KR100375191B1 - Fe-Ni based alloy for semi tension mask, plate thereof and semi tension mask and color braun tube using said alloy - Google Patents

Abstract

When a creep phenomenon occurs, the mask is stretched to mitigate most of the weighting, causing various problems such as wrinkles and deterioration of vibration characteristics. In particular, when the blackening treatment is performed at high temperature to improve the magnetic characteristics, the creep rate increases.

Ni is 34% by mass (%) (hereinafter referred to as%) or more and 45% or less, Mn is 0.01% or more and 0.5% or less, and 0.01, or more, in total of one or two or more of Cu, Nb, Mo, W, and Ta. A Fe-Ni-based alloy for a semi-tension mask, containing 1.5% or less, and having excellent creep characteristics, consisting of residual Fe and unavoidable impurities.

Description

Fe-Ni based alloy and alloy plate for semi-tension mask and semi-tension mask and color braun tube using same {Fe-Ni based alloy for semi tension mask, plate Y and semi tension mask and color braun tube using said alloy}

The present invention relates to a semi-stretched tension mask (SST mask, briefly referred to as a semi-tension mask) made of a Fe-Ni-based alloy used in a cathode ray tube (brown tube). The present invention relates to a material having excellent creep characteristics and excellent in suppressing wrinkle generation of a mask after baking after applying tension, a semi-tension mask using the material, and a color brown tube using the semi-tension mask.

The mask of CRT is formed by forming the mask material by dot or slot for electron beam transmission by etching, and then press-molding in the form of a mask, and by forming a long slit for electron beam transmission on the mask material by etching. After that, it is divided into a plurality of aperture grilles that stretch upward and downward to impart the best shape to the frame.

In the shadow mask method, Fe-36% Ni (Invar alloy) is generally used to improve the dope characteristics caused by thermal expansion. On the other hand, in the aperture grill system, the ducting due to thermal expansion is less likely to occur due to its structural characteristics, and even inexpensive mild steel is used even if the thermal expansion coefficient is high.

Each method has one piece and both methods are used in the market. Recently, semi-stretched, tension masks (semi-tension masks) which take advantage of the two methods are newly considered.

This method is a method in which a dot or slot for electron beam transmission is stretched up and down in the same manner as the aperture grill method without pressing a mask material formed by etching, and supported by a frame (most method). At the beginning of the development of this new method, the mask material was stretched in four directions not only up and down, but also from side to side. However, when the mask material is stretched in four directions, the mask is sometimes torn. In order to avoid the risk of tearing such a mask, a test was made in which the mask material was pulled in only two directions to obtain good results. The mask produced by this improvement was called semi-stretched tension mask (abbreviated semi-tension mask) by the meaning employ | adopted by "stretching with weak force in an up-down direction" rather than the tension in four directions.

1A and 1B are explanatory diagrams schematically illustrating a semi-tension mask and an aperture grill mask. Both types of masks are stretched up and down. In the semi-tension mask, a plurality of vertical slot rows are formed in the whole width, and each slot row is composed of a plurality of slots with a bridge between adjacent slots, while an aperture grille mask has a plurality of long widths in the full width. It includes a vertical slit and requires a damper wire to suppress the vibration of the mask from a sound source such as a speaker. A bridge in a semi-tension mask is an unetched portion between slots in each slot row when forming a slot by etching. The bridge serves to prevent twisting of the vertical slot rows. The semi-tension mask is also called a tension mask with a bridge because a bridge exists in each slot row.

Compared to the shadow mask method by the press, the SST method can be made more flat, and also high brightness and high resolution can be achieved. In addition, vibration characteristics are superior to the aperture grill method, and a damper wire is not required, and the load to be pulled up and down can be lowered, contributing to cost reduction.

On the other hand, in the semi-tension mask method, unlike the aperture grill method, the dominant phenomenon due to thermal expansion occurs due to the lowest strength, the presence of a bridge, and the like. Therefore, Fe-Ni based on the Invar alloy having a low thermal expansion coefficient is mainly used. Adoption of a system alloy is considered. However, when the Invar alloy used in the conventional press method was used, it was found that the heat treatment in the mask assembly step caused tension down, causing a large problem such as wrinkles.

As mentioned above, it was found that the conventional Invar alloy was unsuitable for the semi-tension mask method, and the cause was examined in detail at each stage of the mask production, and it was found that it was related to the creep characteristics of the material.

In other words, the material etched in the shape of dots or slots is subjected to a blackening treatment, and then welded to the frame member so as to apply a constant load, but thereafter, deformation caused by welding or the like is removed by baking. At this time, it was found that the Invar alloy tensioned with the frame member exhibits plastic deformation at high temperature, that is, creep phenomenon. When creep occurs, the mask is stretched to reduce the tension (tension down), causing various problems such as wrinkles and deterioration of vibration characteristics.

1A and 1B are explanatory views schematically illustrating a semi-tension mask and an aperture grill mask.

That is, the present invention solves the above problems,

(1) The Ni content is 34% or more and 45% or less, Mn is 0.01% or more and 0.5% or less, and one or two or more of Cu, Nb, Mo, W, and Ta is 0.01% or more and 1.5% or less in total. An Fe-Ni-based alloy for a semi-tension mask, which has excellent creep characteristics, which is composed of Fe and unavoidable impurities.

(2) The Fe-Ni-based alloy for semitension mask according to (1), which contains Si at 0.005% or more and 0.20% or less and Al at 0.005% or more and 0.030% or less.

(3) The Fe-Ni-based alloy for semitension mask according to (1) to (2), wherein C is 0.010% or less, P is 0.015% or less, and S is 0.010% or less among unavoidable impurities.

(4) In the sheet material manufactured by hot-rolling and cold-rolling the alloy of the above-mentioned (1) to (3), the semi-tension mask for which the final cold rolling has a workability of 15% or more and 60% or less. Fe-Ni-based alloy sheet.

(5) A sheet material produced by hot rolling or cold rolling by melting the alloy of the above (1) to (3), wherein the tensile strength after the final cold rolling is 600 N / mm 2 or more and 700 N / mm 2 or less. Fe-Ni alloy sheet material for semi tension mask.

(6) A sheet material produced by hot rolling or cold rolling by melting the alloy of the above-mentioned (1) to (3), wherein 0.2% yield strength after final cold rolling is 570 N / mm 2 or more and 670 N / mm 2 or less. Fe-Ni alloy for semi-tension masks.

(7) A sheet material produced by hot rolling or cold rolling by melting the alloy of (1) to (3), wherein the strain removal annealing is performed after the final cold rolling. -Ni based alloy.

(8) A semi-tension mask using Fe-Ni-based alloys and alloy plate materials described in the above (1) to (7).

(9) A color-brown tube, characterized in that the semi-tension mask according to (8) is used.

In the semi-tension mask method, blackening is generally performed after the blackening treatment. If the blackening treatment temperature is much lower than the recrystallization temperature of the Fe-Ni-based alloy, as described in the patent application (Japanese Patent Application No. Hei 10-356219), the work hardening of this alloy can be used to improve the creep characteristics. Can be. However, when the blackening temperature, heat treatment called baking, etc. become more difficult, the improvement effect of the creep characteristic by work hardening is not as much as expected.

Here, the best effect expected by increasing the blackening treatment temperature is the improvement of the magnetic characteristics. For example, in the case of an Invar alloy for press molding shadow masks, the maximum specific permeability of 870 to 1000 when blackening at 590 ° C. is blackened at 640 ° C., which is 50 ° C., to a maximum specific permeability of 1030 to 1200. In addition, in the geomagnetic shield after an alternating current element like a CRT tube, the greater the maximum specific permeability, the better the shielding property.

That is, the present invention, by selecting the type and amount of elements added to the Fe-Ni-based alloy, there is almost no increase in the coefficient of thermal expansion, without generating precipitates that hinder etching, thereby producing a more excellent work hardening effect, The present invention relates to an invention that can reduce the creep speed. In the present Fe-Ni alloy, the present invention exhibits a particularly remarkable effect when heat treatment such as blackening treatment is performed at a temperature at which softening starts.

In addition, the addition of the trace element is excellent in the mechanical properties in the case where the final workability is small, and it is difficult to soften even if the final workability is large. Since the semi-tension mask is generally blackened before disguising, the final stress rolling may be caused by non-uniformity of residual stress when etched in a dot or slot shape, and may deform when it is opened by blackening. It is preferable to prevent this by performing strain removal annealing later.

In other words, the present inventors added one kind or two or more kinds of Cu, Nb, Mo, W, and Ta to the Fe-Ni-based alloy, and made Al and Si into an appropriate amount, By carrying out strain removal annealing as needed, it was found that creep characteristics can be significantly improved without wrinkles or the like in each step of blackening, disinfection, and baking.

Next, the reason for limitation of this invention is described.

Ni: The content of Ni affects the thermal expansion and softening characteristics. When Ni exceeds 36%, the coefficient of thermal expansion becomes large, which is disadvantageous in terms of cost. However, since the softening temperature rises and creep elongation in baking becomes small, the maximum force of the semi-tension mask can be increased, and deterioration of the doming characteristic due to thermal expansion can be prevented. In addition, the more Ni, the better the magnetic characteristics, which is advantageous in terms of the magnetic shield. However, when Ni exceeds 45%, the difference with the mild steel in the thermal expansion characteristics is small, and in view of cost, there is no advantage of using the Fe-Ni-based alloy in the semi-tension mask. Therefore, the upper limit of Ni is made into 45%. Further, even if Ni is smaller than 36%, the coefficient of thermal expansion is large. However, when Ni is low, the softening temperature is lowered, so creep elongation in baking tends to be large, and deterioration of the doming characteristic due to thermal expansion cannot be prevented by the most force of the semi-tension mask. Therefore, the lower limit of Ni is made into 34%. In order to increase the maximum force with the semi-tension mask, the frame is required to have high strength and the cost is increased. Therefore, the total component range of Ni is preferably 34% or more and 38% or less from the thermal expansion characteristics and cost.

Mn: Mn is necessary to detoxify S contained as an impurity that inhibits hot workability. And when Mn is less than 0.01%, this effect will be ineffective. When it exceeds 0.5%, etching property will be inhibited and a thermal expansion coefficient will become large. Therefore, although the component range is made into 0.01% or more and 0.5% or less, the preferable range for making etching property and thermal expansion characteristics better is 0.01% or more and 0.1% or less.

Si: Si is added as a deoxidizer, but when Si is more than 0.2%, the etching property is greatly inhibited, so it is preferable to be 0.20% or less. However, the component range of the lower limit is made 0.005% or more because of its small and effective effect of improving creep characteristics. However, in order to improve etching property, the preferable range is 0.005% or more and 0.03% or less.

Al: Al is used as a deoxidizer, and when Al is used in an amount of more than 0.005%, the creep property is improved. However, when the Al content is more than 0.03%, alumina is formed, the etching property is inhibited, and surface scratches caused by alumina in cold rolling are generated. Therefore, the component range is made into 0.005% or more and 0.030% or less.

C: C forms carbide, but when C exceeds 0.010%, carbides are excessively produced, which inhibits etching property. Therefore, while C is made 0.01% or less, since solid solution C also adversely affects etching property, C should be as few as possible, and the more preferable range of C is 0.005% or less.

P: Excessive P content causes etching failure. Therefore, it is necessary to make content into 0.015% or less.

S: When S exceeds 0.010%, hot workability is inhibited and sulfide-based inclusions increase, which adversely affects the etching property. Therefore, an upper limit is made into 0.010% or less.

Cu, Nb, Mo, W, Ta: By adding Cu, Nb, Mo, W, Ta, creep characteristics can be improved. However, if the total amount is less than 0.01%, the creep improvement effect is small.

In addition, the more the addition amount, the better the creep characteristic, but the coefficient of thermal expansion becomes larger, and in particular, increasing the addition amount of Nb, Mo, W, and Ta may increase the cost. However, since the softening temperature is increased by adding Cu, Nb, Mo, W and Ta, deterioration of the doming characteristic due to thermal expansion can be prevented by increasing the maximum force of the semi-tension mask as in the case of increasing Ni. However, if it adds more than 1.5%, since cost will increase much, the component range of these elements shall be 0.01% or more and 1.5% or less in 1 type, or 2 or more types in total.

Final cold rolling: If the final cold rolling is less than 15%, the amount of hardening is small and creep improvement is not so remarkable. In addition, when the workability exceeds 60%, softening starts at the time of blackening treatment, and rather, high temperature strength and creep characteristics are deteriorated. Therefore, the final cold rolling workability is 15% or more and 60% or less. In the case where the blackening treatment temperature exceeds 600 ° C, the workability of the final cold rolling is preferably 20% or more and 40% or less.

Deformation annealing: Deformation annealing does not affect creep elongation after blackening, but is preferably carried out to suppress uneven deformation caused by opening of residual stress during blackening.

Tensile strength after final cold rolling: In the material for a semi-tension mask, it is preferable that the mask strength at the time of applying tension and the high temperature strength and creep strength of the mask at the time of baking heat treatment have high design margin. It was found that the mechanical properties of these masks can be defined by the material strength after final cold rolling. When the tensile strength after the final cold rolling is less than 600 N / mm 2, the setting of the range in which the load that can be best imposed on the mask becomes very difficult, so the lower limit is set to 600 N / mm 2. Moreover, when it exceeds 700 N / mm <2>, softening start temperature will begin to fall. Therefore, the range of tensile strength after final cold rolling shall be 600 N / mm 2 or more and 700 N / mm 2 or less.

0.2% yield strength after final cold rolling: When the 0.2% yield strength after final cold rolling exceeds 670 N / mm 2, the softening start temperature is lowered as the tensile strength exceeds 700 N / mm 2. In addition, if it is less than 570 N / mm 2, since the difference from the tensile stress to be simulated is small, creep phenomenon occurs and problems such as wrinkle generation and vibration characteristic deterioration occur. Therefore, the range of 0.2% yield strength after final cold rolling shall be 570 N / mm <2> or more and 670 N / mm <2>.

(Example)

The present invention will be described in detail below.

Table 1 shows the alloy composition used in the examples of the present invention.

After the Fe-Ni-based alloy having the components shown in Table 1 was melted in a vacuum melting furnace to 3 mm thick by forging and hot rolling, cold rolling and bright annealing were repeatedly performed, and about 0.3 mm to about 0.11. It was processed into a cold rolled material having a thickness of mm.

Furthermore, after recrystallization annealing of these materials, they were cold rolled to a thickness of 0.1 mm to prepare materials having various changes in final workability. They were measured at room temperature for tensile strength and 0.2% yield strength, blackened at 605 ° C. and 640 ° C. for 15 minutes, and then loaded with 100 N / mm 2 or 200 N / mm 2 tensile stress while heating to 460 ° C. , Creep height was measured after 1 hour. At this time, the tensile direction was made into the rolling parallel direction.

In addition, the material having a chemical composition of A to Y in Table 1, the final cold rolling degree of about 35%, while measuring the average coefficient of thermal expansion between 30 ℃ and 100 ℃, at the surface of 60 ℃ Aqueous ferric chloride solution was sprayed at a pressure of 0.3 MPa to observe the state of the etching surface.

Table 2 shows the state of the etching surface as a result of tensile strength, 0.2% yield strength, creep elongation, and etching property.

Nos. 1 to 14 are examples of the invention that satisfy claims 1 to 6.

In the real blackened mask, the crease elongation was measured by blackening the wrinkled and non-occurring materials after baking for 15 minutes at 640 ° C and applying a stress of 200 N / mm 2 at 460 ° C for 1 hour. The creep elongation at which wrinkles occurred was 0.16%. Nos. 1 to 14 have a creep extension of less than 0.16% even when the blackening treatment temperature is high at 640 ° C. and the tensile stress is large. Among them, from No. 8 and No. 9, when there are many additive elements (Mo), even if the final cold rolling process is large, creep elongation after blackening treatment at 640 ° C. is lower than the final cold rolling process No. 9. It turns out that it becomes small even compared with that of No.8. This indicates that the creep elongation does not increase even when the blackening treatment temperature is increased because the softening temperature has moved to the high temperature side when there are many additive elements.

In addition, since No.15 and No.17 have a final cold rolling workability of less than 15%, the strength after the final cold rolling is low, which is not preferable for handling such as etching. Further, in No. 16 and No 18, since the final cold rolling workability exceeded 60%, the softening start temperature was lowered. As a result, the creep elongation at the time of loading 200 N / mm 2 was large, especially 640 ° C. blackening. The creep elongation after treatment exceeds 0.16% estimated by the minimum which wrinkles generate | occur | produce with a semi tension mask. In No. 16 and No. 18, since the creep extension is small in No. 18 to which Nb is added, the softening start temperature is shifted to the high temperature side by the added elements (Cu, Nb, Mo, W, Ta). You can get a glimpse.

No. 19 and No. 20 do not contain the additive elements (Cu, Nb, Mo, W, Ta) in an amount defined in claim 1 of the present invention, and therefore at 600 ° C regardless of the final cold rolling process. Even in the case of blackening, the creep elongation exceeds 0.16% when a stress of 200 N / mm 2 is loaded.

No. 21, No. 25, and No32 have a large coefficient of thermal expansion because the chemical component (Nb or Ni) is out of the range defined in claim 1 of the present invention, and is unsuitable as a material for a semi-tension mask from the viewpoint of the doming characteristic. Do. In addition, although the added elements of Cu, Nb, Mo, W, Ta exceeded the claims of the present invention as an example, they are compared only in Nb, but the Cu, Mo, W, Ta also increased when the content increased. It is clear from the result of Table 2, and when it exceeds a claim, it becomes unsuitable as a material for a semi-tension mask.

In addition, No. 22 to No. 24 and No. 26 to No. 28, No. 22 is Si, No. 23 is Al, No. 24 is Mn, No. 26 is C, No. 27 Silver P, No.28 S exceeds the specified amount. These creep elongations are not a problem for wrinkle generation of the semi-tension mask at 0.16% or less, but foreign matters contained in a large amount in the material (SiO ₂ in No. 22, Al ₂ O ₃ in No. 23, No. 24 in inclusions, etc.). And MnS in No. 28, iron carbide in No. 26, and flakes in No. 27) are etched when they are etched to roughen the etching surface, and thus, they are not sufficient as a material for semitension masks. Particularly, since Al ₂ O ₃ is present in the form of a cluster, and MnS or phosphate is ductile and elongated in a linear shape, they deteriorate the shape of the edge of the dot- or slot-shaped etching hole. In addition, in No. 24, Mn increases the coefficient of thermal expansion.

In addition, since No. 29 is less than 0.005% of Si, the creep elongation after the blackening treatment is larger than that of Nos. 1 to 14 in the present invention, and blackening is performed at 640 ° C. to load a 200 N / mm 2 stress. Because the temperature is close to 0.16%, which is estimated as the lower limit of the occurrence of wrinkles in the semi-tension mask to be impersonated, the higher temperature of blackening treatment temperature higher than this is not preferable. No. 31 has the same phenomenon because Al is less than 0.005%.

Since No. 30 has a creep extension of 0.16% or less and a small coefficient of thermal expansion, but Mn is less than 0.01%, it cannot be harmed by S segregation during hot working. Cracking or peeling may occur. In the case of etching, the unevenness of the grain boundary is large, which is considered to be due to segregation of S into the grain boundary.

In addition, although the strain removal annealing is not performed after the final cold rolling in the Example of this invention, even if the test piece is produced on the same conditions as No.4, and the strain removal annealing is performed at 700 degreeC for 1 second, it will be blackened 640 degreeC. It is confirmed that the creep elongation at the time of 200 N / mm 2 load after treatment is not affected by 0.128%. However, if the deformation removal is not carried out, the balance of the residual stress distribution may be broken when the mask is processed into a dot or slot mask by etching, which may be released by blackening and deteriorate the shape. It is preferable to perform deformation removal annealing so that the shape does not change by blackening. In addition, although shape correction by a tension leveler etc. may be performed as needed, the validity of this patent does not have a problem even if these processes enter naturally, it goes without saying that it is contained in the scope of this claim.

Since the Fe-Ni alloy of the present invention has excellent creep characteristics and low thermal expansion coefficient, it is preferable as a material for color brown tube without color shift. It is especially effective when the blackening treatment is performed at high temperature (above 600 ° C) to improve magnetic shielding properties.

Moreover, the semi tension mask which consists of this invention is suitable for enabling the flattening of the screen of a color-brown tube.

Claims (9)

Ni is 34% by mass (%) (hereinafter referred to as%) or more and 45% or less, Mn is 0.01% or more and 0.5% or less, and one or two or more of Cu, Nb, Mo, W, and Ta is 0.01% or more in total. A Fe-Ni-based alloy for a semi-tension mask containing 1.5% or less, and having excellent creep characteristics, which is composed of residual Fe and unavoidable impurities. The Fe-Ni-based alloy for semi-tension mask according to claim 1, wherein Si is 0.005% or more and 0.20% or less and Al is 0.005% or more and 0.030% or less. The Fe-Ni-based alloy for semitension mask according to claim 1 or 2, wherein C is 0.010% or less, P is 0.015% or less, and S is 0.010% or less among the unavoidable impurities. The sheet material manufactured by hot-rolling and cold-rolling the alloy of the base material of Claim 1 or 2 WHEREIN: The workability of final cold rolling is 15% or more and 60% or less, The semi tension mask for Fe-Ni-based alloy sheet. A sheet material produced by hot rolling or cold rolling by melting the alloy according to claim 1 or 2, wherein the tensile strength after final cold rolling is 600 N / mm 2 or more and 700 N / mm 2 or less. Fe-Ni-based alloy sheet for masks. The sheet | seat material manufactured by hot-rolling and cold-rolling which melt | dissolves the alloy of Claim 1 or 2, The 0.2% yield strength after final cold rolling is 570 N / mm <2> or more and 670 N / mm <2> or less Fe-Ni-based alloy sheet for tension mask. The sheet material manufactured by hot-rolling or cold-rolling the alloy of the base material of Claim 1 or 2, The strain removal annealing is performed after final cold rolling, The Fe-Ni-type alloy for semi tension masks characterized by the above-mentioned. Plate. A semi-tension mask comprising the Fe-Ni-based alloy according to claim 1 or 2. The color-brown tube which uses the semi tension mask of Claim 8.