JPH0798982B2 - Manufacturing method of in-pipe parts - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an in-tube component capable of producing an in-tube component such as a shadow mask, a frame, an inner shield, and a bimetal used for a color picture tube with good moldability and a method for producing the same. Regarding

[Technical background of the invention and its problems]

So-called in-tube parts such as shadow masks, frames, inner shields, bimetals, and electron guns of color picture tubes have better etching and moldability than before, and an oxide film that contributes to reducing electron beam reflection is formed on the surface. It is made of rimmed steel, Al-killed steel, etc. However, in order to deal with various new media in recent years, high quality of the color picture tube, that is, so-called easy-to-see and extremely fine display image is required, and the shadow mask composed of the above-mentioned rimmed steel or Al killed steel, Problems have arisen in using frames, inner shields, bimetals, and the like.

That is, when the color picture tube is operating, the temperature of each member is
The temperature rises to 30 to 100 ° C., and so-called doming occurs due to distortion in the molded shape of the shadow mask due to its thermal expansion. As a result, the relative positional relationship between the shadow mask and the fluorescent screen is deviated, and the purity drift (P
A color shift called D) occurs. Especially in a high-quality color picture tube, since the aperture diameter and the aperture pitch of the shadow mask are very small, the relative deviation amount becomes large, and the inside of the tube made of the rimmed steel or Al-killed steel described above becomes large. Parts cannot be used practically.

Therefore, conventionally, as a material for forming this kind of in-pipe component,
Ni-Fe alloys with a low coefficient of thermal expansion, such as amber (36Ni-
Fe) can be used, for example, in Japanese Examined Patent Publication No.
50-58977, JP-A-50-68650 and the like. However, this type of Ni-Fe alloy has poor thermal conductivity,
Not only heat is easily stored, but also a recess from the normal shadow mask spherical surface to the electron gun side, that is, so-called springback is likely to occur.

That is, the springback has a correlation with the 0.2% proof stress value of the material, for example, as shown in FIG. The lower the 0.2% proof stress value, the smaller the springback and the better the moldability. Conversely, above
If the 0.2% proof stress is 20 kg / mm ² or more, the forming becomes extremely difficult.

Therefore, in order to lower the 0.2% proof stress of the above materials,
It has been attempted to vacuum anneal at a temperature of ℃ or more, or to form a pipe part in a range of 100 to 200 ℃. But,
In any case, it is the actual situation that the rimmed steel, Al steel and the like do not reach the etching property and formability.

On the other hand, regarding the material (in-tube component) after the above-mentioned molding process is completed, it is desired that the material is not deformed by handling or howling is caused by a speaker or the like. Therefore, it is desired that the 0.2% proof stress of the material after molding and its elastic modulus are sufficiently high. In other words, it is desirable that the in-tube component be soft before the molding process and hard after the molding process.

[Object of the Invention]

The present invention has been made in consideration of such circumstances, the purpose is to have a lower coefficient of thermal expansion than rimmed steel and Al steel, and also have good formability close to each of these steels,
Moreover, it is an object of the present invention to provide an in-tube component having a good howling prevention effect and a good deformation prevention effect after the molding process, and a manufacturing method thereof.

[Outline of Invention]

The present invention is 25 to 45 wt% Ni, 0.3 to 10 wt% total of at least one of Cr and Mn, Ti, Nb, Al, Mo, V, W, Zr, at least one element selected from Ta. 2.5wt in total amount consisting of
% Or less of the precipitation hardening component, the balance Fe and unavoidable impurities alloy material is annealed at 700 ~ 1300 ℃ to reduce the yield strength of the alloy material, then the alloy material is processed, 500 ~ 800 ℃ This is a method of manufacturing a pipe part made by blackening. Then, by adding Cr or Mn, the forming process after the annealing process is facilitated, and by the blackening process after the forming process (which also serves as an aging process), the precipitation hardening component is deposited to form the inside of the formed pipe. The parts are hardened, and further, the heat emissivity of the parts in the tube obtained by manufacturing in this way is enhanced.

Here, the reason why the composition amount of Ni is 25 to 45 wt% is that the coefficient of thermal expansion thereof is 90 × 10 ⁻⁷ / ° C. or less, and if the addition amount of Ni is outside the above range, the present invention is It is not possible to obtain the intended in-tube component having a low coefficient of thermal expansion. Furthermore, the amount of Ni added
If it exceeds 45% by weight, the 0.2% proof stress increases, and the formability thereof deteriorates significantly. At the same time, the improvement of the oxidation resistance makes it extremely difficult to form a blackened film on the surface.

Regarding the etching property, if the amount of Ni becomes large, it becomes difficult to perform fine etching, the inner wall of the etching hole becomes a so-called dry hole, and a large amount of Ni dissolved in the etching solution causes a decrease in the etching rate. Problem arises.

Cr or Mn generally increases the coefficient of thermal expansion of the Fe-Ni alloy, but on the other hand decreases the 0.2% proof stress,
It greatly contributes to the improvement of the moldability. That is, the Cr plays an important role in the annealing process of the in-pipe component after etching the in-pipe component material to obtain a flat mask having many holes.

That is, generally, Cr or Mn is added to a 36Ni-Fe alloy, and when not annealed at a recrystallization temperature or higher, the crystal grains are fine, which causes an increase in 0.2% proof stress at room temperature, for example, a curvature as a shadow mask. It will be difficult to keep. Therefore,
The addition of Cr or Mn only enhances the strength of the material. However, when the specific annealing treatment is applied to the 36Ni-Fe alloy containing Cr or Mn as in the present invention,
The 0.2% proof stress reduction amount is 36Ni- with no addition of Cr or Mn.
Remarkably large compared with Fe alloy. That is, Cr or Mn contained in the material has an important effect in greatly reducing the 0.2% proof stress of the material in the annealing process.

By the way, if the added amount of Cr or Mn is less than 0.3 wt%, the 0.2% proof stress of 24Kg / mm can be obtained even if the annealing temperature is increased to 1200 ° C, just like the 36Ni-Fe alloy without added Cr or Mn. It cannot be less than ² . If the amount added exceeds 10 wt%, the coefficient of thermal expansion becomes 90 × 10 ⁻⁷ / ° C. or more, which causes color misregistration, and is unsuitable for use in a high definition color picture tube. Also, if the amount of Cr or Mn added exceeds 10 wt%, a protective film of Cr ₂ O ₃ (Mn ₃ O ₄ ) is likely to be formed on the surface, leading to a decrease in the surface blackening rate and other blackening treatments. It causes inconvenience. The amount of Cr or Mn added is 1 to 1 in consideration of low expansion property, etching property, and low chromium content in the waste liquid.
4wt% is desirable. Further, even if the above Cr and Mn are added in combination, these characteristics do not deteriorate.

FIG. 2 (a) shows a material for pipe parts according to the present invention, Mn.
A change in the coefficient of thermal expansion of the in-tube component made of a 36Ni-Fe alloy added with is shown as a characteristic A, and a characteristic B is a change in its 0.2% proof stress. The second
Figure (b) shows the above Cr in 36Ni-Fe alloy with Cr added.
The change in the coefficient of thermal expansion with respect to the addition amount of is shown as the characteristic D, and the characteristic C is the change in the 0.2% proof stress. However,
These characteristics are the measurement results of the in-pipe parts that were annealed at 900 ° C for 1 hour. As shown in these figures, addition of up to 5 wt% Cr or Mn
It can be seen that the 0.2% proof stress is significantly reduced, and as a result, its formability is improved.

In addition, the addition of Cr or Mn is 30-35% Ni and up to 7%
It is also effective for Super Amber containing Co.

Next, the characteristics of the in-pipe component due to the addition of the precipitation hardening component element will be described.

The upper limit of the addition amount of the precipitation hardening component element is set to 2.5 wt%, because the addition of more than that causes the deformation of the parts in the pipe during the aging treatment that also serves as the blackening treatment and also serves as the solution treatment. This is to prevent unintentional hardening of the pipe parts during the annealing process.

Specifically, Ti, which is a precipitation hardening component element, precipitates by aging treatment and improves the strength of the alloy, but if its addition amount is less than 0.05 wt%, it does not exhibit a sufficient hardening action, that is, the strength of the alloy is Not high enough. The addition amount is 2.0wt
If it exceeds%, the moldability will deteriorate. Therefore, preferably 0.
It is preferable to add the above Ti in the range of 2 to 1.0 wt%.

Al, which is a precipitation hardening component element, is an element that is precipitated by aging treatment as in the case of Ti and is useful for improving the strength of the alloy. However, if the amount added is less than 0.05 wt%, the alloy will not exhibit a sufficient hardening effect, that is, the strength of the alloy will not be sufficiently high. Further, if the addition amount exceeds 1.5 wt%, the moldability becomes poor.

Further, Zr, which is a precipitation hardening component element, contributes greatly to the improvement of strength by the combined addition of Ti and Al described above. still,
Needless to say, the addition thereof alone is also useful for improving the strength of the alloy. However, the addition amount is 0.05
If it is less than wt%, a sufficient hardening effect cannot be obtained, and if the amount added exceeds 2.0 wt%, the formability thereof is markedly deteriorated.

When Nb is added, it is desirable that the addition amount be 0.05 to 2.0 wt% for the same reason as Zr. Furthermore M
Although o and V also have the same effect as each of the above elements, it is necessary to increase the addition amount thereof as compared with Ti, Al, Zr, and Nb.
If the addition amount is less than 0.05 wt%, sufficient strength cannot be obtained, and if it exceeds 2.5 wt%, the formability deteriorates.

Since W and Ta exhibit almost the same characteristics as Mo described above, if the addition amount is set to 0.05 to 2.5 wt%, it is possible to improve the strength.

Now, a pipe part made of such components is manufactured as follows.

This manufacturing method will be described by taking a shadow mask as an example. First, an alloy having the above-described composition is melted in a vacuum or an inert gas atmosphere to manufacture an ingot. Next, after repeatedly hot rolling the ingot, it is pickled and cold rolled. The rolling rate in the subsequent final rolling is
Although it can be changed depending on the liquid composition and the liquid temperature in the etching process which is the next step, it is usually desired to be 40% or more.

After that, the crystal grain size is controlled by adjusting the annealing temperature and the annealing time, and the shape of the in-pipe part is maintained by the final rolling. In this case, the crystal grain size of the material for the parts inside the pipe should be JIS-G0551.
It is preferable to set it to 8 to 12, which is defined by Further, it is desirable that the final adjustment rolling is performed at a rolling rate of 30% or less so as not to destroy the crystal texture. Further, since the crystal plane desirable for etching is usually (100), the crystal part may be used as the main surface to manufacture the in-tube component.

After that, a flat mask having a large number of holes formed through an etching process is prepared, and an annealing process that also serves as a solution treatment is performed in order to form a solid solution with the precipitation hardening component described above. This annealing is performed at a temperature of 700 to 1300 ° C. and in an inert gas. However, the amount of Cr or Mn added is 3 to 8 wt%
At this time, it is desirable to set the annealing temperature to 700 to 900 ° C. Further, when the addition amount is 3 wt% or less, or 8 to 10 wt%, it is desirable to set the temperature to 900 ° C. or higher.

What is important in this annealing treatment is to make the cooling rate as high as possible, which is inevitable for the solution treatment. By the way, if the cooling rate is slow, incipient precipitation of the precipitation hardening component starts, and the 0.2% proof stress of the flat mask increases. Therefore, the subsequent molding process becomes difficult. Further, this cooling is performed by filling the inside of the annealing furnace with an inert gas cooled to room temperature or lower.

After the annealing treatment as described above, the material (flat mask) is press-molded to obtain a shadow mask having a predetermined curved surface. Then, after the shadow mask is washed with, for example, trichloroethylene vapor, it is subjected to an aging treatment which also serves as a blackening treatment as described below.

Since this aging treatment also serves to blacken the shadow mask, air, water vapor, or carbon dioxide gas, for example, is used as the gas atmosphere. At this time, if the aging temperature is less than 500 ° C., the blackening process is delayed and the aging precipitation is also delayed, which is inappropriate. Further, if the aging treatment temperature is set to 800 ° C. or higher, the added precipitation hardening component is solid-solved in the matrix of the alloy structure and the pipe parts after forming do not become hard, which is not suitable. It is needless to say that the aging treatment temperature and the aging treatment time are appropriately determined according to the type of the precipitation hardening component elements added to the alloy.

In this case, as the blackening film, Cr _x Ni _y Fe _3-xy O ₄ (0 <x, y <3) or Mn _x Ni _y Fe is mainly used.
_3-xy O ₄ is generated and its adhesion is maintained. In addition, since the precipitation hardening component element is mainly concentrated at the interface between the blackening film and the metal, aging treatment of this shadow mask forms a surface with many crystal transitions on the shadow mask surface, which in turn forms on the shadow mask surface. The blackened film becomes a very rough surface, and the heat emissivity increases.

〔The invention's effect〕

Thus, according to the present invention, it is possible to add Cr to a predetermined Ni-Fe alloy to reduce its 0.2% proof stress and improve its formability. Moreover, unlike the conventional 32Ni-5Co-Fe alloy, there is no need to perform vacuum annealing at a high temperature, and the trouble of warm pressing is eliminated. Then, by annealing at 1200 ° C or less, the forming process can be sufficiently performed. Furthermore, the aging treatment that also serves as the blackening treatment after its formation can form a highly adherent blackened film for heat radiation on the surface and can sufficiently harden the formed parts, facilitating the handling. Can be planned. Further, since the strength can be sufficiently increased, the effect of preventing howling can be obtained.

Although the Ni-Fe alloy has been described as an example here, Fe-Ni-Co
It goes without saying that it is also applicable to the system alloys.

Example of Invention

Next, an embodiment of the present invention will be described by taking the production of a shadow mask as an example.

Example-1 First, an alloy ingot containing 36% Ni and Fe as main components, 2 wt% Cr, and other auxiliary components, and Ti added as an element of a precipitation hardening component was manufactured by vacuum melting. This ingot was prepared and hot-worked into a plate material having a thickness of 10 mm. This plate material was repeatedly annealed and cold worked to produce a coil with a thickness of 0.2 mm. Here, the final rolling rate is 80%, the adjusted rolling rate is 10%, and the grain size of the coil is JIS-
The particle size is 10 specified by G0551. A shadow mask was manufactured in the following manner using the material for the in-pipe parts thus manufactured. First, a photoresist was applied to both surfaces of the material, dried, and then a film having a reference pattern in the form of slots or dots was adhered to both surfaces thereof, and the photoresist was exposed and developed. By this development, the photoresist in the unexposed portion is dissolved and removed. Thereafter, the remaining photoresist was burned and hardened, and then an etching treatment with a ferric chloride solution was performed. Then, the remaining resist was removed by a hot alkali to prepare a flat mask as a master plate for the shadow mask.

Then, this flat mask was put in a box-shaped vacuum heating furnace and annealed in an atmosphere of 10 ⁻⁴ torr and 1000 ° C. to remove strain and improve its workability. The flat mask after the annealing was passed through a leveler to remove the plate strain, and at the same time, the stretcher strain in the forming process was reduced. The vacuum annealing was performed for the purpose of reducing the amount of dissolved C in the flat mask and reducing the crystal grain size. This facilitated the subsequent press molding.

Next, the flat mask was press-molded to obtain a shadow mask having a predetermined curved surface. At this time, it was confirmed that the 0.2% proof stress was small, its moldability was extremely good, and spring back did not occur. At the same time, it was confirmed that the characteristics of the shadow mask in the width direction and the length direction were uniform, and there was no occurrence of defective moldability due to so-called variations in the characteristics.

After that, the above shadow mask was washed with vapor of trichlorethylene and heated for 20 minutes in a continuous blackening furnace kept at 700 ° C. to grow a blackened film with good adhesion to a thickness of 1.5 μm to complete the shadow mask. . At this time, precipitation hardening occurred and the hardness was improved from Vickers hardness of 103 Hv to 150 Hv.

[Example-2 to Example-10] A shadow mask was formed in the same manner as in [Example-1] using alloys having the composition components shown in the following table together with the alloy components in [Example-1]. I made each.

In this table, the hardness of the material before and after the aging treatment that also serves as the blackening treatment and the degree of improvement in mechanical strength are also shown.

It was confirmed that the same effects as those of the previous examples were obtained in each of these examples.

Regarding the color picture tube incorporating the shadow mask of each example thus obtained, when the PD values at the four corners were examined, a shadow mask made of a conventional rimmed steel or Al-killed steel was incorporated. It was confirmed that the value was reduced to 1/2 compared to the PD value of the color picture tube. It was also confirmed that howling did not occur as in the case of using a shadow mask formed of an amber material.

By the way, in Comparative Examples 1 to 3 shown as a reference, when the hardness was 120 or more in Vickers hardness, the 0.2% proof stress was about 24 kg / mm ² , and press molding became difficult. In addition, the coefficient of thermal expansion also increased, causing a problem.

Although the formation of the shadow mask has been described as an example here,
A color picture tube can be obtained by similarly manufacturing an inner shield, a frame, a bimetal and the like. Other,
The present invention can be variously modified and implemented without departing from the scope of the invention.

[Brief description of drawings]

Fig. 1 shows the relationship between 0.2% proof stress and spring back, and Fig. 2 (a) shows M in 36Ni-Fe alloy containing Mn.
Fig. 2 is a diagram showing the relationship between 0.2% proof stress and the coefficient of thermal expansion with respect to the amount of n added.
It is a figure which shows the 0.2% yield strength with respect to the addition amount of r, and the relationship of a thermal expansion coefficient.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Shoji Kanto 50 Kamimabe, Yobu, Himeji City, Hyogo Prefecture Himeji Plant, Toshiba Corp. Stock company Toshiba Fukaya CRT factory (56) References JP 59-59861 (JP, A)

Claims (9)

[Claims] 1. Nitrogen of 25 to 45 wt% and Cr of 0.3 to 10 wt% in total.
2.5w in total consisting of at least one element selected from Ti, Nb, Al, Mo, V, W, Zr and Ta, and at least one of Mn.
After the alloy material consisting of a precipitation hardening component of t% or less, the balance Fe and unavoidable impurities is annealed at 700 to 1300 ° C. to reduce the yield strength of the alloy material, the alloy material is processed, and this is processed to 500 to 800. A method for manufacturing an in-pipe component, which is characterized by being blackened at ℃. 2. The precipitation hardening component Ti is 0.05 to 2.0 wt%.
The method for producing an in-pipe component according to claim 1, which is added. 3. Nb, which is a precipitation hardening component, is 0.05 to 2.0 wt%.
The method for producing an in-pipe component according to claim 1, which is added. 4. Al as a precipitation hardening component is 0.05 to 1.5 wt%.
The method for producing an in-pipe component according to claim 1, which is added. 5. Ta as a precipitation hardening component is 0.005 to 2.5 wt%
The method for producing an in-pipe component according to claim 1, which is added. 6. Mo as a precipitation hardening component is 0.005 to 2.5 wt%
The method for producing an in-pipe component according to claim 1, which is added. 7. V as a precipitation hardening component is 0.005 to 2.5 wt%
The method for producing an in-pipe component according to claim 1, which is added. 8. The precipitation hardening component W is 0.005 to 2.5 wt%.
The method for producing an in-pipe component according to claim 1, which is added. 9. The method for producing an in-pipe component according to claim 1, wherein 0.1 to 2.0 wt% of Zr which is a precipitation hardening component is added.