JPH0657384A - Fe-ni alloy thin sheet and fe-ni-co alloy thin sheet for shadow mask excellent in press-formability and production thereof - Google Patents

Abstract

(57) [Summary] [Object] To provide a Fe-Ni alloy thin plate for a shadow mask and a Fe-Ni-Co alloy thin plate, which are preferable for use in a color cathode ray tube, and a method for producing the same. [Constitution] wt%, Ni: 30-38%, Si: 0.05% or less, B: 0.00
05% or less, O: 0.0020% or less, N: 0.0015% or less, Co: 6%
Containing the following, the balance consisting of Fe and unavoidable impurities, the alloy plate average austenite grain size after annealing before press forming is 15 to 45 μm, the austenite grain mixed grain size is 50% or less, and the crystal to the alloy plate surface The degree of surface integration satisfies a predetermined value.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an Fe-Ni alloy thin plate and an Fe-Ni-Co alloy thin plate having excellent press formability and a method for producing them, which is preferable for a shadow mask used in a color cathode ray tube. Ni alloy sheet and Fe-Ni
It is an object of the present invention to provide a Co alloy thin plate and a manufacturing method thereof.

[0002]

2. Description of the Related Art In recent years, with the increasing quality of color televisions,
As an alloy for a shadow mask that can deal with the problem of color misregistration, an Fe-Ni-based alloy containing 34 to 38 wt% Ni (hereinafter referred to as "conventional Fe-Ni-based alloy") is used. This conventional Fe-Ni alloy has a remarkably small coefficient of thermal expansion as compared with the low carbon steel conventionally used as a shadow mask material. Therefore, if the shadow mask is made of the conventional Fe-Ni alloy, even if the shadow mask is heated by the electron beam, the problem of color shift due to thermal expansion of the shadow mask is unlikely to occur.

Alloy thin plates for shadow masks are generally
It is manufactured by the following steps. That is, an alloy ingot is prepared by a continuous casting method or an ingot making method, and then the alloy ingot thus prepared is subjected to slab rolling, hot rolling and cold rolling / annealing to produce an alloy thin plate. It is a thing.

The alloy thin plate for a shadow mask manufactured as described above is usually processed into a shadow mask by the following steps. That is, through a photoetching on the alloy thin plate for the shadow mask, the electron beam passage hole (hereinafter,
Simply called "holes") (hereinafter the alloy thin plate for shadow masks that has been punched by etching is called "flat mask"), then annealed the flat mask, and then annealed the flat mask. , Press-formed into a curved shape to match the shape of the cathode ray tube, then, this is assembled into a shadow mask, and then the surface thereof is subjected to blackening treatment.

However, when the conventional general Fe-Ni alloy as described above is used, this alloy has higher strength and mechanical in-plane anisotropy than the conventional low carbon steel shadow mask. Because of this, cold rolling of this alloy, after recrystallization annealing, the shadow mask material produced by finish rolling is subjected to annealing before pressing after etching perforation, and during subsequent press molding processing, shape freeze defects, Many troubles such as cracking of the material and unevenness of transmission occurred, which was a great disadvantage in the manufacture of the cathode ray tube.

Therefore, as a method for reducing the strength of such a material, there is a proposal as disclosed in JP-A-3-267320. That is, this technique is cold rolling followed by recrystallization annealing, followed by finish cold rolling in the range of 5 to 20% of reduction, and by annealing at a temperature of less than 800 ° C., 0. 2% proof stress is 9.5kgf / mm ² (10kgf
/ Mm ² ) or less), and the strength is reduced to a level with good press formability (hereinafter referred to as prior art 1).

Further, as a method for reducing the in-plane anisotropy which is a mechanical property of a material, there is the following prior art. That is, in Japanese Unexamined Patent Publication No. 64-52024, the combination of cold rolling and recrystallization annealing is repeated two or more times, and the final step is a final masking step in a method of manufacturing a shadow mask material by a hardness-added cold rolling step. By cold rolling immediately before the crystal annealing step to a cold rolling rate of 40 to 80%, a shadow mask original plate having a small in-plane anisotropy of elastic modulus is obtained. When this original plate is used for press forming after annealing after etching, the etching hole deformation is small, and uneven gloss and streak-like defects do not occur, resulting in excellent uniform deformability during press forming (hereinafter referred to as prior art. 2).

[0008]

However, in the above-mentioned prior art 1, under the above-mentioned annealing conditions, the strength is reduced to a level at which the press formability is satisfactory. It was not enough to satisfy all the quality. That is, the shadow mask material according to the above-described technique was likely to have galling on the mold during press molding, and cracks were likely to occur at the end of the shadow mask. In addition, the in-plane anisotropy of the material obtained by this technique is large, and there are often cases in which transmission unevenness of the shadow mask occurs after the press forming process, which is a quality problem.

Further, in the above-mentioned prior art 2, the in-plane anisotropy of the elastic coefficient of the material is small, and the occurrence of uneven transmission during press molding does not pose a problem. However, even with this technique, the occurrence of cracks at the edge of the shadow mask during the above-mentioned press forming is a problem.

Furthermore, with the recent trend toward higher brightness and flatter screens of color TVs, the quality requirements for color shifts on the screens have become more severe.
Even in a cathode ray tube using a shadow mask manufactured by one of the prior arts, a problem that a color shift is partially generated during electron beam irradiation (when a TV is used) often occurs.

[0011]

SUMMARY OF THE INVENTION The present invention has been devised through repeated studies in view of the above-mentioned circumstances, and has excellent press formability, and in particular, is well compatible with a mold (to a mold). Fe-for shadow masks, which prevents cracking and transmission unevenness during press molding and also suppresses partial color misregistration when the shadow mask is used in TVs.
The present invention succeeds in providing a Ni alloy thin plate, a Fe-Ni-Co alloy thin plate, and a method for producing them, and is as follows.

(1) wt%, Ni: 34-38%, S
i: 0.05% or less, B: 0.0005% or less, O: 0.0
020% or less, N: 0.0019% or less, the balance
The alloy sheet is composed of Fe and unavoidable impurities and has an average austenite grain size D of 15 to 45 μm before annealing after press forming. An Fe-Ni alloy thin plate for a shadow mask excellent in press formability, which is below and has a crystal plane integration degree on the surface of the alloy plate satisfying the values in the following table. (However, D is the average austenite crystal grain size in the alloy plate. D _max is the maximum austenite crystal grain size in the alloy plate.

[0013]

[Table 4]

(2) wt%, Ni: 34 to 38%, Si: 0.
07% or less, B: 0.0005% or less, O: 0.0020
% Or less, N: 0.0019% or less, Co: 1.0% or less, and the balance is Fe and inevitable impurities.
Moreover, the average austenite grain size D of the alloy sheet before press forming and after annealing is 15 to 45 μm, and An Fe-Ni-Co alloy thin plate for a shadow mask excellent in press formability, which is below and the degree of crystal plane integration on the surface of the alloy plate satisfies the values in the following table. (However, D is the average grain size of austenite in the alloy plate. D _max is
Maximum grain size of austenite in alloy plate.

[0015]

[Table 5]

(3) wt%, Ni: 30-38%, Si: 0.
07% or less, B: 0.0005% or less, O: 0.0020
% Or less, N: 0.0019% or less, Co: 1.0% or more and up to 6%, and the balance is Fe and inevitable impurities, and the average austenite crystal of the alloy plate before press forming and after annealing. Particle size D is 15-45 μm, An Fe-Ni-Co alloy thin plate for a shadow mask excellent in press formability, which is below and the degree of crystal plane integration on the surface of the alloy plate satisfies the values in the following table. (However, D is the average grain size of austenite in the alloy plate. D _max is
Maximum grain size of austenite in alloy plate.

[0017]

[Table 6]

(4) The hot-rolled steel strip of the low thermal expansion alloy having the components described in the above items (1) to (3) is annealed, and then cold-rolled (CR ₂ ) followed by re-rolling. After the crystal annealing, the hot-rolled sheet annealing is performed at 810 ° C. to 890 when manufacturing in a process of performing strain relief annealing after finish cold rolling (CR ₃ ).
The rolling reduction (CR ₂ %) in cold rolling is 81 to 94
%, Reduction ratio (CR ₃ %) in finish cold rolling is 16 to 29%
The annealing before press forming is performed at a temperature (T ° C) of 740 to 900 ° C and a time (tmin) of
The average austenite crystal grain size of the alloy plate after annealing, the mixed grain size of the austenite crystal grains, and the degree of integration of crystal planes on the surface of the alloy plate are claimed under the conditions of 2 to 40 min and T ≧ -123 log t + 937. The Fe-Ni alloy thin plate for a shadow mask and the Fe-Ni-Co alloy thin plate having excellent press formability, characterized by satisfying the above value.

(5) After hot-rolled sheet annealing of a hot-rolled steel strip of a low thermal expansion alloy having the components described in (1) to (3) above, 1
Next cold rolling (CR ₁ ) and subsequent recrystallization annealing, then secondary cold rolling (CR ₂ ) and recrystallization annealing, then finish cold rolling (CR ₃ ), and later strain relief At the time of manufacturing in the annealing process, the hot-rolled sheet annealing is performed at 810 to 890 ° C., and the reduction ratio (CR ₁ %) in the primary cold rolling is 40 to 55.
%, The reduction ratio (CR ₂ %) at the reduction ratio in the secondary cold rolling is 8
1 to 94%, the reduction ratio (CR ₃ %) in finish cold rolling is 1
Each of the annealing is performed within a range of 6 to 29%, and the subsequent annealing before press forming has a temperature (T ° C) of 740 to 900 ° C, a time (Tmin) of 2 to 40 min, and T ≧ -123 log t +.
Provided that the average austenite crystal grain size of the alloy plate after annealing, the mixed grain size of the austenite crystal grains, and the degree of integration of crystal planes on the surface of the alloy plate satisfy the value of claim 1 under the condition of satisfying 937. Fe-Ni alloy thin plate for shadow masks and Fe-Ni with excellent press formability characterized by
─ Method for manufacturing Co alloy sheet.

[0020]

The present invention as described above will be further explained. From the above viewpoints, the present inventors have found that a shadow which is excellent in press formability and which suppresses the occurrence of partial color misregistration when used in a color television. As a result of intensive studies to develop the Fe-Ni alloy thin plate and the Fe-Ni-Co alloy thin plate for the mask, the following findings were obtained. That is, Fe-Ni for shadow mask
Chemical composition of Fe-based alloy sheet and Fe-Ni-Co alloy sheet,
Furthermore, by adjusting the austenite crystal grain size, its mixed grain size, and the crystal orientation within a predetermined range, it is possible to impart the required press molding quality and suppress the occurrence of the partial color misregistration described above. .

More specifically, the inclusion of B and O within a predetermined range enhances the growth of crystal grains in the annealing before pressing under the conditions characterized by the present invention, so that the predetermined austenite grain size is obtained. The shape fixability at the time of press molding is given by the above, and the inclusion of Si and N within the predetermined range improves the compatibility with the mold at the time of press molding (prevents the occurrence of galling on the mold). Further, by setting the degree of integration of {211} crystal planes on the surface of the alloy sheet after annealing before pressing within a predetermined range, the occurrence of cracking of the material during press forming is suppressed.

Further, by controlling the mixed grain size of the austenite crystal grains after the pre-press annealing to be within a predetermined range, it is possible to suppress the occurrence of transmission unevenness at the time of press forming, and it is possible to By setting the integration degree of the 210} and {331} crystal planes within a predetermined range, the occurrence of the partial color shift described above is suppressed.

Furthermore, the present inventors have obtained the following findings. That is, in the manufacturing process of the present alloy, the hot-rolled steel strip is annealed at a predetermined temperature before cold-rolling the hot-rolled steel strip, and further in the subsequent cold-rolling, the cold-rolling rate and finish cold-rolling rate and before pressing By setting the annealing conditions (temperature, time) of the alloy sheet within a predetermined range, the average austenite grain size of the alloy sheet after annealing before pressing and the {331}, {21}
0}, {211} crystal plane integration can be adjusted within a predetermined range ({331} on the alloy plate surface, {21
0}, {211} crystal plane integration is simply {33
1}, {210}, and {211} crystal planes are referred to as the degree of integration, respectively.

Further, in order to bring the mixed grain size of the austenite crystal grains in the alloy thin sheet after the pre-press annealing to a predetermined range, the rolling ratio in the cold rolling once or twice after the hot-rolled sheet annealing is set to the predetermined range. Within is especially important.

The present invention was made based on the above-mentioned findings, and Fe-Ni for shadow mask according to the present invention is used.
Chemical composition in alloy sheet and Fe-Ni-Co alloy sheet,
Austenite grain size and its grain size after annealing before pressing, and {331}, {210} on the alloy plate surface,
The reason why the degree of {211} crystal plane integration is limited to the above range is as follows.

(1) Nickel: Required for Fe-Ni alloy thin plates for shadow masks in order to prevent color shift.
The upper limit of the average coefficient of thermal expansion in the temperature range of 30 to 100 ° C is 2.0 x 10 ^-6 / ° C. The coefficient of thermal expansion depends on the nickel content of the alloy sheet. And, the range of nickel content satisfying the above-mentioned condition of the average thermal expansion coefficient is in the range of 34 to 38 wt%. Therefore, the nickel content should be limited to within the range of 34-38 wt%. Even within such a range of Ni content, the preferable Ni content that can reduce the average thermal expansion coefficient is 35 to 37%, and the more preferable Ni content that can further reduce the average thermal expansion coefficient is 35%. It is 0.5 to 36.5%.

Even when Co is contained at 0.001 to 1.0%, the Ni value satisfying the upper limit of the average thermal expansion coefficient is 34 to 38%. Even in such a case, the preferable Ni content for lowering the average coefficient of thermal expansion is 35 to 37%. In addition, when the content of Co exceeds 1.0% to 6.0%,
The range of Ni content satisfying the above-mentioned average thermal expansion coefficient is 3
0 to 38%, and in the Fe-Ni-Co alloy, Ni
By adjusting the amount to 30-33% and the Co amount to 3-6%,
The average coefficient of thermal expansion is even lower, which is excellent.

In the present invention, the average austenite grain size required for improving the shape fixability during press forming, suppressing cracking of the alloy sheet, and preventing permeation unevenness after press forming is the same as that for warm pressing. Assuming that 15 to 15
It is 45 μm. If it is less than 15 μm, the shape fixability is poor and the alloy plate may crack. On the other hand, when it exceeds 45 μm, cracks occur and uneven transmission occurs after press forming. From the above, the average austenite grain size was determined to be 15 to 45 μm.

In order to suppress the occurrence of material cracking, the degree of integration of {211} crystal faces on the surface of the alloy plate is controlled to a specific value while maintaining the above-mentioned average austenite grain size, as described later. Is essential. However, in order to enhance the growth of the crystal grains under the annealing conditions before pressing intended in the present invention, it is necessary to control O and B to be equal to or less than a specific value and to improve the familiarity of the mold at the time of press molding. , N each need to be controlled below a specific value,
It is as follows.

(2) Oxygen: Oxygen is one of the impurities inevitably mixed in the alloy. When this oxygen content increases, the amount of oxide-based non-metallic inclusions in the alloy increases, and these inclusions are particularly prone to crystal grain growth during annealing before press forming at 740 to 900 ° C. for 40 minutes or less. Inhibit. That is, if the amount of O exceeds 0.0020%, the above-mentioned inhibitory effect on grain growth becomes remarkable, and the austenite crystal grain size intended in the present invention cannot be obtained. Therefore, 0.0020% was made the upper limit. The lower limit is not specified, but is 0.0001% from the economical aspect of melting.

(3) Boron: In the present alloy, boron improves hot workability, but when the content is high, boron segregates at the grain boundaries of recrystallized grains formed during annealing before pressing, and grain boundaries Of the austenite grains are not easily obtained after annealing before press forming. In particular, under the annealing conditions before pressing specified in the present invention, such a grain growth inhibitory action is strong, and this action does not work uniformly for all crystal grains, resulting in a significant mixed grain size. It shows a structure and unevenness of elongation of the material occurs during press molding, which causes unevenness of transmission.

Further, this B also increases the degree of integration of the {211} crystal faces, which causes cracking of the material skirt, after annealing. If the amount of B exceeds 0.0005%, the above-mentioned inhibitory effect on grain growth becomes remarkable, the austenite crystal grain size intended by the present invention cannot be obtained, and problems such as transmission unevenness during pressing occur. The degree of integration of the {211} crystal plane also exceeds the upper limit specified in the present invention. From the above, the upper limit of the amount of B was set to 0.0005%.

(4) Silicon: Silicon is used as a deoxidizing element during melting of the present alloy. If it exceeds 0.05%, a Si oxide film is formed on the alloy surface during annealing before pressing, Due to this oxide film, the compatibility with the mold at the time of press molding becomes poor, and the alloy comes to bite the mold. Therefore Si
The upper limit of the amount was set to 0.05%. Even if Si is 0.05% or less, the fit between the alloy plate and the mold can be further improved by further reducing the Si content. The lower limit is not specified, but is 0.001% or more from the economical aspect of melting.

(5) Nitrogen: Nitrogen is an element that is inevitably mixed when the alloy is melted. If it exceeds 0.0019%,
N is concentrated on the surface of the alloy during annealing before pressing, and the nitride on the surface of the alloy makes the alloy less compatible with the metal mold during press molding, and the alloy plate will bite the metal mold. Therefore, the upper limit of the amount of N is set to 0.0019%. The lower limit is not specified, but is 0.0001% or more from the economical aspect of melting.

The shadow mask alloy according to the present invention has a basic composition of Fe-Ni alloy and Fe-Ni-Co alloy with specific amounts of B, O, Si and N as described above, and before pressing. Average austenite grain size after annealing is 15 to 45
μm, mixed grain size of austenite grains is 30% or less {21
1}, {331}, and {210} crystal planes are characterized by having an integration degree of 20% or less, 35% or less, and 16% or less, respectively. In addition to the above composition, C: 0.0001 to 0 .
0040%, Mn: 0.001 to 0.35%, Cr: 0.001 to
It is preferably within the range of 0.05% and H: 1.3 ppm or less.

By controlling the components as described above and adjusting the average austenite grain size after pre-press annealing within the definition of the present invention, it is possible to suppress the galling of the present alloy into the die during press forming and to reduce the shape. Although the freezeability can be made to an excellent level, the cracking of the material still poses a problem in terms of press molding quality. Therefore, the present inventors
In order to solve such a problem, the relationship between the components within the definition of the present invention and the crystal orientation of the present alloy sheet having the average austenite crystal grain size was variously changed and the relationship with the crack of the material during press forming was investigated. As a result, in order to suppress cracking of the present alloy material, it is effective to control the degree of integration of {211} crystal faces to a specific value or less in addition to the regulation of the average austenite crystal grain size after annealing before pressing. I found it.

FIG. 1 shows the relationship between alloy plate cracking during press forming, the degree of accumulation of {211} crystal faces, and the average austenite crystal grain size for alloy plates having the components shown in the figure. The degree of integration of the {211} crystal planes was measured by measuring the relative X-ray diffraction intensity ratios of the (422) diffraction planes of the alloy sheet after annealing before pressing to (111), (200), (220), (31).
It was obtained by dividing by the sum of the relative X-ray intensity ratios of the diffraction surfaces of 1), (331), (420) and (422). The {211} crystal plane integration is measured by diffraction of the {422} plane, which is azimuthally the same as this crystal plane.

The relative X-ray diffraction intensity ratio is the X-ray diffraction intensity measured on each diffraction surface divided by the theoretical X-ray diffraction intensity of that diffraction surface. For example, the relative X-ray diffraction intensity ratio of the (111) diffraction plane is obtained by dividing the X-ray diffraction intensity of the (111) diffraction plane by the theoretical X-ray diffraction intensity of the (111) diffraction plane. The degree of integration of {331} and {210} crystal planes, which will be described later, is measured in the (331) diffraction plane and (420) plane, respectively.
The relative X-ray diffraction intensity ratio of the diffractive surface (this is equivalent to the {210} crystal plane in terms of the direction) is the relative X-ray intensity ratio of the seven diffractive surfaces from (111) to (422) described above. It is calculated by dividing by the sum.

As shown in FIG. 1, the average austenite crystal grain size is 15 to 45 μm, the degree of integration of {211} crystal faces is 20% or less, and cracks and uneven transmission of the alloy plate occur during press forming. Therefore, the excellent effect intended by the present invention is exhibited. From the above examination results, the degree of integration of {211} crystal faces was set to 20% or less as a condition for suppressing cracking of the alloy sheet.

Control of the mixed grain size of the austenite crystal grains after the pre-press annealing is necessary to prevent the occurrence of uneven transmission during press forming. 2 is a component within the scope of the present invention,
Average austenite crystal grain size, {331}, {21
Using an alloy plate having a degree of integration of 0} and {211} crystal faces, the relationship between the occurrence rate of transmission unevenness after press forming and the mixed grain size of austenite crystal grains was investigated. From this figure, it can be seen that when the mixed grain size of the austenite crystal grains exceeds 50%, the transmission unevenness occurrence rate becomes high. From the above, 50% or less was set as the mixed grain size range of the austenite crystal grains that suppresses the occurrence of transmission unevenness after press molding.

As described above, O, B, and
By prescribing the Si and N, the average austenite grain size after annealing before pressing and the mixed grain size thereof, and the degree of integration of {211} crystal faces, the press forming quality intended in the present invention can be made excellent. it can.

In order to suppress the occurrence of partial color shift as described above, it is important to control the degree of integration of {331} crystal faces and {210} crystal faces after pre-press annealing. That is, the {331} crystal face after annealing before pressing,
When the degree of integration of {210} crystal planes exceeds 35% and 16%, partial color misregistration occurs. Therefore, in the present invention, the degree of integration of the {331} and {210} crystal planes is determined to be 35% or less and 16% or less, respectively.

{331}, {21 after pre-press annealing
0} and {211} crystal plane integration degrees of 35% or less, 16
% Or 20% or less, in the production of an alloy thin plate, from the solidification to the hot working and the subsequent cold rolling / annealing process, the {331}, {210}, and {211} crystal planes should be minimized. This is achieved by adopting manufacturing conditions that do not allow integration. For example, when the present alloy is produced from a hot-rolled steel strip obtained by slab-rolling and hot-rolling an ingot or continuously cast slab, the hot-rolled steel strip is used as a raw material, and thereafter, hot-rolled sheet annealing-cold Cold rolling-recrystallization annealing-finishing cold rolling-strain relief annealing,
After that, in manufacturing by a step of performing annealing before press forming and then performing a blackening treatment after press forming, first, appropriate hot rolled sheet annealing may be performed after hot rolling {331},
It is effective to prevent the {210} and {211} crystal planes from accumulating. At this time, the temperature of the hot rolled sheet annealing is 810 to 89.
By selecting an appropriate temperature within the range of 0 ° C, {33
The integration degree of the 1}, {210}, and {211} crystal planes can be set to be equal to or less than the specified value of the present invention.

From the above, the integration degree of the {331} crystal plane is 35% or less, and the integration degree of the {210} crystal plane is 16%.
% Or less, the degree of integration of {211} crystal planes can be set to a value of 20% or less.
I decided.

Such hot-rolled sheet annealing in the present invention is exhibited when the hot-rolled steel strip of the present alloy is sufficiently recrystallized before the hot-rolled sheet annealing. Further, in order to obtain the degree of integration of {331}, {210}, and {211} crystal planes intended in the present invention, the slab homogenization heat treatment after slabbing is not preferable in producing the present alloy. For example, when the above-mentioned homogenizing heat treatment is performed at 1200 ° C. or higher for 10 hours or longer, one or more of {331}, {210}, {211} and the degree of integration of crystal planes have the specified values of the present invention. Such processing must be avoided as it will exceed the limit.

Further, in the case of manufacturing with the above-mentioned hot rolled steel strip, in the above-mentioned series of steps, cold rolling / annealing conditions, final cold rolling conditions, strain relief annealing conditions, and pre-press annealing conditions can be optimized. 331}, {210}, and {211} crystal planes are required to be less than or equal to the specified values of the present invention and to be a mixed grain size of austenite crystal grains within the scope of the present invention.

After the hot-rolled sheet is annealed, it is important to optimize the cold-rolling / annealing conditions in order to control the mixed grain size of the austenite crystal grains after the pre-press annealing. That is, FIG. 3 shows the relationship between the cold rolling rate (CR ₂ %) when the number of cold rolling / annealing after hot-rolled sheet annealing is 1 and the mixed grain size of austenite crystal grains after annealing before pressing. Is.

From FIG. 3, when the cold rolling annealing process is performed once, the cold rolling ratio (CR ₂ ) is within the range of 81 to 94%, and the mixed grain size of the austenite crystal grains is 50% or less, which is within the range of the present invention. On the other hand, when CR ₂ is less than 81% or more than 94%, the mixed particle size is more than 50%. From these, the mixed grain size in the case of one cold rolling annealing process is 50%.
As range for less, CR _2: defining a 81 to 94%.

FIG. 4 is a diagram showing the relationship between the cold rolling rate and the mixed grain size of austenite crystal grains when the number of cold rolling / annealing is two. From this figure, it is clear that when the cold rolling rate (CR ₂ ) is in the range of 81 to 94% and the cold rolling rate (CR ₁ ) is 40 to 55%, the mixed particle size shows a more excellent value. . From the above,
When the cold rolling annealing process is performed twice, CR ₁ : 40 to 55%,
CR ₂ : It was defined as 81 to 94%. Cold rolling (CR ₁ , CR
₂ ) After recrystallization annealing at 810-840 ℃, 0.5-3 min
It is desirable to perform under the conditions of. Even if the annealing temperature is higher than the recrystallization temperature, a mixed grain structure is exhibited in annealing at 810 ° C. or lower, so that the mixed grain size of austenite crystal grains becomes high even after annealing before pressing. Moreover, even in the range of 810 to 840 ° C.
Annealing for less than 5 min results in a mixed coarse structure, while annealing for more than 3 min results in a coarse grained structure, and in any case, the mixed grain size of austenite crystal grains increases after pre-press annealing, which is not preferable.

When the cold rolling / annealing conditions within the scope of the present invention described above are adopted, {331}, {210}, {211}.
The degree of integration of crystal planes is 35% or less, 16% or less,
It will be 20% or less.

When the finish cold rolling ratio is within the range of 16 to 29%, when the components within the stipulations of the present invention, the cold rolling / annealing conditions, and the annealing conditions before press molding are adopted, after the annealing before press molding, , Average austenite crystal grain size is 15 to 45 μm, mixed grain size of austenite crystal grain is 50% or less, {331}
Degree of integration of crystal plane ≦ 35%, degree of integration of {210} crystal plane ≦
16%, the degree of integration of {211} crystal planes ≦ 20%. Furthermore, if the finish cold rolling rate is less than 16% or more than 29%, one or more of the characteristics characteristic of the present invention described above do not satisfy the scope of the present invention. Therefore, the finish cold rolling rate is 16 to 29.
%.

In the present invention, the average austenite crystal grain size, the mixed grain size of the austenite crystal grains, and the degree of integration of {331}, {210}, and {211} crystal planes described above are pressed within the scope of the present invention. It is also important to optimize the previous annealing conditions. This will be described with reference to FIG. 5. FIG. 5 shows components, hot rolled sheet annealing conditions, cold rolling / annealing conditions,
Average cold austenite grain size after pre-press annealing of alloy sheet having a finish cold rolling rate within the range of the present invention, mixed grain size of austenite grains, {331}, {210}, and {211} crystal plane accumulation and pressing. It shows the relationship between the temperature (T, ° C) and the time (t, min) of the pre-annealing.

As is apparent from FIG. 5 as described above, even when the conditions other than the pre-press annealing condition are within the scope of the present invention, when T <−123 log t + 937, the average austenite grain size is 15 μm. And the degree of integration of {211} crystal planes exceeds 20%, which is unsuitable. If T is higher than 900 ° C, the average austenite grain size is 45
Insufficient integration of more than 20 μm and the {211} crystal plane is more than 20%, and if t is more than 40 min, {21
1}, {331}, {210} of the integration degree of the crystal plane 1
One or more are not suitable because they are accumulated beyond the scope of the present invention.

From the above, the average austenite crystal grain size intended for the present invention, the mixed grain size of austenite crystal grains, {3
31}, {210}, and {211} crystal planes are integrated under the conditions of T: 740 to 900 ° C. and t: 2 to 40 min.
, T ≧ −123 log t + 937. The strain relief annealing performed in the present invention is important for controlling the degree of integration of the {331}, {210}, and {211} crystal faces in the pre-press annealing that is performed thereafter. The condition of the strain relief annealing for sufficiently exerting the effect intended by the invention is 0.5 to 300 seconds at 450 to 540 ° C.

Further, in addition to the above-mentioned method, the method of keeping the degree of integration of {331}, {210}, {211} crystal planes in the present alloy thin plate after annealing before press forming within the scope of the present invention is not limited to the rapid solidification method. Adoption, texture control by recrystallization control in hot working, etc. Furthermore, the annealing before press forming in the present invention may be performed before photoetching. In this case, if the annealing conditions before press forming are within the scope of the present invention, the required photoetching quality can be secured.

[0056]

EXAMPLES The present invention as described above will be described in more detail with reference to specific examples as follows. (Example 1) First, the present inventors, by ladle refining,
Alloy Nos. 1 to N having the chemical compositions shown in Tables 7 and 8 below
Each steel ingot consisting of o.21 was adjusted.

[0057]

[Table 7]

[0058]

[Table 8]

Each of the ingots shown in Table 1 as described above was cared for, then subjected to slab rolling, surface flaw removal and hot rolling (heating was 1100 ° C. × 3 hr), and the hot-rolled steel strip obtained was used. ,
After that, hot-rolled sheet annealing (860 ° C) -cold rolling (93.0%)
-Annealing (810 ° C x 1 min) -finish cold rolling (reduction ratio 2
1%)-Strain relief annealing (530 ° C x 0.5 sec),
An alloy plate with a plate thickness of 0.25 mm was obtained, and each of the above alloys No. 1 to No. 2
No. 1 was obtained as materials No. 1 to No. 21, respectively. The hot-rolled steel strip was sufficiently recrystallized after hot-rolling.

Material Nos. 1 to 1 obtained as described above
Material No. 1 to No. 3, No. 5 to No. 21 in No. 21
After making each alloy plate into a flat mask by etching, the flat mask is subjected to pre-annealing under the conditions shown in Table 9 below, and then press-molded to obtain shape fixability, conformability with a die, and material. The frequency of occurrence of cracking and transmission unevenness was examined according to the evaluation criteria shown in Tables 5 and 6 below.

[0061]

[Table 9]

It was confirmed that the above-mentioned flat mask after etching had no unevenness and had the required etching performance, and the average austenite crystal grain size and its mixed grain size were examined after the pre-press annealing. Tensile properties (n
Value, r value, elongation value) and {331}, {210},
The degree of integration of {211} crystal planes was examined after press annealing and tensile properties were measured at room temperature. Furthermore, {331}, {21
The degree of integration of the 0} and {211} crystal planes was measured by the above-mentioned method by X-ray diffraction.

Further, the alloy plate of material No. 4 was subjected to strain relief annealing under the above-mentioned conditions, pre-press annealing under the conditions shown in Table 2, followed by etching, forming a flat mask, and press forming. There is. The characteristic values of this material are examined in the same manner as the other materials described above. The occurrence of partial color misregistration was investigated after the press-molded shadow mask was blackened, incorporated into a cathode ray tube, and irradiated with an electron beam for a predetermined time.

As is apparent from the results shown in Tables 7 and 8 as described above, {331}, {210}, which has a component composition within the scope of the present invention and within the scope of the present invention,
Each of the materials No. 1 to No. 13 and No. 13-1 having the degree of accumulation of {211} crystal faces and the average grain size of austenite grains and the mixed grain size of austenite grains was excellent in press molding quality. It shows the level and there is no partial color shift. The material of No. 4 was subjected to etching after annealing before pressing, but the flat mask had no unevenness and required edge performance. Thus, No. 13-1 steel containing Co exhibits similarly excellent properties.

On the other hand, Material 14 and No. 16
Each of the above-mentioned materials has a Si content and an N content that exceed the stipulations of the present invention, and has a problem in compatibility with a mold. Material No.
No. 15 is the case where the amount of O exceeds the regulation of the present invention, the average austenite crystal grain size is less than the regulation range of the present invention (hereinafter, simply referred to as the average grain diameter), the shape fixability is poor, and cracks in the alloy plate occur. In addition, the mixed grain size of austenite crystal grains (hereinafter simply referred to as the mixed grain size) exceeds the specified value of the present invention, uneven transmission occurs, and there is a problem in press molding quality.

The No. 17 and No. 18 materials are the cases where only the B content or the B content and the O content exceed the regulations of the present invention, the average particle size is 15 μm or less, and the shape fixability is poor. ing. Furthermore, the mixed particle size of these materials is more than 50%, and uneven transmission occurs. In addition, the degree of integration of {211} crystal planes is more than 20%, cracking of the alloy plate has occurred, and there is a problem in press molding quality.

In addition, the materials No. 19 and No. 20 have a {210} crystal plane integration degree and a {331} degree, respectively.
This is a case where the degree of integration of crystal planes exceeds the value specified in the present invention, and partial color misregistration occurs, which causes a problem in screen quality.
Further, the material No. 21 has an average particle size of more than 45 μm, the alloy plate is cracked, and the transmission unevenness is generated, which causes a problem in press molding quality. In this case,
The degree of integration of the {211} crystal plane was also over 20%, and it was confirmed that the degree of integration became stronger as the average grain size increased under the pre-press annealing condition of this crystal orientation of 920 ° C. × 40 min. Has been.

As is clear from the above description, the composition of components within the scope of the present invention and {33 within the scope of the present invention.
1}, {210}, {211} crystal plane integration, average grain size, and mixed grain size make the Fe-Ni for shadow masks excellent in press molding quality and screen quality intended in the present invention. It is clear that a system alloy sheet and a Fe-Ni-Co system alloy sheet can be obtained.

(Example 2) Using the hot-rolled steel strips of alloys No. 1 to No. 13 and No. 13-1 used in the above-mentioned Example 1, the hot-rolled sheet was annealed thereafter (see Table 10 and Table 10 below). the conditions shown in Table 11 implementation) alms, then subjected to cold rolling at a reduction ratio shown in tables 9 and 10 (no numeric CR ₁ is, CR ₂
It means that cold rolling was performed once at the reduction ratio described in (1). If both CR ₁ and CR ₂ have numerical values, it means that cold rolling was performed twice at the respective reduction ratios), and after cold rolling, each was annealed at 810 ° C x 1 min. Then, finish cold rolling (performed at the rolling reduction indicated by CR ₃ in Tables 6 and 7) is performed, and strain relief annealing (530 ° C) is performed.
X 0.5 sec), and an alloy plate with a thickness of 0.25 mm (Material No. 2
2 to No. 47) were obtained.

[0070]

[Table 10]

[0071]

[Table 11]

Of these materials No. 22 to No. 39, N
o. No. 41 to No. 42 and No. 44 to No. 47 alloy plates were etched into flat masks, and then the flat masks were subjected to pre-press annealing under the conditions shown in Table 5, and then press formed. Then, the press forming quality shown in Table 3 and the occurrence of partial color misregistration were examined. The measuring method of each characteristic value in Table 5 is the same as that of the first embodiment. It was confirmed that the above-described flat mask after etching had no unevenness and had the required etching performance.

Further, the alloy plates of the materials No. 40 and No. 43 were subjected to pre-press annealing under the conditions shown in Table 3 after the strain relief annealing under the above conditions, followed by etching to form a flat mask, Press molding is performed. The characteristic values of this material are also examined in the same manner as the other materials described above.

As is clear from Tables 8 and 9 above,
It has a component composition within the scope of the present invention, hot rolled sheet annealing conditions, cold rolling conditions (CR ₂ ,% and / or CR ₁ ,%), finish cold rolling rate (CR ₃ %), pre-press annealing conditions (temperature T, ° C, and time t, min) are within the range defined by the present invention, and have {331}, {210}, {211} crystal plane integration, average grain size, and mixed grain size within the scope of the present invention. Material No. 31-N
o. Each material of 47 shows excellent press molding quality,
No partial color shift occurs. Material No. 40 and
No. 43 was etched after annealing before pressing, but the flat mask had the required etching performance without unevenness. As described above, the No. 47 material containing Co similarly exhibits excellent properties.

Further, among the above-mentioned invention examples, the material No.
32, No. 35 to No. 37, No. 39, No. 43 to No.
Each material of 45 is a case where cold rolling is performed twice,
By performing the first cold rolling (CR ₁ ) in the range of 40 to 55%, the mixed grain size is obtained by cold rolling only once (Material No. 31, No. 33 to No. 34). , No. 38, No.
40 to No. 42, No. 46), it is clear that it shows a lower and preferable level.

On the other hand, materials No. 22 and No. 2
In No. 3, the annealing temperature of the hot-rolled sheet is lower than the lower limit and higher than the upper limit of the present invention. However, in the latter case, the alloy plate is cracked, which causes problems in screen quality and press molding quality, respectively.

Material No. 24 and No. 25 are cold rolling (CR
₍₂ ,%) exceeds the upper limit of the present invention and is less than the lower limit, and in both cases, the mixed particle size exceeds the value of the present invention, uneven transmission occurs, and there is a problem in press molding quality. is there.

Material No. 26 and Material No. 27
Indicates that the finish cold rolling rate (CR ₃ ,%) exceeds the upper limit of the present invention and is less than the lower limit. In the former case, the average particle size is less than the lower limit of the present invention, there is a problem in shape fixability, and cracks in the alloy plate occur. In the latter case, the mixed particle size exceeds the upper limit specified in the present invention, and uneven transmission occurs. Furthermore, the degree of integration of {211} crystal planes exceeds the upper limit specified in the present invention, the alloy plate is cracked, and {21}
The degree of integration of the 0} crystal plane also exceeds the upper limit specified in the present invention, and a partial color shift occurs.

Material No. 28, No. 29, No. 30
Are those whose temperature during annealing before pressing exceeds the upper limit,
Time t exceeds the upper limit, T <-123log t + 93
7 In Material No. 28, the mixed particle size exceeded the upper limit specified in the present invention, uneven transmission occurred, and {21
1} The degree of integration of crystal planes also exceeds the upper limit specified in the present invention, and the alloy plate is cracked. In No. 29, the degree of integration of {211} crystal planes exceeded the upper limit specified in the present invention, and the alloy plate was cracked. Further, the degree of integration of the {331} crystal plane also exceeds the upper limit specified in the present invention, and a partial color shift occurs. Further, the material No. 30 has an average particle size smaller than the regulation of the present invention and has a problem in shape fixability.
The degree of integration of crystal planes exceeds the upper limit specified in the present invention, and the alloy plate is cracked.

As described above, even in the case of the component composition within the range of the present invention, the hot rolled sheet annealing condition, the cold rolling condition, the finish cold rolling rate and the pre-press annealing condition should be within the present invention range. Thus, it is understood that the press molding quality and screen quality intended by the present invention can be obtained.

Further, the above-mentioned material No. 4 in the embodiment,
As can be seen from No. 40 and No. 43, Fe-Ni alloy thin plate and Fe-Ni-Co alloy thin plate which have the required press-forming quality which is a feature of the present invention and which does not cause partial color misregistration. It is understood that the flat mask obtained even after etching had no unevenness and the required etching property was obtained.

As is clear from Examples 1 to 2, when the degree of integration of {211} crystal faces exceeds 20% and / or the average crystal grain size is outside the range of the present invention, before pressing. When the elongation after annealing, the n value, and the r value are lower than those of the examples of the present invention and the degree of integration of {211} crystal faces is high and / or when the average grain size is out of a specific range, these specific values are It is presumed that the temperature will decrease and cracks will occur during press molding.

[0083]

According to the present invention as described in detail above,
Excellent press moldability, that is, excellent shape fixability during molding and good compatibility with molds, suppression of material cracking, suppression of transmission unevenness, and further suppression of partial color misregistration. For shadow masks that can give excellent screen quality
Since it is possible to provide an Fe-Ni alloy thin plate or an Fe-Ni-Co alloy thin plate and a method for producing the same, it is an invention that brings industrially advantageous effects and is highly effective.

Further, according to the present invention as described above, the required etching quality and press molding quality can be obtained even when annealing before press molding is performed before etching. Since it is possible to provide an Fe-Ni alloy thin plate and a Fe-Ni-Co alloy thin plate for a shadow mask that can be omitted, an industrially advantageous effect is brought about, and it is a large invention. is there.

[Brief description of drawings]

FIG. 1 is a table showing the relationship between the occurrence of cracks during press forming, the degree of accumulation of {211} crystal faces, and the average austenite grain size after pre-press annealing.

FIG. 2 is a chart summarizing the relationship between the occurrence frequency of transmission unevenness after press forming and the mixed grain size of austenite crystal grains after annealing before press forming.

FIG. 3 is a chart showing the relationship between the mixed grain size of austenite grains after pre-press annealing and the cold rolling rate (CR ₂ ).

FIG. 4 is a chart showing the relationship between the mixed grain size of austenite crystal grains after annealing before pressing and the cold rolling rate (CR ₁ , CR ₂ ), in which the mixed grain size of austenite crystal grains is shown in parentheses. .

FIG. 5: Average austenite crystal grain size after pre-press annealing, mixed grain size of austenite crystal grains, {331}, {2
9 is a chart summarizing the relationship between the degree of integration of 10} and {211} crystal faces and the pre-press annealing conditions.

Claims (5)

[Claims] 1. Wt%, Ni: 34-38%, Si: 0.0
7% or less, B: 0.0005% or less, O: 0.0020%
Hereinafter, N: 0.0019% or less is contained, and the balance is Fe and inevitable impurities. The average austenite crystal grain size D of the alloy sheet before annealing is 15 to 45 μm before annealing. An Fe-Ni alloy thin plate for a shadow mask excellent in press formability, which is below and has a crystal plane integration degree on the surface of the alloy plate satisfying the values in the following table. (However, D is the average grain size of austenite in the alloy plate. D _max is the maximum grain size of austenite in the alloy plate. 2. In wt%, Ni: 34-38%, Si: 0.0
7% or less, B: 0.0005% or less, O: 0.0020%
Below, N: 0.0019% or less, Co: 1.0% or less is contained, and the balance is composed of Fe and inevitable impurities. Further, the average austenite grain size D of the alloy sheet before annealing before press molding is 15-45 μm An Fe-Ni-Co alloy thin plate for a shadow mask excellent in press formability, which is below and the degree of crystal plane integration on the surface of the alloy plate satisfies the values in the following table. (However, D is the average grain size of austenite in the alloy plate. D _max is
Maximum grain size of austenite in alloy plate. [Table 2] 3. In wt%, Ni: 30-38%, Si: 0.0
7% or less, B: 0.0005% or less, O: 0.0020%
Hereafter, N: 0.0019% or less, Co: 1.0% to 6%, and the balance Fe and unavoidable impurities, and the average austenite crystal grains of the alloy sheet before annealing before press forming. Diameter D is 15 ~ 45μm, An Fe-Ni-Co alloy thin plate for a shadow mask excellent in press formability, which is below and the degree of crystal plane integration on the surface of the alloy plate satisfies the values in the following table. (However, D is the average grain size of austenite in the alloy plate. D _max is
Maximum grain size of austenite in alloy plate. [Table 3] 4. A hot-rolled steel strip of a low thermal expansion alloy having the components according to claims 1 to 3 is subjected to hot-rolled sheet annealing, followed by cold rolling (CR ₂ ) and subsequent recrystallization annealing. After manufacturing, in the process of performing stress relief annealing after finish cold rolling (CR ₃ ), the hot rolling plate annealing is performed at 810 ° C to 890 ° C.
The rolling reduction (CR ₂ %) in cold rolling is 81 to 94
%, Reduction ratio (CR ₃ %) in finish cold rolling is 16 to 29%
The annealing before press forming is performed at a temperature (T ° C) of 740 to 900 ° C and a time (tmin) of
The average austenite crystal grain size of the alloy plate after annealing, the mixed grain size of the austenite crystal grains, and the degree of integration of crystal planes on the surface of the alloy plate are claimed under the conditions of 2 to 40 min and T ≧ -123 log t + 937. The Fe-Ni alloy thin plate for a shadow mask and the Fe-Ni-Co alloy thin plate having excellent press formability, characterized by satisfying the above value. 5. A hot-rolled steel strip of a low thermal expansion alloy having the components according to claim 1 to 3 is annealed after hot-rolled sheet annealing.
Next cold rolling (CR ₁ ) and subsequent recrystallization annealing, then secondary cold rolling (CR ₂ ) and recrystallization annealing, then finish cold rolling (CR ₃ ), and later strain relief At the time of manufacturing in the annealing process, the hot-rolled sheet annealing is performed at 810 to 890 ° C., and the reduction ratio (CR ₁ %) in the primary cold rolling is 40 to 55.
%, The reduction ratio (CR ₂ %) at the reduction ratio in the secondary cold rolling is 8
1 to 94%, the reduction ratio (CR ₃ %) in finish cold rolling is 1
Each of the annealing is performed within a range of 6 to 29%, and the subsequent annealing before press forming has a temperature (T ° C) of 740 to 900 ° C, a time (Tmin) of 2 to 40 min, and T ≧ -123 log t +.
Provided that the average austenite crystal grain size of the alloy plate after annealing, the mixed grain size of the austenite crystal grains, and the degree of integration of crystal planes on the surface of the alloy plate satisfy the value of claim 1 under the condition of satisfying 937. Fe-Ni alloy thin plate for shadow masks and Fe-Ni with excellent press formability
─ Method for manufacturing Co alloy sheet.