JP3744202B2 - Magnetic steel wire with excellent iron loss characteristics and workability - Google Patents

Description

【００２８】
【発明の効果】
以上説明したように、本発明によれば、伸線加工および鉄心加工性に優れるとともに、鉄損特性に優れた電磁鋼線を提供することができる。したがって、本発明は、変圧器やリアクトルなどの特に小型の鉄心用に適した新しい電磁鋼線を提供可能とする。
【図面の簡単な説明】
【図１】Ｃ＋Ｓ＋Ｏ＋Ｎの量とが鉄損に及ぼす影響を示す図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electromagnetic steel wire that is used in iron cores such as transformers and reactors and has excellent magnetic properties, particularly iron loss properties and workability.
[0002]
[Prior art]
Conventionally, directional or non-directional electrical steel sheets have been used as iron core materials such as transformers and reactors. Iron cores using these steel sheets are classified into a stacking type and a winding type depending on the lamination method, and both types require precise processing such as slitting, shearing or bending of the steel sheet.
For this reason, in particular, when the iron core is relatively small, there is a problem that machining itself becomes difficult, and the volume of the strained portion due to machining in the total volume of the iron core becomes relatively large. There was a problem of deteriorating magnetic properties.
[0003]
[Problems to be solved by the invention]
An electromagnetic steel wire is conceivable as an iron core material for dealing with such problems. By the way, looking back at the prior art from this point of view, although there is no target in the prior art for ultra-fine or small-diameter steel wires as the subject of the present invention, the aim was to improve the magnetic properties. There have been several proposals for wire rods.
For example, in Japanese Patent Application Laid-Open No. 59-215463 and Japanese Patent Application Laid-Open No. 4-285143, in order to improve magnetic properties and cold drawing workability, a low Si, low C component is used, and extremely low C is achieved. Each has been proposed. However, these methods have a problem that iron loss characteristics, particularly, iron loss in a high frequency region is increased.
Japanese Patent Laid-Open No. 60-181234 proposes to improve the texture by performing annealing after drawing in a decarburized atmosphere and at a temperature not lower than 750 ° C. and not higher than the A ₃ transformation point. Yes. However, this is also excellent in magnetic flux density characteristics, but the iron loss characteristics are not satisfactory. Japanese Patent Application Laid-Open No. 3-75311 is intended to improve wire drawing workability and magnetic properties by defining hot rolling conditions. However, the problem of high iron loss still remained.
Furthermore, in Japanese Patent Application Laid-Open No. 56-167302, a magnetic metal wire having an insulating film is proposed for an iron core of an induction heating furnace. However, iron loss deteriorates due to distortion during processing. There was a problem.
[0004]
Thus, in the prior art, all of them have mainly been developed mainly for large diameters, and these are drawn to a steel wire with a small diameter of 1.0 mm or less. When processed into an iron core, the texture deteriorates, so that magnetic property deterioration due to processing strain is large. Moreover, since the conventional materials were not aimed at development for transformers and reactors, the actual situation was that no investigation and consideration on iron loss characteristics were conducted.
Therefore, the present invention is to advantageously solve the above-mentioned problems of the prior art, and is excellent in workability such as wire drawing and iron core processing, and is less deteriorated in iron loss due to processing distortion, and high-frequency iron. An object of the present invention is to provide an electromagnetic steel wire having excellent loss characteristics.
Moreover, an object of this invention is to provide the novel electromagnetic steel wire suitable for iron cores, such as a transformer and a reactor, by satisfy | filling said each characteristic.
[0005]
[Means for Solving the Problems]
The inventors have conducted detailed studies on the steel composition in particular to achieve the above object. As a result, in order to obtain excellent iron loss, the specific impurity component in the steel wire must be reduced as much as possible in order to obtain excellent iron loss, as well as excellent wire drawing workability and small deterioration of iron loss due to processing distortion when processed into a transformer. In addition, it was found that adding an appropriate amount of Cr to the steel is extremely effective. This invention is completed based on such knowledge, The summary structure is as follows.
[0006]
(1) 0.1 to 10.0 wt% of Cr, C, S, O and N in the range of C + S + O + N <0.015 wt%, with the balance having a steel composition consisting of Fe and inevitable impurities, with a steel wire diameter of 0.01 to An electromagnetic steel wire with excellent iron loss and workability of 1.0 mm.
[0007]
(2) Cr is 0.1 to 10.0 wt%, Si is 0.2 to 8.0 wt%, C, S, O and N are contained in the range of C + S + O + N <0.015 wt%, and the balance has a steel composition consisting of Fe and inevitable impurities. And a steel wire diameter of 0.01 to 1.0 mm and excellent in iron loss characteristics and workability.
[0008]
(3) In the above (1) or (2), the steel composition is further
Mn: 2.0 wt% or less, Al: 2.0 wt% or less,
Cu: 2.0 wt% or less, Ni: 2.0 wt% or less,
P: An electromagnetic steel wire excellent in iron loss characteristics and workability with a composition containing one or more selected from 0.2 wt% or less.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Below, in the present invention, the reason why the component composition of steel is limited to the above range will be described including experimental facts.
Bloom: Si: 2.45wt%, Cr: 5.1wt%, Al: 0.3wt%, Mn: 0.5wt%, P: 0.02wt%, C + S + O + N amount 0.0050-0.0230wt% After making it a 5 mm wire, it was cold-drawn to 0.3 mm. This was annealed in a nitrogen atmosphere at 850 ° C. for 2 minutes. Using the obtained steel wire, a ring core having an average diameter of 10 cm was prepared, and 200 turns of primary and secondary windings were applied to perform magnetic measurement.
FIG. 1 shows the effect of C + S + O + N on iron loss W1 / 10000 (w / kg). As is apparent from FIG. 1, it is understood that the iron loss is remarkably reduced by adding Cr when the amount of C + S + O + N is 0.0150 wt% or less.
[0010]
As described above, the conventional material having a relatively large amount of C + S + O + N does not have the effect of reducing iron loss by adding Cr, whereas the invention material in which the amount of C + S + O + N is reduced to the limit exhibits the effect of reducing iron loss. The reason for this is not necessarily clear, but it is likely that these trace elements and Cr compounds have an effect on the texture formation through the effect on the sliding deformation behavior during wire drawing. This is thought to have led to a change in loss. In other words, despite the fact that Cr is known to reduce eddy current loss by increasing the specific resistance of steel, it does not always lead to a reduction in iron loss. Seems to be. In addition, the deformation behavior during wire drawing or the preferred texture formation mechanism is significantly different from that in rolling, so it is suitable in the component range that was never expected from the knowledge of conventional rolling. It is considered that the conditions existed.
[0011]
In addition, the steel wire diameter t in this invention shall be the range of 0.01-1.0 mm. This is because if it is less than 0.01 mm, wire drawing becomes difficult, and the workability of the actual transformer and reactor deteriorates, and if it exceeds 1.0 mm, the iron loss deterioration due to processing strain increases during actual machine processing. .
[0012]
Next, the component composition range of the electromagnetic steel wire in the present invention will be described.
C + S + O + N <0.015 wt%
C, S, O, and N are all elements that lower the ductility of steel and are components that impede cold drawing and processing into iron cores. It was found for the first time that when the total content C + S + O + N is 0.015 wt% or more, as shown in FIG. Therefore, the total amount of these components is less than 0.015 wt%.
[0013]
In addition, as for each component of C, S, O, and N, it is desirable to contain in the following ranges.
C: 0.010 wt% or less If C is contained in excess of 0.010 wt%, it dissolves in the steel and causes strain aging during processing to deteriorate ductility. Therefore, C is preferably 0.010 wt% or less.
[0014]
S: 0.010 wt% or less S forms sulfides and deteriorates ductility, and when finely dispersed, crystal grain growth and iron loss are reduced, so 0.010 wt% or less is recommended. desirable.
[0015]
O: 0.0050 wt% or less O is desirably 0.0050 wt% or less in order to form an oxide and reduce ductility and grain growth.
[0016]
N: 0.0050 wt% or less N, like C, causes strain aging during processing and deteriorates ductility. If N is large, nitrides are formed and texture formation is weakened. Therefore, N should be 0.0050 wt% or less. desirable.
[0017]
Cr: 0.1-10.0wt%
Cr has an effect of reducing eddy current loss due to an increase in specific resistance, and is particularly effective when Cr is added with C + S + O + N being less than 0.015 wt%. However, this effect is not exhibited when the Cr addition amount is less than 0.1 wt%. On the other hand, if the addition amount exceeds 10.0 wt%, the wire drawing workability deteriorates, so the addition is made in the range of 0.1 to 10.0 wt%.
[0018]
Moreover, it is desirable to add Si in the following content range.
Si: 0.2 to 8.0 wt%
Si is a useful component that increases the electrical resistance of steel wires and improves the iron loss characteristics. However, the addition of less than 0.2 wt% reduces the electrical resistance and increases eddy current loss. I can't get it. On the other hand, if it exceeds 8.0 wt%, cold rolling becomes difficult, so add in the range of 0.2 to 8.0 wt%.
[0019]
In addition to the above components, it is preferable to add at least one of Mn, Al, Cu, Ni and P in the following content range. However, the total amount of these components should be limited to 3.0 wt% or less.
Mn: 2.0 wt% or less
Mn is a useful component that increases the electrical resistance of the steel wire and improves the iron loss characteristics, but if it is 2.0 wt% or more, the texture deteriorates due to α / γ transformation during recrystallization annealing. In addition, a preferable content range is 0.1-1.5 wt%.
[0020]
Al: 2.0 wt% or less
Al is a useful component that increases the electrical resistance of the steel wire and improves the iron loss characteristics. However, if it exceeds 2.0 wt%, it promotes nitriding during annealing, thereby deteriorating the iron loss characteristics.
[0021]
Cu: 2.0 wt% or less
Cu is a useful component that increases the electrical resistance of the steel wire and improves the iron loss characteristics, but if it exceeds 2.0 wt%, the steel becomes brittle and cold working becomes difficult.
[0022]
Ni: 2.0 wt% or less
Ni is a useful component that increases the electrical resistance of the steel wire and improves the iron loss characteristics, but if it exceeds 2.0 wt%, the steel becomes brittle and cold workability deteriorates.
[0023]
P: 0.2 wt% or less P is a useful component that increases the electrical resistance of the steel wire and improves the iron loss characteristics. However, if it exceeds 2.0 wt%, the steel becomes brittle and cold working becomes difficult.
[0024]
It should be noted that the contents of Ti and Zr are preferably suppressed to 0,005 wt% or less in order to ensure crystal grain growth.
[0025]
The electromagnetic steel wire according to the present invention, after the molten steel adjusted to the above-mentioned preferred component composition is made into a bloom of a predetermined size by continuous casting or ingot-making / separation method, is hot-rolled wire by hot rolling once or Manufactured by performing at least two annealing processes including intermediate annealing and wire drawing (cold). The steel wire is then annealed or processed into an iron core, and then subjected to finish annealing for practical use. The electromagnetic steel wire may be coated with an insulating film in order to improve insulation.
[0026]
【Example】
Hereinafter, specific description will be given based on examples.
After melting steel consisting of the chemical components shown in Table 1 and the balance substantially Fe to form a bloom, a hot-rolled wire with a diameter of 5 mm was produced, and electromagnetic steel wires with various wire diameters were produced by a single wire drawing process. did. This electromagnetic steel wire was annealed in a nitrogen atmosphere at 900 ° C. for 2 minutes. Using this annealed steel wire, a ring core with an average diameter of 10 cm was fabricated, and 200 turns of primary and secondary windings were applied to perform magnetic measurements. Further, the workability was judged by whether or not it was broken even once during wire drawing. The obtained results are summarized in Table 1. As is clear from Table 1, the magnetic steel wire of the inventive example had better iron loss characteristics than the comparative example, and there was no problem in workability (drawing process, iron core process) at all. On the other hand, the comparative example had both poor iron loss characteristics and workability.
[0027]
[Table 1]

[0028]
【The invention's effect】
As described above, according to the present invention, it is possible to provide an electromagnetic steel wire that is excellent in wire drawing and iron core workability and excellent in iron loss characteristics. Therefore, the present invention can provide a new electromagnetic steel wire suitable for a particularly small iron core such as a transformer or a reactor.
[Brief description of the drawings]
FIG. 1 is a graph showing the influence of the amount of C + S + O + N on iron loss.

Claims (3)

  Cr contains 0.1 to 10.0 wt%, C, S, O and N in the range of C + S + O + N <0.015 wt%, the balance has a steel composition consisting of Fe and inevitable impurities, and the steel wire diameter is 0.01 to 1.0 mm. An electromagnetic steel wire with excellent iron loss characteristics and workability. 0.1 to 10.0 wt% of Cr, 0.2 to 8.0 wt% of Si, C, S, O and N are contained in the range of C + S + O + N <0.015 wt%, and the balance has a steel composition consisting of Fe and inevitable impurities, An electromagnetic steel wire having a wire diameter of 0.01 to 1.0 mm and excellent iron loss characteristics and workability. The steel composition according to claim 1 or 2, further comprising:
Mn: 2.0 wt% or less, Al: 2.0 wt% or less,
Cu: 2.0 wt% or less, Ni: 2.0 wt% or less,
P: An electromagnetic steel wire excellent in iron loss characteristics and workability with a composition containing one or more selected from 0.2 wt% or less.

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