphous alloy strip having a spot spacing of 0.05 mm in FIG. 6, it can be seen that the exciting power sharply increases when the magnetic flux density exceeds 1.3 T. As a result, under the condition of the magnetic flux density of 1.45T, the Fe-based amorphous alloy strip having a spot spacing of 0.05 mm has a significantly higher excitation power than the other three types of Fe-based amorphous alloy strips. It turns out that it becomes.

As described above, the present inventors have significantly high excitation power under the condition of magnetic flux density of 1.45 T when the spot interval of the laser irradiation mark is too narrow, such as when the spot interval is 0.05 mm. It was found that there is a tendency to become (see FIG. 6). Further, the present inventors have increased the exciting power under the condition of the magnetic flux density of 1.45 T by widening the spot interval to 0.20 mm (that is, reducing the number density of the laser irradiation marks). It was also found that this can be suppressed (see FIG. 6).
Furthermore, the present inventors have also found that the effect of reducing iron loss by laser processing can be obtained even if the spot spacing is increased to 0.10 mm or 0.20 mm (see FIG. 5).
These findings are also shown in Table 9 of the Examples described below.
From this, by widening the spot interval and reducing the number density D, an increase in exciting power is suppressed under the condition of a magnetic flux density of 1.45 T, and a low-loss Fe-based amorphous alloy strip is obtained. It was found that it can be done.

Further, the present inventors may also increase the line spacing of the plurality of point-row laser irradiation marks (for example, by setting the line spacing to 10 mm or more), as in the case of widening the spot spacing. It was found that the increase in exciting power under the condition of a density of 1.45 T can be suppressed, and the effect of reducing iron loss by laser processing can be obtained.
This finding is shown in Table 10 of the Examples described below.

By the way, for example, as described in the above-mentioned International Publication No. 2012/102379, iron loss has been reduced by forming wavy irregularities on the free-solidified surface of the Fe-based amorphous alloy strip. Was there. The wavy unevenness is also called a chatter mark or the like, and is generated due to the vibration of the paddle when manufacturing (casting) an Fe-based amorphous alloy strip (for example, International Publication No. 2012/102379). See paragraph 0008). In the technique of forming wavy irregularities to reduce iron loss, the wavy irregularities are intentionally formed on the free solidified surface by adjusting the production conditions of the Fe-based amorphous alloy strip.

In contrast to the technique of forming wavy irregularities to reduce iron loss, the conventional laser machining techniques described in, for example, Japanese Patent Application Laid-Open No. 61-29103 and International Publication No. 2011/030907 have wavy irregularities on the free solidified surface. This is a technique for obtaining an effect similar to that of wavy irregularities (effect of reducing iron loss, etc.) by performing laser processing on a free solidified surface instead of forming the surface. Therefore, in the conventional laser processing technique, in order to form a shape similar to wavy unevenness, the line spacing is narrowed (for example, Japanese Patent Application Laid-Open No. 61-29103 and International Publication No. 2011/030907). As described in the example, the line spacing was set to 5 mm), that is, the number density of the laser irradiation marks was relatively high to form the laser irradiation marks.
Conventionally, since the exciting power is measured under the condition of the magnetic flux density of 1.3 T, the demerit of increasing the number density of the laser irradiation marks (that is, the increase in the exciting power) has not been recognized. However, as described above, the present inventors have found that when the number density of the laser irradiation marks is increased, the exciting power measured under the condition of the magnetic flux density of 1.45T increases, and the laser irradiation marks It has been found that by reducing the number density, an increase in the exciting power measured under the condition of a magnetic flux density of 1.45 T can be suppressed.
The Fe-based amorphous alloy strip of the present disclosure is made by this finding.
Therefore, the Fe-based amorphous alloy strip of the present disclosure is common to the techniques described in JP-A-61-29103 and International Publication No. 2011/030907 in that laser irradiation marks are formed on the surface of the strip. However, the Fe-based amorphous alloy strip of the present disclosure is a technique for suppressing an increase in exciting power measured under the condition of a magnetic flux density of 1.45 T by reducing the number density of laser irradiation marks. Therefore, the technique is completely different from that described in JP-A-61-29103 and International Publication No. 2011/030907.

Hereinafter, the Fe-based amorphous alloy strip and its preferred embodiment of the present disclosure will be described in more detail.

The Fe-based amorphous alloy strip of the present disclosure is a Fe-based amorphous alloy strip having a free-solidifying surface and a roll surface.
The Fe-based amorphous alloy strip having a free-solidifying surface and a roll surface is a strip manufactured (cast) by the single roll method. The surface that is rapidly cooled and solidified in contact with the cooling roll during casting is the roll surface, and the surface opposite to the roll surface (that is, the surface that is exposed to the atmosphere during casting) is the free solidification surface. For the single roll method, publicly known documents such as International Publication No. 2012/102379 can be referred to as appropriate.

The Fe-based amorphous alloy strip of the present disclosure may be a strip that has not been cut after casting (for example, a roll body wound into a roll after casting), or is desired after casting. It may be a thin strip cut out to a size.

<Laser irradiation marks, dotted laser irradiation marks>
The Fe-based amorphous alloy strip of the present disclosure has a plurality of point-series laser irradiation marks composed of a plurality of laser irradiation marks on at least one surface.

Each of the plurality of laser irradiation marks constituting the point-series laser irradiation marks need only be a mark to which energy is applied by laser processing (that is, laser irradiation), and the shape of the laser irradiation marks (plan view shape and There is no particular limitation on the cross-sectional shape).
As long as each of the plurality of laser irradiation traces is a trace to which energy is applied by laser irradiation, the effect of reducing iron loss by laser irradiation can be obtained.

The plan view shape of the laser irradiation mark may be any plan view shape such as a crown shape, a donut shape, or a flat shape.
From the viewpoint of weather resistance (rust prevention) of laser irradiation marks in Fe-based amorphous alloy thin bands and improvement of space factor of Fe-based amorphous alloy thin bands, the plan view shape of laser irradiation marks is donut-shaped or flat. Is preferable, and a flat shape is more preferable. In the flat shape, when the iron core is formed by laminating thin bands, the space between the thin bands can be suppressed and the thin band density of the iron core can be improved.

In the Fe-based amorphous alloy strip of the present disclosure, among a plurality of dotted laser irradiation marks provided in the casting direction of the Fe-based amorphous alloy strip, Fe-based amorphous between the dotted laser irradiation marks adjacent to each other. When the center line spacing in the central portion in the width direction orthogonal to the casting direction of the alloy thin band is defined as the line spacing, the line spacing is preferably 10 mm to 60 mm.
The width direction is a direction orthogonal to the casting direction of the Fe-based amorphous alloy strip.
Further, when the point-series laser irradiation marks are formed on both sides of the free solidification surface and the roll surface of the thin band, the line spacing is the point-series laser irradiation marks on both sides when the thin band is viewed transparently. The subject is measured. For example, when the point-series laser irradiation marks are alternately formed on both sides in the casting direction of the thin band, the "point-series laser irradiation marks adjacent to each other" are the point sequences formed on one surface. The target is the laser irradiation mark and the point-row laser irradiation mark formed on the other surface and adjacent to the casting direction.
When the line spacing is 10 mm or more, it is possible to suppress an increase in the exciting power measured under the condition of the magnetic flux density of 1.45 T, as compared with the case where the line spacing is less than 10 mm.
When the line spacing is 60 mm or less, the effect of reducing the iron loss measured under the condition of the magnetic flux density of 1.45 T is excellent as compared with the case where the line spacing is more than 60 mm.
The line spacing is more preferably 10 mm to 50 mm, more preferably 10 mm to 40 mm, and even more preferably 10 mm to 30 mm.

The directions of the plurality of point-row laser irradiation marks are preferably substantially parallel, but are not limited to being substantially parallel. In the central portion in the width direction of the thin band, the line spacing is preferably 10 mm to 60 mm. The directions of the plurality of point-row laser irradiation marks may or may not be parallel.

The "central portion in the width direction" of the Fe-based amorphous alloy strip can be a portion having a certain width from the center in the width direction toward both ends in the width direction. For example, from the center in the width direction to both ends in the width direction, the range of the region where the "some width" is 1/4 of the entire width can be set as the central portion. Above all, it is more preferable to set the range of the region where the "certain width" is 1/2 of the entire width as the central portion.

As one embodiment of the present disclosure, the Fe-based amorphous alloy strips are parallel to each other with respect to the width direction in which each direction of the plurality of point-row laser irradiation marks is orthogonal to the casting direction of the Fe-based amorphous alloy strips. It may have an arrangement relationship that is not.
That is, even if the angle formed by each direction of the plurality of point-row laser irradiation marks and the width direction of the Fe-based amorphous alloy strip is 10 ° or more and intersects with the casting direction at an acute angle or an obtuse angle. Good.

In another embodiment of the present disclosure, the Fe-based amorphous alloy strip is oriented such that the directions of the plurality of point-row laser irradiation marks are orthogonal to the casting direction and the thickness direction of the Fe-based amorphous alloy strip. On the other hand, it is preferable that they are substantially parallel.
The fact that each direction of the plurality of point-series laser irradiation marks is substantially parallel to the direction orthogonal to the casting direction and the thickness direction of the Fe-based amorphous alloy strip means that each of the plurality of point-series laser irradiation marks. It means that the angle formed by the direction of the above and the direction orthogonal to the casting direction and the thickness direction of the Fe-based amorphous alloy strip is 10 ° or less.
However, the plurality of point-row laser irradiation marks are not limited to being substantially parallel.

Further, in the Fe-based amorphous alloy strip of the present disclosure, as one embodiment, the direction of each of the plurality of dotted laser irradiation marks is substantially parallel to the width direction of the Fe-based amorphous alloy strip. Is preferable.
The fact that each direction of the plurality of point-series laser irradiation marks is substantially parallel to the width direction of the Fe-based amorphous alloy thin band means that each direction of the plurality of point-series laser irradiation marks and the Fe-based amorphous alloy thin band It means that the angle formed by the width direction of the band is 10 ° or less.
However, the plurality of point-row laser irradiation marks are not limited to being substantially parallel.

As described above, the direction of the point-series laser irradiation marks does not have to be parallel to the direction orthogonal to the casting direction of the Fe-based amorphous alloy thin band, and the direction of the point-series laser irradiation marks and the Fe-based amorphous alloy thin band The angle formed by the casting direction may have an inclination angle of more than 10 °. In this way, even if the inclination angle is more than 10 °, it is interpreted that the point-row laser irradiation marks are provided along the direction orthogonal to the casting direction of the Fe-based amorphous alloy strip. The inclination angle is preferably less than 45 °, more preferably 40 ° or less, further preferably 30 ° or less, and further preferably 20 ° or less. Most preferably, it is 10 ° or less.

The Fe-based amorphous alloy strip of the present disclosure may have one laser irradiation trace row in the width direction of the strip, in which point-row laser irradiation marks are provided at regular intervals in the casting direction of the strip. , Two or more in the width direction of the thin band may be provided.

Specifically, the Fe-based amorphous alloy strip of the present disclosure provides a plurality of point-row laser irradiation marks provided in the casting direction of the Fe-based amorphous alloy strip in the width direction orthogonal to the casting direction.
(1) A mode having one row in the "central portion in the width direction" (hereinafter referred to as a single row group) may be used, or (2) a mode having a plurality of rows in the "central portion in the width direction" (hereinafter referred to as a plurality of row groups). It may be.)
Hereinafter, a plurality of point-row laser irradiation marks provided in the casting direction of the Fe-based amorphous alloy strip are also referred to as "group of irradiation mark rows".
In the latter multi-row group, there are a plurality of groups of irradiation scars in the width direction of the thin band, and it is not necessary for the positions of the point-row laser irradiation marks to be on the same line in the width direction among the multiple groups. , Each of the point-row laser irradiation marks may have a positional relationship shifted in the casting direction. For example, when there are two groups of irradiation scars in the width direction of the thin band, the two groups are separated by an irradiation scar non-formation region in the central part in the width direction of the thin band, and a plurality of groups arranged in one group. The point-series laser irradiation marks and the plurality of point-series laser irradiation marks arranged in the other group may be in a positional relationship in which they are alternately present with each other at a certain distance in the casting direction.

The line interval in the present disclosure is a value obtained as follows.
As in (1) above, when a plurality of point-row laser irradiation marks provided in the casting direction are provided as a single-row group having one row in the "central portion in the width direction", the line spacing is within the single-row group. In, the distance between two dotted laser irradiation marks adjacent to each other in the casting direction can be arbitrarily selected and measured at five points, and the average value of the measured values can be obtained. In this case, the plurality of point-row laser irradiation marks forming the single-row group are preferably present at regular intervals, but may be present at arbitrary intervals.
Further, as in (2) above, when a plurality of point-row laser irradiation marks provided in the casting direction are provided as a plurality of rows in the "central portion in the width direction" as a group of a plurality of rows, the line spacing is set. The value (average value) obtained in the same manner as in the above method for each "group of irradiation scars" in the plurality of rows can be further averaged. In this case, the plurality of point-row laser irradiation marks constituting each "group of irradiation marks" are preferably present at regular intervals, but may be present at arbitrary intervals.

In the Fe-based amorphous alloy strip of the present disclosure, when the center point spacing of the individual laser irradiation marks constituting the plurality of point-row laser irradiation marks is the spot spacing, the spot spacing is 0.10 mm to 0.50 mm. .. Therefore, configurations formed continuously with a spot spacing of less than 0.10 mm are not included.
When the spot spacing is 0.10 mm or more, it is possible to suppress an increase in the exciting power measured under the condition of the magnetic flux density of 1.45 T as compared with the case where the spot spacing is less than 0.10 mm (FIG. 6 described above). reference).
When the spot spacing is 0.50 mm or less, the effect of reducing the iron loss measured under the condition of the magnetic flux density of 1.45 T is excellent as compared with the case where the spot spacing is more than 0.50 mm.
The spot spacing is preferably 0.15 mm to 0.40 mm, more preferably 0.20 mm to 0.40 mm.

As described above, the Fe-based amorphous alloy strip of the present disclosure is measured under the condition of a magnetic flux density of 1.45 T by making the number density of the laser irradiation marks constituting the dotted laser irradiation marks smaller than before. This is an attempt to suppress an increase in exciting power.

Further, in the Fe-based amorphous alloy strip of the present disclosure, when the line spacing is d1 (mm) and the spot spacing is d2 (mm), the number density D of the laser irradiation marks is set to the value calculated by the following formula. ..
D = (1 / d1) × (1 / d2)
The number density D is a value calculated from the line interval and the spot interval, and represents the density of the formed laser irradiation marks. ^{That is, in a unit area (mm 2} ) having a certain line spacing and spot spacing, the number density (D) satisfying d1 × d2 × D = 1 is 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ² . is there.
By setting the number density D of the laser irradiation marks to an appropriate value (a value smaller than the conventional value), it is possible to suppress an increase in the exciting power measured under the condition of a magnetic flux density of 1.45 T.

The number density D of the laser irradiation marks constituting the dotted laser irradiation marks is 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ² .
The number density D of the laser irradiation marks constituting the dotted laser irradiation marks is more preferably 0.10 pieces / mm ^{2 to} 0.50 pieces / mm ² .

When there are a plurality of point-row laser irradiation marks in the present disclosure, the number density D can be obtained as follows depending on the case.
As in (1) above, when a plurality of point-row laser irradiation marks provided in the casting direction are provided as a single-row group having one row in the "central portion in the width direction", the number density D is a single-row group. Arbitrarily select 5 "point-row laser irradiation marks adjacent to each other" from a plurality of point-series laser irradiation marks constituting the above, measure each line interval and spot interval, and obtain the average value of each measured value. , The number density D is obtained from the above formula from the average value of the line spacing and the average value of the spot spacing. The effect of the present invention is exhibited when the obtained number density D is in ^{the range of 0.05 pieces / mm 2 to} 0.50 pieces / mm ^2.
Further, as in (2) above, when a plurality of point-row laser irradiation marks provided in the casting direction are provided as a group of a plurality of rows in the "central portion in the width direction", the number density D is , Each "group of irradiation scars" in the group of multiple rows is obtained by the same method as above. Then, among the obtained number density D, the number density D in at least one "irradiation scar row group" in the plurality of row groups is in the range of ^{0.05 pieces / mm 2 to} 0.50 pieces / mm ^2. It is preferable that the average value of the obtained number density D is in the range of 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ² in that the effect is exhibited and the effect of the present invention is more exhibited. It is more preferable that the number density D in all the “groups of irradiation scars” in the plurality of rows ^{is in the range of 0.05 / mm 2 to} 0.50 / mm ^2.

Here, the "casting direction" is a direction corresponding to the circumferential direction of the cooling roll when casting the Fe-based amorphous alloy strip, in other words, the Fe-based amorphous alloy strip after casting and before being cut. It is the direction corresponding to the longitudinal direction of.
Even in the cut out thin strip piece, it is possible to confirm which direction the "casting direction" is by observing the free solidification surface and / or the roll surface of the thin strip piece. For example, thin streaks along the casting direction are observed on the free solidification surface and / or the roll surface of the thin strip piece. Further, the direction orthogonal to the casting direction is the width direction.

Further, the ratio of the length in the width direction of the dotted laser irradiation marks to the entire length in the width direction of the Fe-based amorphous alloy strip is 10% to 10% in the direction from the center in the width direction to both ends in the width direction. It is preferably 50%. In addition, "%" here is 100% of the entire length in the width direction of the Fe-based amorphous alloy strip.
When the direction of the point-series laser irradiation marks has an inclination with respect to the width direction, the point-series laser irradiation marks are formed instead of the length of the inclined point-series laser irradiation marks themselves. The value converted into the length in the width direction of the thin band in the portion is defined as the length of the point-series laser irradiation mark.

The above-mentioned length ratio of 50% means that the point-row laser irradiation marks start from the center in the width direction of the Fe-based amorphous alloy strip and reach one end and the other end in the width direction. Means. This "starting from the center and reaching one end and the other end in the width direction" means that at one end and the other end, the laser irradiation mark at the end of the point-row laser irradiation mark and the end of the Fe-based amorphous alloy strip. It means that the distance from the portion is equal to or less than the spot distance of the laser irradiation mark.
For example, when the direction of the dotted laser irradiation marks and the width direction of the Fe-based amorphous alloy strip are parallel, the entire length of the Fe-based amorphous alloy strips in the direction of the dotted laser irradiation marks is Fe-based. Corresponds to the full width of amorphous alloy strips.
Further, the above-mentioned length ratio of 10% means that each has a length of 10% from the center in the width direction toward both ends in the width direction, that is, the width length is defined as the central region in the entire width. It means that it has a dotted laser irradiation mark with a length of 20%. In other words, it means that the dotted laser irradiation marks are formed at both ends of the Fe-based amorphous alloy strip in the width direction, leaving a margin of 40% with respect to the total length in the width direction. ..
The ratio of the length of the point-row laser irradiation mark of the Fe-based amorphous alloy thin band to the entire length in the width direction in the width direction is from the center in the width direction to both ends in the width direction. It is more preferable that each of them is 25% or more.

Further, the point-row laser irradiation marks are formed in the six regions in the center of the width direction, excluding the two regions at both ends from the eight regions obtained by dividing the width direction of the Fe-based amorphous alloy strip into eight equal parts. It is preferably formed at least.

<Roughness of free solidified surface (maximum cross-sectional height Rt)>
By the way, for example, as described in the above-mentioned International Publication No. 2012/102379, conventionally, iron loss has been reduced by providing wavy irregularities on the free solidifying surface.
However, according to the study by the present inventors, it has been found that the wavy unevenness may cause an increase in the exciting power measured under the condition of the magnetic flux density of 1.45 T.
Therefore, from the viewpoint of suppressing the increase in the exciting power measured under the condition of the magnetic flux density of 1.45 T, it is preferable that the wavy unevenness is reduced as much as possible.
Specifically, the maximum cross-sectional height Rt in the portion other than the plurality of point-row laser irradiation marks on the free solidification surface is preferably 3.0 μm or less. When the maximum cross-sectional height Rt is 3.0 μm or less, it means that there is no wavy unevenness on the free solidified surface or the wavy unevenness is reduced.

In the present specification, the maximum cross-sectional height Rt in the portion other than the plurality of point-row laser irradiation marks on the free solidification surface is JIS B 0601: for the portion other than the plurality of point-row laser irradiation marks on the free solidification surface. According to 2001, the evaluation length is 4.0 mm, the cutoff value is 0.8 mm, and the cutoff type is 2RC (phase compensation) for measurement (evaluation). Here, the direction of the evaluation length is the casting direction of the Fe-based amorphous alloy strip. Further, the above measurement in which the evaluation length is 4.0 mm is specifically performed by continuously measuring 5 times with a cutoff value of 0.8 mm.
The maximum cross-sectional height Rt in the portion other than the plurality of point-row laser irradiation marks on the free solidifying surface is more preferably 2.5 μm or less.
The lower limit of the maximum cross-sectional height Rt is not particularly limited, but from the viewpoint of manufacturing suitability of the Fe-based amorphous alloy strip, the lower limit of the maximum cross-sectional height Rt is preferably 0.8 μm, more preferably 0.8 μm. It is 1.0 μm.

<Chemical composition>
The chemical composition of the Fe-based amorphous alloy strip of the present disclosure is not particularly limited, and may be any chemical composition of the Fe-based amorphous alloy (that is, a chemical composition containing Fe (iron) as a main component). However, from the viewpoint of more effectively obtaining the effect of the Fe-based amorphous alloy strip of the present disclosure, the chemical composition of the Fe-based amorphous alloy strip of the present disclosure is preferably the following chemical composition A.
The chemical composition A, which is a preferable chemical composition, is composed of Fe, Si, B, and impurities, and when the total content of Fe, Si, and B is 100 atomic%, the Fe content is 78 atomic% or more. It is a chemical composition in which the content of B is 10 atomic% or more and the total content of B and Si is 17 atomic% to 22 atomic%.
Hereinafter, the chemical composition A will be described in more detail.

In the chemical composition A, the Fe content is 78 atomic% or more.
Fe (iron) is one of the transition metals having the largest magnetic moment even if it has an amorphous structure, and is a carrier of magnetism in Fe—Si—B-based amorphous alloys.
When the Fe content is 78 atomic% or more, the saturation magnetic flux density (Bs) of the Fe-based amorphous alloy strip can be increased (for example, Bs of about 1.6 T can be realized). Further, it becomes easy to achieve a preferable magnetic flux density B0.08 (1.52T or more) described later.
The Fe content is preferably 80 atomic% or more, more preferably 80.5 atomic% or more, still more preferably 81.0 atomic% or more. Further, it is preferably 82.5 atomic% or less, and more preferably 82.0 atomic% or less.

In the chemical composition A, the content of B is 10 atomic% or more.
B (boron) is an element that contributes to amorphous formation. When the content of B is 10 atomic% or more, the amorphous forming ability is further improved.
Further, when the B content is 10 atomic% or more, the magnetic domain is likely to be oriented in the casting direction, and the magnetic flux density (B0.08) is likely to be improved by widening the magnetic domain width.
The content of B is preferably 11 atomic% or more, more preferably 12 atomic% or more, still more preferably 13 atomic% or more.
The upper limit of the content of B depends on the total content of B and Si described later, but is preferably 16 atomic%.

In the chemical composition A, the total content of B and Si is 17 atomic% to 22 atomic%.
Si (silicon) is an element that segregates on the surface in the molten metal state and has the effect of preventing oxidation of the molten metal. Further, Si acts as an auxiliary agent for forming an amorphous substance, has an effect of raising the glass transition temperature, and is also an element for forming a more thermally stable amorphous phase.
When the total content of B and Si is 17 atomic% or more, the above-mentioned effect of Si is effectively exhibited.
Further, when the total content of B and Si is 22 atomic% or less, a large amount of Fe, which is a bearer of magnetism, can be secured, so that the saturation magnetic flux density Bs is improved and the magnetic flux density B0.08 is improved. Is advantageous.
The Si content is preferably 2.0 atomic% or more, more preferably 2.4 atomic% or more, and further preferably 3.5 atomic% or more.
The upper limit of the Si content depends on the total content of B and Si, but is preferably 6.0 atomic%.

Among the above chemical compositions A, from the viewpoint of further improving iron loss and exciting power, which will be described later, a more preferable chemical composition of the Fe-based amorphous alloy strip is composed of Fe, Si, B, and impurities, and Fe, Si, When the total content of and B is 100 atomic% or more, the content of Fe is 80 atomic% or more, the content of B is 12 atomic% or more, and the total content of B and Si is 17 atomic% or more. ~ 20 atomic%.

The chemical composition A contains impurities.
In this case, the impurities contained in the chemical composition A may be only one type or two or more types.
Impurities include all elements other than Fe, Si, and B. Specifically, for example, C, Ni, Co, Mn, O, S, P, Al, Ge, Ga, Be, Ti, Examples thereof include Zr, Hf, V, Nb, Ta, Cr, Mo, and rare earth elements.
These elements can be contained in a range of 1.5% by mass or less in total with respect to the total mass of Fe, Si, and B. The total content of these elements is preferably 1.0% by mass or less, more preferably 0.8% by mass or less, still more preferably 0.75% by mass or less. In this range, these elements may be added.

<Thickness>
The thickness of the Fe-based amorphous alloy strip of the present disclosure is not particularly limited, but the thickness is preferably 18 μm to 35 μm.
A thickness of 18 μm or more is advantageous in terms of suppressing waviness of the Fe-based amorphous alloy strip and improving the space factor.
A thickness of 35 μm or less is advantageous in terms of suppressing embrittlement of the Fe-based amorphous alloy strip and magnetic saturation.
The thickness of the Fe-based amorphous alloy strip is more preferably 20 μm to 30 μm.

<Iron loss>
As described above, in the Fe-based amorphous alloy strip of the present disclosure, iron loss is reduced under the conditions of a frequency of 60 Hz and a magnetic flux density of 1.45 T by subdividing the magnetic domain by laser processing (formation of laser irradiation marks).
The iron loss under the conditions of a frequency of 60 Hz and a magnetic flux density of 1.45 T is 0.150 W / kg or less, preferably 0.140 W / kg or less, and more preferably 0.130 W / kg or less.
The lower limit of iron loss under the conditions of a frequency of 60 Hz and a magnetic flux density of 1.45 T is not particularly limited, but from the viewpoint of manufacturing suitability of an Fe-based amorphous alloy strip, the lower limit of iron loss is preferably 0.050 W / kg. is there.
Further, in the Fe-based amorphous alloy strip of the present disclosure, iron loss CL under the conditions of a frequency of 50 Hz and a magnetic flux density of 1.45 T is also reduced. In the Fe-based amorphous alloy strip of the present disclosure, the iron loss CL is preferably 0.120 W / kg or less under the conditions of a frequency of 50 Hz and a magnetic flux density of 1.45 T.
Further, in the Fe-based amorphous alloy strip of the present disclosure, iron loss at a frequency of 50 Hz and a magnetic flux density of 1.3 T, or iron loss at a frequency of 60 Hz and a magnetic flux density of 1.3 T is also reduced. It is preferable that the iron loss at a frequency of 50 Hz and a magnetic flux density of 1.3 T is 0.08 W / kg or less, or the iron loss at a frequency of 60 Hz and a magnetic flux density of 1.3 T is 0.11 W / kg or less.

The measurement of iron loss in the Fe-based amorphous alloy strip is measured according to JIS C2535: 2017 or JIS H7152: 1996.

<Excitation power>
As described above, in the Fe-based amorphous alloy strip of the present disclosure, an increase in exciting power under the condition of a magnetic flux density of 1.45 T is suppressed.
The exciting power under the conditions of a frequency of 60 Hz and a magnetic flux density of 1.45 T is preferably 0.200 VA / kg or less, more preferably 0.170 VA / kg or less, and further preferably 0.165 VA / kg or less.
The lower limit of the exciting power under the conditions of a frequency of 60 Hz and a magnetic flux density of 1.45 T is not particularly limited, but from the viewpoint of manufacturing suitability of the Fe-based amorphous alloy strip, the lower limit of the exciting power is preferably 0.100 VA / kg. is there.

<Magnetic flux density B0.08>
As described above, in the Fe-based amorphous alloy strip of the present disclosure, the increase in the exciting power under the condition of the magnetic flux density of 1.45 T is suppressed, so that the decrease in the magnetic flux density B0.08 due to the increase in the exciting power is suppressed. As a result, the magnetic flux density B0.08 can be maintained high.
In the Fe-based amorphous alloy strip of the present disclosure, the magnetic flux density B0.08 under the conditions of a frequency of 60 Hz and a magnetic field of 8 A / m is preferably 1.52 T or more.
The upper limit of the magnetic flux density B0.08 under the conditions of a frequency of 60 Hz and a magnetic field of 8 A / m is not particularly limited, but the upper limit is preferably 1.62 T.

<Ratio [Operating magnetic flux density Bm / Saturated magnetic flux density Bs]>
As described above, in the Fe-based amorphous alloy strip of the present disclosure, iron loss and exciting power under the condition of magnetic flux density of 1.45T, which is higher than the conventional condition of magnetic flux density of 1.3T, are suppressed to be low. Can be done.
Therefore, even when the ratio [operating magnetic flux density Bm / saturated magnetic flux density Bs] (hereinafter, also referred to as “Bm / Bs ratio”) is used at an operating magnetic flux density Bm under conditions higher than before, iron loss and excitation Power can be suppressed.

In this regard, the Fe-based amorphous alloy strip according to the conventional example has a saturation magnetic flux density Bs of 1.56T and an operating magnetic flux density Bm of 1.35T (that is, Bm / Bs ratio = 0. It was used in 87) (see, for example, IEEE TRANSACTIONS ON MAGNETICS Vol: 44, Issue: 11, Nov.2008, pp.4104-4106 (particularly, p.4106)).
On the other hand, in the Fe-based amorphous alloy strip of the present disclosure, for example, the Bs of the Fe-based amorphous alloy strip having _{the chemical composition (Fe 82} Si ₄ B _{14) of the examples described later is 1.63 T.} Bs is almost uniquely determined by the chemical composition. In this case, the Fe-based amorphous alloy strip of the present disclosure can be used at a Bm of 1.43 T or more (preferably 1.45 T to 1.50 T). The Bm / Bs ratio when Bm is 1.43T is 0.88, and the Bm / Bs ratio when Bm is 1.50T is 0.92.

For the above reasons, the Fe-based amorphous alloy strip of the present disclosure has an operating magnetic flux density of Bm satisfying that the Bm / Bs ratio is 0.88 to 0.94 (preferably 0.89 to 0.92). It is particularly suitable for applications used in
The Fe-based amorphous alloy strip of the present disclosure is used at an operating magnetic flux density Bm satisfying that the Bm / Bs ratio is 0.88 to 0.94 (preferably 0.89 to 0.92). However, iron loss and an increase in exciting power can be suppressed.

-Manufacturing method of Fe-based amorphous alloy strip (Manufacturing method X)-
The Fe-based amorphous alloy strip of the present disclosure described above can be preferably produced by the following production method X.
Manufacturing method X is
A process of preparing a material strip which is made of an Fe-based amorphous alloy and has a free-solidifying surface and a roll surface (hereinafter, also referred to as "material preparation process")
Multiple point-series laser irradiation by forming a plurality of point-series laser irradiation marks composed of a plurality of laser irradiation marks by laser processing on at least one of the free-solidifying surface and the roll surface of the material thin band. The process of obtaining a Fe-based amorphous alloy strip with marks (hereinafter, also referred to as "laser processing process"),
Have,
Of the plurality of point-row laser irradiation marks provided in the casting direction of the Fe-based amorphous alloy strip, the center line in the central portion in the width direction orthogonal to the casting direction between the point-series laser irradiation marks adjacent to each other. When the interval is the line interval and the center point interval of the plurality of laser irradiation marks in each of the plurality of point array laser irradiation marks is the spot interval, the spot interval is 0.10 mm to 0.50 mm, and the line interval is set. When d1 (mm), the spot interval is d2 (mm), and the number density D of the laser irradiation marks is D = (1 / d1) × (1 / d2), the number density D of the laser irradiation marks is 0. It is 0.05 pieces / mm ^{2 to} 0.50 pieces / mm ² .
The manufacturing method X may have other steps other than the material preparation step and the laser processing step, if necessary.

-Material preparation process-
The material preparation step in the manufacturing method X is a step of preparing a material strip having a free solidifying surface and a roll surface.
The material strip referred to here may be a strip that has not been cut after casting (for example, a roll body that has been wound into a roll after casting), or has a desired size after casting. It may be a cut-out thin strip. The material strip is, so to speak, the Fe-based amorphous alloy strip of the present disclosure at the stage before the laser irradiation mark is formed.
The free-solidifying surface and the roll surface of the material strip are synonymous with the free-solidifying surface and the roll surface of the Fe-based amorphous alloy strip of the present disclosure, respectively.
The preferred embodiment of the material strip (eg, preferred chemical composition, preferred Rt) is similar to the preferred embodiment of the Fe-based amorphous alloy strip of the present disclosure, except for the presence or absence of laser irradiation marks.

The material preparation step may be a step of simply preparing a pre-cast (that is, already completed) material strip for use in the laser processing step, or a step of newly casting a material strip. It may be.
Further, the material preparation step may be a step of performing at least one of casting of the material thin band and cutting out the thin band piece from the material thin band.

-Laser processing process-
In the laser processing step in the manufacturing method X, a plurality of laser irradiation marks (specifically, a plurality of laser irradiation marks) are applied to at least one of the free solidification surface and the roll surface of the material thin band by laser processing (that is, by irradiating a laser). A point-series laser irradiation mark) composed of the laser irradiation marks of the above is formed.
Preferred embodiments of the laser irradiation marks and the dotted laser irradiation marks formed by the laser irradiation step (preferably, line spacing, spot spacing, number density of laser irradiation marks, etc.) are the Fe-based amorphous alloy strips of the present disclosure described above. This is the same as the preferred embodiment of the laser irradiation mark and the dotted laser irradiation mark in the above.

As described above, as long as each of the plurality of laser irradiation traces is a trace to which energy is applied by laser irradiation, the effect of reducing iron loss by laser irradiation can be obtained.
Therefore, the laser conditions in the laser processing step are not particularly limited, but the preferable conditions are as follows.
By controlling the irradiation energy of the laser beam with respect to the thickness of the Fe-based amorphous alloy strip, the diameter of the recess and the depth of the recess can be controlled.

In the laser processing step, the laser output (hereinafter, also referred to as “laser output”) for forming each laser irradiation mark is preferably 0.4 mJ to 2.5 mJ, and more preferably 0.6 mJ to 2. It is 5 mJ, more preferably 0.8 mJ to 2.5 mJ, further preferably 1.0 mJ to 2.0 mJ, and further preferably 1.3 mJ to 1.8 mJ.
The diameter of the laser beam (hereinafter, also referred to as “spot diameter”) is preferably 50 μm to 200 μm.
When the value obtained by dividing the laser output by the spot area is defined as the energy density of the laser, the energy density is preferably 0.01 J / mm ^{2 to} 1.50 J / mm ² , and more preferably 0.02 J / mm. It is mm ^{2 to} 1.30 J / mm ² , and more preferably 0.03 J / mm ^{2 to} 1.02 J / mm ² .

The pulse width of the laser is preferably 50 nsec or more, more preferably 100 nsec or more. By setting the pulse width in the above range, it is possible to efficiently improve the magnetic characteristics such as iron loss of the thin band piece forming the laser irradiation mark.
The pulse width refers to the time during which the laser is irradiated, and a small pulse width means that the irradiation time is short. That is, the total energy of the irradiation laser beam is represented by the product of the energy per unit time and the pulse width.

In the laser processing, when forming the concave portion, the pulsed laser beam is scanned in the thin band width direction and irradiated.
As the laser light source, a YAG laser, a CO ₂ gas laser, a fiber laser, or the like can be used. Of these, a fiber laser is preferable because it can stably irradiate a high-output, high-frequency pulsed laser beam for a long period of time. In a fiber laser, the laser beam introduced into the fiber oscillates on the principle of FBG (Fiber Bragg grating) by the diffraction gratings at both ends of the fiber. Since the laser beam is excited in the elongated fiber, there is no problem of the thermal lens effect in which the beam quality is deteriorated due to the temperature gradient generated inside the crystal. Further, since the fiber core is as thin as a few microns, the laser beam not only propagates in a single mode even at a high output, but also the beam diameter is narrowed to obtain a laser beam having a high energy density. Moreover, since the depth of focus is long, it is possible to accurately form a row of recesses even in a thin band having a width of 200 mm or more. The pulse width of the fiber laser is usually about microseconds to picoseconds.

The wavelength of the laser light is about 250 nm to 1100 nm depending on the laser light source, but a wavelength of 900 nm to 1100 nm is suitable because it is sufficiently absorbed in the alloy strip.
The beam diameter of the laser beam is preferably 10 μm or more, more preferably 30 μm or more, and more preferably 50 μm or more. The beam diameter is preferably 500 μm or less, more preferably 400 μm or less, and even more preferably 300 μm or less.

Further, the laser processing step may be a step of performing laser processing on the material thin band before winding after casting by the single roll method, or from the material thin band (roll body) after winding. It may be a step of performing laser processing on the unwound material thin band, or a laser on a thin band piece cut out from the material thin band unwound from the material thin band (roll body) after winding. It may be a process of performing processing.
When the laser machining step is a step of performing laser machining on the material strip before winding after casting by the single roll method, the manufacturing method X is performed, for example, between the cooling roll and the winding roll. This is carried out using a system in which a laser processing device is installed.

Hereinafter, examples of Fe-based amorphous alloy strips suitable for use in the transformers of the present disclosure will be shown.

[Example 101]
<Manufacturing of material strips (Fe-based amorphous alloy strips before laser processing)>
By the single roll method _{, a material strip having a chemical composition of Fe 82} Si ₄ B ₁₄ , a thickness of 25 μm, and a width of 210 mm (that is, a Fe-based amorphous alloy strip before laser machining) is formed. Manufactured. Here, the " _{chemical composition of Fe 82} Si ₄ B ₁₄ " is composed of Fe, Si, B, and impurities, and contains Fe when the total content of Fe, Si, and B is 100 atomic%. It means a chemical composition in which the amount is 82 atomic%, the B content is 14 atomic%, and the Si content is 4 atomic%.
The details of manufacturing the material strip will be described below.

In the production of the material strip, the _{molten metal having the chemical composition of Fe 82} Si ₄ B ₁₄ was maintained at a temperature of 1300 ° C., and then the molten metal was ejected from the slit nozzle onto the surface of the axially rotating cooling roll. The ejected molten metal was rapidly cooled and solidified on the surface of the cooling roll to obtain a material strip. At this time, the atmosphere on the surface of the cooling roll immediately below the slit nozzle on which the paddle of the molten metal is formed is a non-oxidizing gas atmosphere. The slit length of the slit nozzle was 210 mm, and the slit width was 0.6 mm. The material of the cooling roll was a Cu alloy, and the peripheral speed of the cooling roll was 27 m / s. The pressure at which the molten metal is ejected and the nozzle gap (that is, the gap between the tip of the slit nozzle and the surface of the cooling roll) are the maximum cross-sectional height Rt (specifically, casting of the material thin band) on the free solidification surface of the material thin band to be manufactured. The maximum cross-sectional height Rt) measured along the direction was adjusted to be 3.0 μm or less.

<Laser processing>
A sample piece was cut out from the material strip, and the cut sample piece was laser-processed to obtain a laser-processed Fe-based amorphous alloy strip.
The details will be described below.

FIG. 4 is a schematic plan view schematically showing the free solidification surface of the laser-processed Fe-based amorphous alloy strip piece (thin strip 10).
The length L1 of the thin band 10 shown in FIG. 4 (that is, the length of the sample piece cut out from the material thin band) is 120 mm, and the width W1 of the thin band 10 (that is, the width of the sample piece cut out from the material thin band) is 25 mm. And said. The sample piece was cut out in a direction in which the length direction of the sample piece and the length direction of the material strip coincide with each other, and the width direction of the sample piece and the width direction of the material strip coincide with each other.
By irradiating the free-solidified surface of the cut-out sample piece with a pulse laser, a plurality of point-row laser irradiation marks 12 composed of a plurality of laser irradiation marks 14 were formed, and a thin band 10 was obtained.
Specifically, a plurality of laser irradiation marks 14 are formed in a row in a direction parallel to the width direction of the sample piece on the free solidification surface of the sample piece (thin band 10 before laser processing; the same applies hereinafter). As a result, a dotted laser irradiation mark 12 was formed. The dotted laser irradiation marks 12 were formed over the entire width direction of the sample piece. That is, the length of the dotted laser irradiation marks in the width direction of the sample piece was set to 100% with respect to the total width of the sample piece. This is because the ratio of the length of the linear laser irradiation mark in the width direction to the total length of the Fe-based amorphous alloy strip in the width direction is 50% in the direction from the center in the width direction to both ends in the width direction. Corresponds to being.
A plurality of the above-mentioned point-row laser irradiation marks 12 were formed. The directions of the plurality of point-row laser irradiation marks 12 were made parallel.

Table 9 shows the spot interval SP1 (that is, the center point interval of the laser irradiation mark 14) and the line interval LP1 (that is, the center line interval of the point array laser irradiation mark 12) in the point sequence laser irradiation mark 12. As shown.
^{The number density (pieces / mm 2} ) of the laser irradiation marks in the thin band 10 was as shown in Table 9. The number density D (pieces / mm ² ) of the laser irradiation marks was calculated from the following formula.
D = (1 / d1) × (1 / d2)
In the formula, d1 represents the line spacing (unit: mm), and d2 represents the spot spacing (unit: mm).

The irradiation conditions of the pulse laser were as follows.
-Pulse laser irradiation conditions-
As the laser oscillator, a pulse fiber laser (YLP-HP-2-A30-50-100) manufactured by IPG Photonics was used. The laser medium of this laser oscillator is Yb-doped glass fiber, and the oscillation wavelength is 1064 nm. The diameter of the beam emitted from the collimator at the fiber end of the laser oscillator was 6.2 mm.
On the other hand, the spot diameter of the laser on the free solidifying surface of the sample piece was adjusted to be 60.8 μm. The beam diameter was adjusted using a beam expander (BE), which is an optical component, and a condenser lens (focal length 254 mm) having an fθ: f254 mm.
The beam mode M2 was set to 3.3 (multi-mode).
The output of the laser was 2.0 mJ, and the pulse width of the laser was 250 nsec.
The magnification of the beam by BE was set to 3 times, and Focus was set to 0 mm. Here, Focus means the difference (absolute value) between the focal length of the condenser lens (254 mm) and the actual distance from the condenser lens to the free solidification surface of the thin band.
Further, since the relationship of D0 = 4λf / πD (where λ represents the wavelength of the laser and f represents the focal length) holds between the incident diameter D and the spot diameter D0, the beam magnification BE (That is, as the incident diameter D increases), the spot diameter D0 tends to decrease.

Under the above irradiation conditions, when the value obtained by dividing the laser output (2.0 mJ) by the laser beam diameter (60.8 μm) on the free solidification surface of the sample piece is defined as the energy density, the energy density is J / mm. ^{Expressed in 2} units, it is 0.689 J / mm ² .

<Measurement and evaluation>
The laser-processed Fe-based amorphous alloy strip (thin strip 10 in FIG. 4) was measured and evaluated as follows. The results are shown in Table 9.

(Maximum cross-sectional height Rt of non-laser machined area)
In the free solidification surface of the laser-processed Fe-based amorphous alloy strip, the portion other than the point-row laser irradiation marks 12 (that is, the non-laser-processed region) is evaluated according to JISB 0601: 2001, and the evaluation length is 4. The maximum cross-sectional height Rt was measured with 0 mm, a cutoff value of 0.8 mm, and a cutoff type of 2RC (phase compensation). Here, the direction of the evaluation length was set to be the casting direction of the material thin band. The above-mentioned measurement having an evaluation length of 4.0 mm was carried out in detail by continuously measuring 5 times with a cutoff value of 0.8 mm. The above measurement with an evaluation length of 4.0 mm was performed at three locations in the non-laser machined region, and the average value of the three measured values obtained was taken as the maximum cross-sectional height Rt (μm) in this example. ..

(Measurement of iron loss CL)
For the laser-processed Fe-based amorphous alloy strip, the iron loss CL was measured by an AC magnetic measuring instrument under two conditions: a frequency of 60 Hz and a magnetic flux density of 1.45 T, and a condition of a frequency of 60 Hz and a magnetic flux density of 1.50 T. Was measured by sinusoidal excitation.

(Measurement of exciting power VA)
For the laser-processed Fe-based amorphous alloy strip, the exciting power VA is sine waved by an AC magnetic measuring instrument under the conditions of frequency 60 Hz and magnetic flux density 1.45 T, and frequency 60 Hz and magnetic flux density 1.50 T. Measured by excitation.

(Measurement of magnetic flux density B0.08)
The magnetic flux density B0.08 of the laser-processed Fe-based amorphous alloy strip was measured under the conditions of a frequency of 60 Hz and a magnetic field of 8 A / m.

[Comparative Example 101]
The same operation as in Example 101 was performed except that the laser processing was not performed. The results are shown in Tables 9 and 10.

[Examples 102 to 114, Comparative Examples 102 to 104]
The same operation as in Example 101 was performed except that the combination of the spot interval and the line interval was changed as shown in Tables 9 and 10.
In these examples, the maximum cross-sectional height Rt also has different values, but this maximum cross-sectional height Rt is not intentionally controlled. It is technically difficult to intentionally control the maximum cross-sectional height Rt in the range where the maximum cross-sectional height Rt is 3.0 μm or less. The results are shown in Tables 9 and 10.

[Comparative Example 105]
The same evaluation as in Comparative Example 101 was performed except that the pressure for ejecting the molten metal and the nozzle gap were adjusted so that the maximum cross-sectional height Rt was more than 3.0 μm. The results are shown in Table 10. In the Fe-based amorphous alloy strip of Comparative Example 105, wavy irregularities were formed on the free solidified surface.

As shown in Tables 9 and 10, the spot spacing (that is, the center point spacing of a plurality of laser irradiation marks) is 0.10 mm to 0.50 mm, and the number density D of the laser irradiation marks is 0.05. In the Fe-based amorphous alloy strips of Examples 101 to 114 having a magnetic flux density of 1.45 T, iron loss CL and exciting power VA were reduced in the Fe-based amorphous alloy strips of / mm ^{2 to} 0.50 / mm ^2. Further, the line spacing of Examples 101 to 114 (that is, the center line spacing of the plurality of point-row laser irradiation marks) was 10 mm to 60 mm.
On the other hand, the iron loss CL was high in the Fe-based amorphous alloy strip of Comparative Example 101 in which the laser irradiation marks were not formed.
Further, in the Fe-based amorphous alloy strip of Comparative Example 102 in which the spot interval was less than 0.10 mm, the iron loss CL was reduced, but the exciting power VA was high.
Further, in the Fe-based amorphous alloy strips of Comparative Examples 103 and 104 in which the line spacing was less than 10 mm, the iron loss CL was reduced, but the exciting power VA was high.
Further, in the Fe-based amorphous alloy strip of Comparative Example 105, which has no laser irradiation mark and the maximum cross-sectional height Rt in the non-laser machined region of the free solidified surface is more than 3.0 μm, the iron loss CL is reduced. However, the exciting power VA was high.

<Shape of laser irradiation mark>
The plan-view shape of the laser irradiation mark of the Fe-based amorphous alloy strip of Examples 101 to 114 was observed with an optical microscope. As a result, in all the examples, the plan view shape of the laser irradiation mark was crown-shaped. Here, the crown shape means a shape in which traces of scattered molten alloy remain at the edge portion of the laser irradiation trace.

By the way, the saturation magnetic flux density Bs in the Fe-based amorphous alloy strip having the chemical composition of _{Fe 82} Si ₄ B _{14 is 1.63 T.}
In Examples 101 to 114, the ratio [operating magnetic flux density Bm / saturated magnetic flux density Bs] of the iron loss CL and the exciting power VA under the condition of the magnetic flux density of 1.45T is 0.89 (= 1.45 / 1.63). This is an example assuming that an Fe-based amorphous alloy strip is used at an operating magnetic flux density Bm that satisfies the above. The iron loss CL and the exciting power VA under the condition of a magnetic flux density of 1.50 T are the ratio [operating magnetic flux]. This is an example assuming that an Fe-based amorphous alloy strip is used at an operating magnetic flux density Bm that satisfies that the density Bm / saturation magnetic flux density Bs] is 0.92 (= 1.50 / 1.63). ..
From the results of Tables 9 and 10, the Fe-based amorphous alloy strips of Examples 101 to 114 satisfy the operation that the ratio [operating magnetic flux density Bm / saturated magnetic flux density Bs] is 0.88 to 0.94. Even when used at a magnetic flux density of Bm, it is expected that iron loss and exciting power can be suppressed.

Claims (10)

On at least one surface of the Fe-based amorphous alloy strip, a plurality of point-row laser irradiation marks provided along a direction orthogonal to the casting direction of the Fe-based amorphous alloy strip are provided.
Among the plurality of point-row laser irradiation marks, the center line spacing in the central portion in the width direction orthogonal to the casting direction between the point-row laser irradiation marks adjacent to each other is defined as the line spacing, and the point-series laser irradiation When the distance between the center points of the individual laser irradiation marks constituting the marks is the spot spacing, the spot spacing is 0.10 mm to 0.50 mm, the line spacing is d1 (mm), and the spot spacing is defined as the spot spacing. When d2 (mm) and the number density D of the laser irradiation marks is D = (1 / d1) × (1 / d2), the number density D of the laser irradiation marks is 0.05 pieces / mm ² to 0.50 pieces / mm ²
The iron core formed by using the Fe-based amorphous alloy thin band having an iron loss of 0.150 W / kg or less at a frequency of 60 Hz and a magnetic flux density of 1.45 T in a single plate of the Fe-based amorphous alloy thin band, and the iron core. Transformer with wound windings. The transformer according to claim 1, wherein the transformer is a single-phase transformer, and the no-load loss per weight of the iron core is 0.15 W / kg or less at 50 Hz or 0.19 W / kg or less at 60 Hz. vessel. The transformer according to claim 1, wherein the transformer is a three-phase transformer, and the no-load loss per weight of the iron core is 0.19 W / kg or less at 50 Hz or 0.24 W / kg or less at 60 Hz. vessel. The transformer according to any one of claims 1 to 3, wherein the rated capacity of the transformer is 10 kVA or more. The transformer according to any one of claims 1 to 4, wherein the line spacing d1 is 10 mm to 60 mm. The ratio of the length of the point-row laser irradiation mark in the width direction to the total length of the Fe-based amorphous alloy strip in the width direction is 10% to 10% in the direction from the center in the width direction to both ends in the width direction. The transformer according to any one of claims 1 to 5, which is within the range of 50%. The transformer according to any one of claims 1 to 6, wherein the thickness of the Fe-based amorphous alloy strip is 18 μm to 35 μm. The Fe-based amorphous strip is composed of Fe, Si, B, and impurities, and the Fe content is 78 atomic% or more when the total content of Fe, Si, and B is 100 atomic%. The transformer according to any one of claims 1 to 7, wherein the content of B is 10 atomic% or more, and the total content of B and Si is 17 atomic% to 22 atomic%. The Fe-based amorphous alloy strip has a free solidifying surface and a roll surface, and the maximum cross-sectional height Rt on the free solidifying surface excluding the point-row laser irradiation scar portion is 3.0 μm or less. The transformer according to any one of claims 1 to 8. The dotted laser irradiation marks are located in the central 6 regions in the width direction, excluding the two regions at both ends from the eight regions obtained by dividing the width direction of the Fe-based amorphous alloy strip into eight equal parts. The transformer according to any one of claims 1 to 9, which is formed at least.

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