JPWO2018061530A1 - Method of manufacturing Fe-Ni based alloy sheet and Fe-Ni based alloy sheet - Google Patents

Abstract

Disclosed is an Fe-Ni-based alloy sheet capable of providing isotropic mechanical characteristics even when the width is increased, and a method of manufacturing the same. % By mass Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less, the balance being Fe and impurities, A hot rolling material having a thickness of 2 mm or more is used as a material for cold rolling, and the first cold rolling with a rolling reduction of 85% or more is performed on the material for cold rolling, and the first cold rolling Then, recrystallization annealing is performed under the conditions of temperature 800 ° C. or more and holding time 0.1 to 1.2 minutes, and after the recrystallization annealing, final cold rolling with a rolling reduction of 40% or less is performed, and the thickness is A method of producing an Fe-Ni-based alloy thin plate characterized by using a Fe-Ni-based alloy thin plate of 0.25 mm or less and not performing heat treatment after final cold rolling, and an Fe-Ni-based alloy thin plate.

Description

  The present invention relates to, for example, an Fe-Ni-based alloy thin plate used for a lead frame, a metal mask or the like, and a method of manufacturing the same.

  Conventionally, various studies have been made on Fe-Ni based alloy thin plates used for lead frames, metal masks and the like in order to improve performance. For example, in Patent Document 1, in order to improve the etching accuracy, the hot-rolled sheet is cold-rolled and annealed one or more times, respectively, and the cold-pressing ratio of cold rolling before final recrystallization annealing is 90% or more, The manufacturing method of the Fe-Ni type thin plate characterized by manufacturing the annealing temperature of the final recrystallization annealing as 850 ° C or more and the final cold-pressing rate of 30% or less is disclosed. Moreover, in patent document 2, in order to obtain a favorable etching property and high intensity | strength, the cold rolling rate of 85% or more and annealing of 700 degreeC or more are performed at least once, and the rolling rate which does not exceed the said cold rolling rate after that A method of manufacturing a shadow mask material is disclosed, characterized in that the cold rolling and the annealing at a temperature not exceeding 850 ° C. are performed in this order.

Unexamined-Japanese-Patent No. 2003-253398 Japanese Patent Application Laid-Open No. 06-279946

The Fe-Ni-based alloy sheet as described above is used after being cut into a desired size depending on the application. However, due to the demand for higher precision of products, dimensional tolerances become increasingly strict even in metal masks and the like, and there is a possibility that more products will be out of dimensional tolerances after cutting. Although the inventions of Patent Document 1 and Patent Document 2 described above are useful inventions having the effect of improving the etching performance, Patent Document 1 and Patent Document 2 are related to suppressing variations in thin plate characteristics after cutting. It is not described, leaving room for consideration.
Therefore, an object of the present invention is to provide an Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less and capable of providing good shape processability with less anisotropy of mechanical characteristics of the rolling surface. An alloy sheet and a method of manufacturing the same.

In one embodiment of the present invention, Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less, by mass%, balance Is made of Fe and impurities, and a hot-rolled material having a thickness of 2 mm or more is used as a material for cold rolling, with respect to the material for cold rolling,
Carry out the first cold rolling with a rolling reduction of 85% or more,
After the first cold rolling, recrystallization annealing is performed under conditions of a temperature of 800 ° C. or higher and a holding time of 0.1 to 1.2 minutes,
After the recrystallization annealing, a final cold rolling with a rolling reduction of 40% or less is performed to obtain a Fe-Ni alloy thin plate having a thickness of 0.25 mm or less, and no heat treatment is performed after the final cold rolling. It is a manufacturing method of the Fe-Ni system alloy thin plate which

Another aspect of the present invention is
% By mass Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less, the balance being Fe and impurities, In an Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less, a difference between 0.2% proof stress in each of three directions of width direction, length direction and 45 ° direction of the Fe-Ni-based alloy thin plate is the above It is within 5% of the average value of the 0.2% proof stress in three directions, and each elongation value in the three directions is 0.90 to 1.10 times the average elongation value in the three directions. , Fe-Ni based alloy sheet.

  According to the present invention, in a thin Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less, since there is little fluctuation in mechanical properties due to the cutting direction, it is possible to exhibit good workability.

  Hereinafter, embodiments of the present invention will be described. First, the manufacturing method of the Fe-Ni-type alloy thin plate of this invention is demonstrated.

<Hot rolled material composition>
In the present invention, Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less in mass%, and the balance is Fe and A hot rolled material having a composition consisting of impurities is prepared. The Fe-Ni based alloy having the composition defined in the present invention has the composition necessary to obtain the desired thermal expansion coefficient.
[Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%)]
As mentioned above, Ni and Co are elements necessary to obtain a desired thermal expansion coefficient. If the Ni + Co content is less than 35.0%, the austenite structure tends to be unstable, while if it exceeds 43.0%, the thermal expansion coefficient rises and the low thermal expansion characteristics are not satisfied, so the Ni + Co content is 35.0 With ~ 43.0%. Co does not necessarily need to be added, but because Co has the effect of increasing the strength of the Fe-Ni alloy, it can be required to handle particularly severe handling, with a thin plate thickness up to 6.0%. In the range, part of Ni can be replaced by Co.

[Si: 0.5% or less, Mn: 1.0% or less]
Si and Mn are usually contained in trace amounts for the purpose of deoxidation in Fe-Ni alloys, but if they are contained excessively, segregation is likely to occur, so Si is made 0.5% or less, Mn is 1.0 % Or less. The lower limits of Si and Mn are not particularly limited, but as described above, since Si is added as a deoxidizing element, 0.05% of Si and 0.05% of Mn remain without much.
[The balance is Fe and impurities]
The elements other than the above elements may be substantially Fe, but include impurities which are inevitably contained in production. An impurity element which requires particular limitation is C, and for example, if it is used for etching, the upper limit thereof may be 0.05%.
Moreover, when improving press punchability, you may contain free-cutting elements, such as S, by 0.020% or less. An element such as B that improves hot workability may be contained at 0.0050% or less.

<Hot rolled material thickness: 2 mm or more>
The hot-rolled material used in the present invention has a thickness of 2 mm or more. If the thickness of the hot-rolled material is less than 2 mm, cold rolling with a rolling reduction of 85% or more specified in the present invention may not be performed. In addition, if the thickness of the hot-rolled material is less than 2 mm, special rolling equipment may be required. Therefore, in the present invention, the thickness of the hot-rolled material is 2 mm or more.
Although it is possible to increase the rolling reduction by increasing the thickness of the hot-rolled material, on the other hand, the number of passes during the cold-rolling process increases, or the shape of the Fe-Ni alloy during rolling Since adjustment may be difficult, it is realistic to set the upper limit to 5 mm in thickness.
In this hot-rolled material, an oxide layer is formed on the surface, and the thickness of the hot-rolled material is a thickness including the oxidized layer.

<Material for cold rolling>
In the present invention, the above-described hot-rolled material is used as a material for cold rolling. Since an oxide layer is formed on the hot-rolled material, the oxide layer is removed, for example, mechanically or chemically. In addition, the edges may be arranged so that defects such as cracks do not occur from the edges of the cold rolled material during cold rolling. Such processing is performed to make a material for cold rolling.

Next, the cold rolling process will be described in detail.
<First cold rolling>
In the present invention, the rolling reduction in the first cold rolling, which is cold rolling before recrystallization annealing, is 85% or more. By thus increasing the rolling reduction before recrystallization annealing, the crystal plane orientation of the alloy thin sheet obtained after final rolling described later can be easily aligned in one direction, and the anisotropy of the mechanical properties can be suppressed. In addition, since the number of cold rolling and annealing steps can be reduced, it is possible to manufacture at lower cost. If the rolling reduction is less than 85%, the mechanical properties are degraded. In addition, the number of cold rolling and annealing steps which are too low in rolling reduction increases the cost. The preferable rolling reduction is 87% or more, more preferably 90% or more. The upper limit of the rolling reduction is not particularly limited, but if the rolling reduction exceeds 99%, the cost may increase due to excessive rolling time, so it is realistic to set the upper limit to 99%.

<Recrystallization annealing>
The present invention performs recrystallization annealing at a temperature of 800 ° C. or more after the first cold rolling described above. By this process, the strain of the work-hardened thin plate is removed and softened under a strong pressure, and the desired thickness and mechanical properties are easily obtained by the final final cold rolling. If the annealing temperature is less than 800 ° C., the material may not be sufficiently softened. Further, the upper limit of the annealing temperature is not particularly limited, but if it is too high, desired properties may not be obtained, so it can be set at 1100 ° C.
Furthermore, the present invention is also characterized in that the heat holding time of annealing of the thin plate is adjusted to 0.1 to 1.2 minutes. As described above, by setting the heating and holding time to a relatively short time in the above-described temperature range, it is possible to obtain desired isotropic characteristics of yield strength and elongation without reducing production efficiency. If the annealing time is less than 0.1 minutes, the strain may not be sufficiently removed. If it exceeds 1.2 minutes, the cost may be increased due to the fluctuation of the mechanical properties of the alloy sheet and the increase of the annealing time. The lower limit of the annealing time is preferably 0.2 minutes. The upper limit of the annealing time is preferably 0.9 minutes, and more preferably 0.6 minutes for further cost reduction.
The recrystallization annealing can be performed by continuously passing the first cold rolled material through a heating furnace set to a desired temperature. For example, the first cold rolled material can be drawn out from the state of being wound in a roll, passed through a heating furnace, and wound in a roll.

<Final cold rolling>
According to the manufacturing method of the present invention, the final cold rolling with a rolling reduction of 40% or less is performed on the material after the recrystallization annealing described above to obtain an Fe-Ni-based alloy thin sheet in which the anisotropy of mechanical properties is suppressed. It is possible. When rolling is performed in excess of 40%, it is not preferable because excessive distortion tends to increase the anisotropy of mechanical properties. The lower limit of the rolling reduction is not particularly limited, but if the rolling reduction is too low, adjustment to a desired plate thickness becomes difficult, and therefore, it can be set to 15% or more. At this time, in order to make it easy to obtain the above-described mechanical properties, it is preferable to set the rolling forward tension in final cold rolling to 200 to 500 MPa, the rolling back tension to 100 to 200 MPa, and the rolling speed to 250 m / min or less. The lower limit of the rolling front tension is more preferably 250 MPa, and the upper limit of the rolling front tension is more preferably 400 MPa. Further, the lower limit of the rolling back tension is more preferably 120 MPa, and the upper limit of the rolling back tension is more preferably 180 MPa. The lower limit of the rolling speed is not particularly limited, but preferably about 100 m / min in consideration of workability. Moreover, in the final cold rolling, it is preferable to perform rolling in one pass in the final cold rolling in order to obtain desired characteristics while suppressing wrinkling of the thin plate surface.

  The thickness of the steel strip after final cold rolling is 0.25 mm or less. This is because, for example, when the Fe-Ni alloy thin plate of the present invention is used for a lead frame, it is easy to cope with the increase in the number of pins. For example, when it is used for a metal mask, it is possible to cope with high definition by etching. It is because there is. The upper limit of the preferred thickness is 0.15 mm. A more preferable upper limit is 0.1 mm, and a still more preferable upper limit is 0.08 mm. The lower limit is not particularly limited, but if the material is too thin, shape change tends to occur, so the thickness can be set to 0.02 mm. It is particularly preferable that the Fe-Ni-based alloy thin plate of the present invention has a wide width (for example, a plate width of 500 to 1200 mm).

<S strain relief annealing omitted>
In the present invention, heat treatment is not performed after the above-described final cold rolling. The heat treatment is, for example, strain relief annealing performed at a recrystallization temperature or less. By omitting the heat treatment, it is possible to suppress the change of the thin plate shape and the fluctuation of the mechanical characteristics due to the release of the residual strain. In the present invention, even if the strain is not removed by the above-mentioned manufacturing method, the mechanical property is an anisotropic product, and therefore it can be omitted. In addition, omission of heat treatment enhances the energy saving effect and is economical.

Then, the Fe-Ni-type alloy thin plate of this invention which can be obtained by the manufacturing method of this invention mentioned above is demonstrated.
<0.2% proof stress, elongation value>
The Fe-Ni-based alloy thin plate of the present invention has a width direction (a first direction of the surface of the thin plate and a direction corresponding to a direction perpendicular to the rolling direction), a length direction (a second direction of the surface of the thin plate) A direction perpendicular to the width direction, a direction corresponding to the rolling direction, a 45 ° direction (a third direction of the surface of the thin plate, a direction having a 45 ° relationship with the width direction and the length direction) The difference between each 0.2% proof stress in the three directions of 5) is 5% or less of the average value of the 0.2% proof stress in the three directions, and each elongation value in the three directions is the average of the three directions. It is characterized by being 0.90 to 1.10 times an elongation value. The 0.2% proof stress is a parameter that affects the workability such as plastic deformation, and the elongation value is a parameter that affects the product shape after processing. By adjusting the thickness within the above range, the thin plate of the present invention has good characteristics with little variation in strength and shape depending on the cutting direction, for example, variation in cutting conditions when cutting an alloy thin plate from various directions Can be suppressed to obtain good workability. When the difference between each 0.2% proof stress in the three directions exceeds 5% of the average value in the three directions, the anisotropy increases and the difference in shape due to the cutting direction increases, so depending on the cutting direction, a desired difference may occur. There is an increased possibility of generating thin plates not satisfying the characteristics. Preferably, the difference between the respective 0.2% proof stress in the three directions is set to 3% or less of the average value of the 0.2% proof stress in the three directions. The difference between each 0.2% proof stress and the difference between each elongation difference is most preferably 0% (the characteristics are the same in each direction), but it is difficult to make the difference 0%. For example, the lower limit of the difference between each 0.2% proof stress can be set to 0.1%. Further, by setting the average value of the 0.2% proof stress in three directions of the thin plate of the present invention to 580 MPa or less, the anisotropy of the alloy thin plate can be further suppressed, which is preferable. Furthermore, it is preferable in order to suppress the product shape after a cutting | judgement that the average elongation value of this invention shall be 2% or less.

<Crystal orientation>
The Fe-Ni-based alloy thin plate of the present invention preferably has a (200) plane integration degree of 90% or more. The Fe-Ni-based alloy thin plate of the present invention tends to be able to further suppress the anisotropy of the mechanical properties due to the above characteristics. In addition to the above, for example, in the case of processing a lead frame or the like by press processing, it becomes possible to manufacture regardless of the direction. More preferably, the (200) area density is 95% or more. The degree of (200) surface integration in the present embodiment is, for example, (111), (200), (220), (311) in the rolling surface of the Fe-Ni alloy thin plate using X-ray diffraction (XRD) method. X-ray diffraction integral intensities I (111), I (200), I (220), I (311) of I), and I (200) / {I (111) + I (200) + I (220) It can obtain | require by using the formula of + I (311)}.

Vacuum melting, soaking heat treatment, hot pressing and hot rolling were performed to prepare a 3.0 mm-thick hot-rolled material. The chemical composition of the hot rolled material is shown in Table 1.
The above-mentioned hot-rolled material is chemically polished and mechanically polished to remove the oxide layer on the surface of the hot-rolled material, and trimmed to remove cracks during hot rolling at both ends in the material width direction. A .55 mm cold rolling material was prepared. The width of the cold rolling material is 860 mm.
Next, the above-mentioned material for cold rolling was divided into an example of the present invention and a comparative example, and the steps shown in Table 2 were carried out to obtain an Fe-Ni based alloy thin plate. In the example of the present invention, first cold rolling, recrystallization annealing, final cold rolling, and in Comparative Example 1, intermediate rolling (1), recrystallization annealing, intermediate rolling (2), recrystallization annealing, final cold rolling And In Comparative Example 2, the process was the same as in the inventive example, but the rolling reduction at the final cold rolling was set larger than in the present invention.
The first cold rolling of the present invention example and the first cold rolling of the comparative example 2 and the intermediate rolling (1) (2) of the comparative example 1 are made of the above-described cold rolling materials, and the number of passes is as shown in Table 2. For 10 passes. Thereafter, recrystallization annealing was performed at a temperature of 900 ° C. and a holding time of 0.36 minutes for both the inventive example and the comparative example. Then, final cold rolling was performed under conditions of a rolling forward tension of 320 MPa, a rolling back tension of 140 MPa, and a rolling speed of 200 m / min. In Comparative Example 1, recrystallization annealing was performed twice. Moreover, although comparative example 3 is the same as the example of this invention until final cold rolling, the strain relief annealing was performed at the temperature of 600 degreeC after final cold rolling. The strain relief annealing after final cold rolling was not performed in the inventive example, the comparative example 1 and the comparative example 2.

  Various test pieces were extract | collected from the Fe-Ni-type alloy thin plate which finished the above-mentioned final cold rolling, and it used for each test. The results of the test are summarized in Table 3 and shown. 0.2% proof stress and elongation were performed according to the method defined in JIS-Z2241. The test piece is a JIS 13 B test piece. Further, with regard to the inventive example and the comparative example 1, the degree of (200) plane integration of the thin plate surface was measured using an X-ray diffractometer. This (200 plane) integration degree measures X-ray diffraction integral intensity I (111), I (200), I (220), I (311), I (200) / {I (111) + I (I) 200) + I (220) + I (311)} It derived using a formula. As a result, the (200) plane integration degree of the inventive example was 98%, and the (200) plane integration degree of the comparative example 1 was 68%. Thereby, it has been confirmed that the Fe-NI based alloy thin plate of the inventive example has a very high (200) surface integration degree.

As described above, in the Fe-Ni-based alloy thin plate of the present invention, the difference between each 0.2% proof stress in the width direction, the length direction, and the 45 ° direction is at most 7 MPa, which is about 1.3 of the average value. It was a value of%. The elongation values in the three directions were also about 0.92 to 1 times the average value, and it was confirmed that the alloy sheet of the present invention had excellent properties with very little anisotropy. On the other hand, in the Fe-Ni-based alloy thin plate of Comparative Example 1, the difference between each 0.2% proof stress in the width direction, the length direction and the 45 ° direction is 52 MPa at the maximum, and about 8.8% of the average value It was a value. The elongation values in the three directions were also about 0.89 to 1.13 times the average value, and it was confirmed that the anisotropy of the mechanical properties was larger than that of the alloy sheet of the invention example. The Fe-Ni-based alloy thin plate of Comparative Example 2 has a maximum difference of 0.2 MPa between each 0.2% proof stress in the width direction, length direction and 45 ° direction, and has a value of about 3.8% of the average value It was within the specified range. However, the elongation values in three directions were about 0.67 to 1.33 times the average value, and it was confirmed that the anisotropy of the elongation characteristics was higher than that of the alloy thin plate of the invention example. Also in the Fe-Ni-based alloy thin plate of Comparative Example 3, the 0.2% proof stress value was within the specified range, but it was confirmed that the elongation values in three directions were largely dispersed.

Claims (2)

% By mass Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less, the balance being Fe and impurities, A hot-rolled material having a thickness of 2 mm or more is used as a material for cold rolling, with respect to the material for cold rolling,
Carry out the first cold rolling with a rolling reduction of 85% or more,
After the first cold rolling, recrystallization annealing is performed under conditions of a temperature of 800 ° C. or higher and a holding time of 0.1 to 1.2 minutes,
After the recrystallization annealing, a final cold rolling with a rolling reduction of 40% or less is performed to obtain a Fe-Ni alloy thin plate having a thickness of 0.25 mm or less, and no heat treatment is performed after the final cold rolling. Method of manufacturing Fe-Ni based alloy sheet. % By mass Ni + Co: 35.0 to 43.0% (where Co is 0 to 6.0%), Si: 0.5% or less, Mn: 1.0% or less, the balance being Fe and impurities, In an Fe-Ni-based alloy thin plate having a thickness of 0.25 mm or less, a difference between 0.2% proof stress in each of three directions of width direction, length direction and 45 ° direction of the Fe-Ni-based alloy thin plate is the above It is within 5% of the average value of the 0.2% proof stress in three directions, and each elongation value in the three directions is 0.90 to 1.10 times the average elongation value in the three directions. , Fe-Ni based alloy sheet.