JPS60118396A - Production of thin clad sheet material consisting of au or au alloy and stainless steel having high work hardenability - Google Patents

Abstract

PURPOSE:To produce a thin clad sheet material consisting of Au or Au alloy and stainless steel by superposing an annealed stainless steel sheet material and an Au or Au alloy sheet material via Ni and subjecting the materials to rolling and soft annealing under adequate conditions. CONSTITUTION:A stainless steel sheet material which is annealed to <=180 hardness Hv and has 1.0-3.0mm. thickness and an Au or Au alloy sheet material clad with an Ni or Ni alloy sheet material are superposed with said Ni or Ni alloy layer in-between and the sheet materials are subjected to hot rolling at 30-70% draft at 600-800 deg.C in a gaseous H2 or inert gaseous atmosphere contg. H2, by which the sheet materials are clad. The hot rolled clad material obtd. in the above-mentioned way is subjected to >=1 pass of cold rolling at <=75% cumulative draft including intermediate annealing in a vacuum or non-oxidizing atmosphere to a final sheet thickness. The thin clad sheet thus obtd. is held for 1- 12hr at 700-850 deg.C, by which the sheet is soft-annealed. The thin clad sheet material consisting of the Au or Au alloy and the stainless steel having high work hardenability and high difficultly workability is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for producing a clad thin plate material made of Au or an Au alloy and a difficult-to-work stainless steel that has desired properties such as high corrosion resistance but also has remarkable work hardening properties. It is related to.

In recent years, A has been used as connectors for watch bands and electronic components, etc.
Demand for clad thin plate materials of u or Au alloy and stainless steel is increasing.

By the way, conventionally, a thin plate material of Au or Au alloy and stainless steel is produced by cladding the Au or Au alloy plate material with Ni or Ni alloy plate material for the purpose of improving the bondability with the stainless steel. After combining Ni or Ni and cladding by cold rolling, it is heated to a temperature of 600 to 650°C for 1
It was common to fabricate the Au or Au alloy with a focused softening anneal held for ~12 hours.

Therefore, under these rad thin plate manufacturing conditions, the processing strain in the stainless steel layer of the resulting clad plate cannot be removed.
Since the hardness was not sufficiently reduced, the punching and bending properties of the thin clad plate itself tended to be poor.

For this reason, the stainless steels applicable to the manufacture of Au or Au alloy clad stainless steel sheet materials have been limited to relatively soft stainless steels such as SUS 385.

However, soft stainless steels such as SUS 385 steel generally have poor corrosion resistance, and Au or Au alloy clad products using them have the problem of being susceptible to discolored rust during use. It had

Therefore, 5Us316, 5US317, which has good corrosion resistance,
Alternatively, attempts have been made to clad stainless steel such as 5US317L, but since these stainless steels have extremely high work hardening properties, the conventional cladding thin plate manufacturing techniques described above cannot be used with high-quality Au or Au alloys. It was only confirmed that it was impossible to use a thin cladding plate.

From the above-mentioned viewpoint, the present inventors have discovered that it is possible to manufacture a clad thin plate material of Au or Au alloy and stainless steel with high work hardening properties, which also has good punchability and bending workability. As a result of thorough research, we found that: ■ We annealed the stainless steel sheet that will serve as the alloy for the cladding material to sufficiently reduce its hardness, and also determined the cladding conditions by hot rolling, the subsequent cold rolling conditions, and the final annealing. If the conditions are selected appropriately, the hardness of the stainless steel layer after finishing will be Hv220 or less, which provides good punching and bending workability, and even if stainless steel with high work hardening properties is used as an alloy, it will have good workability. It is possible to realize rad thin plate material.
6- ■ Furthermore, in cladding processing, if the Au or Au alloy composite material is clad in advance with Ni or Ni alloy material and then overlapped with the stainless steel plate material with the Ni or Ni alloy layer in between, the Ni In addition, new knowledge was obtained that the Ni alloy layer acts as a bonding intermediate material, improving the cladding properties between the Au or Au alloy material and the stainless steel material, and suppressing the occurrence of peeling and blistering in the cladding part. .

The present invention has been made based on the above findings, and includes: (a) a stainless steel plate material having a thickness of 1.0 to 3.0 wn, which has been annealed to have a hardness of 180 or less; N1 alloy plate material and clad Au or Au aggregation plate material are stacked with the Ni or Ni alloy layer in between, (b) this stacked body is heated with an inert gas containing N2 (including only Hz gas). Heating temperature in atmosphere:
600-800℃.

The material is clad by hot rolling at a reduction rate of 30 to 70%, and (C) the resulting hot rolled clad material is then coated with 4
- after having undergone one or more cold rollings with a cumulative reduction of 5% or less with intermediate annealing in a vacuum or non-oxidizing atmosphere to reach the final thickness; (d) the cladding sheet is heated to a temperature Near 00-850℃.

Holding time: 1 to 12 hours of softening annealing is performed in steps (a) to (d) to produce Au or Au alloys with good punchability and bending workability, and stainless steel with high work hardenability. It has a K% characteristic in that it manufactures clad thin plates with steel.

The stainless steel with high work hardening properties used in the method of the present invention is, for example, 5US316.5US.
Examples include Fe-Cr-Ni-Mo stainless steels represented by 316L, 5US317, and 5US317L, but are not limited thereto. However, the Fe-Cr-Ni-M.

Stainless steel has excellent corrosion resistance, so products made of this as an alloy and clad with Au or Au alloys are comparable to products made of SUS 385 stainless steel and copper alloys, which have traditionally been used for this type of purpose. As a result, there are almost no problems such as discoloration or rust formation. Also,
If a stainless steel containing even less Ci is used, the corrosion resistance of the resulting product will be further improved.

If the hardness of the stainless steel plate material used as the alloy is 180 or less in Vickers hardness (Hv),
Hv with good cladding properties during cladding processing and satisfactory punching and bending properties after final softening annealing
: Finished with a hardness of 220 or less, Hv: 180
If stainless steel with a hardness exceeding lv: 220 is used, not only will the cladding properties be poor and peeling will occur easily, but even after final annealing, only a product with a hardness exceeding lv: 220 can be obtained.
This will cause problems in subsequent punching and bending workability.

Also, the thickness of the stainless steel plate material used as the alloy is 1.
If it is less than 0 m, the temperature will drop significantly during rolling, defects will occur on the cladding surface, and the hardness will become too high.
If the plate thickness exceeds 3.0 m, it is necessary to increase the reduction amount to ensure the rolling rate during cladding, which is a disadvantage in that the product is likely to bend or warp, making it difficult to perform stable cladding. will occur. For these reasons, the hardness of the stainless steel plate used should be Hv: 180 or less, and the plate thickness should be 1.0 to 3. OIIrn, respectively.

The cladding process is carried out by heating the material to 600 to 800°C and hot rolling at a rolling reduction of 30 to 70% while completely preventing oxidation of the material in an H2-containing inert gas atmosphere. If the heating temperature is less than 600°C, complete rudding will not be achieved and blistering or peeling will occur, while if heated to a temperature exceeding 800°C, Au or Au alloy may melt or break during rolling. Even if the rolling reduction ratio at the time of cladding is less than 30 inches, complete rudding will not be achieved;
If the processing rate exceeds %, cracks may occur in the stainless steel, misalignment may occur between the stainless steel layer and the Au or Au alloy steel layer during cladding, or the hardness after final annealing may become Hv.
: Heating temperature: 600 because it does not go below 220
-800°C9 Rolling ratio: 30 to 70% 7- It was determined that hot rolling and cladding were to be performed.

In order to finish the obtained clad material to the desired thickness, it is necessary to perform intermediate annealing and cold rolling at least once, but if the cumulative reduction rate during each intermediate annealing exceeds 75%'t- , even after the final softening annealing, the hardness of the stainless steel layer remains lv
:220 or less, the cumulative reduction rate of cold rolling performed during intermediate annealing was set to be 75 inches or less.

The final softening annealing is performed at a temperature of 700 to 850°C for 1 to 30 minutes.
This is done by heating and holding for 12 hours.
Stainless steel does not soften sufficiently at temperatures below 00°C,
On the other hand, this is because heating at a temperature of 850° C. or higher causes the surface of Au or Au alloy to become rough. If the heating time is less than 1 hour, the stainless steel will not be sufficiently softened, while if it is heated for more than 12 hours, the surface will become rough.

This final softening annealing is preferably carried out in vacuum to prevent surface discoloration and oxidation. This is because, at a heating temperature of 700 to 850°C, the stainless steel and Au alloy surfaces are very likely to discolor when heated in an inert gas atmosphere or a phosphorus-containing inert gas atmosphere, and in order to prevent this, This is because it is necessary to lower the dew point of the atmospheric gas in the trench to an extent that is practically impossible, and even if it were possible to do so, the cost would be extremely high.

In this way, since it is practical to perform the final softening annealing in a vacuum, the composition of the Au alloy to be used should include components having a saturated vapor pressure of 1 x 10-5 Hg or more at 700°C. It is wise to choose one that does not contain it. If it contains components with high vapor pressure, the final softening annealing will cause Au
The surface of the alloy may become rough and discolored.

Next, the present invention will be explained using examples and comparing with comparative examples.

Example First, a Ni-clad Au or Au alloy plate material shown in Table 1 was coated with Fe-Cr of each stacking thickness also shown in Table 1.
-Ni-Mo stainless steel (C: 0.03% by weight
.

St: 0.11% by weight, Mn: 0.15% by weight
, P: 0.001% by weight, S: 0.001
Weight%, Ni: 12.5% by weight.

Cr: 17.8% by weight, MO: 2.1% by weight, the rest being Fe and other impurities) The plate material was stacked with a Ni layer in between, and this was similarly cladded under the conditions shown in Table 1. Cold rolling with intermediate annealing and final annealing were performed to obtain a 0.5-strip clad thin plate material.

The width of the material is 25 m, the length is 1000 m, and the degree of vacuum during final vacuum annealing is 5 x 10 Torr.
It was below.

For the cladding material of Au or Au alloy and Ni, prepare an Au or Au alloy plate and a Ni plate with dimensions: 30 wn x 100 m, and prepare the cladding material with the thickness ratio according to the cladding ratio shown in Table 1. Then, they were stacked so that the total thickness was 8 m, and then placed in a mild steel package. After degassing the inside of the package, the package was heated to 700°C and then hot-reduced by 30% once. In addition, it was manufactured by rolling and cladding. Of course, after cladding, the plate is cold rolled to the finished plate thickness and cut to a predetermined length and width.

In addition, as shown in FIG.
After stacking the Ni-clad Au or Au alloy plate material 1 on the stainless steel plate material 2 so that the Ni layer forms an intermediate layer, it is charged into the furnace core tube 4 of the heating furnace 3, and the atmosphere gas inlet 5)
A method was adopted in which the material was heated to a predetermined temperature while supplying atmospheric gas, and then rolled. Note that in FIG. 1, reference numerals 6 and 6 indicate rolling rolls.

The thus obtained Au or Au alloy clad stainless steel sheet annealed material was measured for the hardness of its stainless steel layer, subjected to repeated close bending tests, and immersed in artificial sweat at 40°C for 48 hours. A corrosion test was conducted and the results are shown in Table 2.

The results shown in Table 2 show that even if Au or Au alloy clad steel sheet material is manufactured using highly work-hardened and highly corrosion-resistant stainless steel as an alloy, the stainless steel layer can be formed by the method of the present invention. It can be seen that a product with good punchability and bending workability with a hardness of Hv220 or less can be obtained.

As described above, according to the present invention, Au or an Au alloy made of stainless steel, which has excellent properties such as corrosion resistance but has not been used conventionally because of its high work hardenability, can be used. It is a clad thin plate material of steel and stainless steel, and it can be manufactured relatively easily with good punching and bending properties, and it can be used as a material for decorative items such as watch bands and as wood for electronic parts. This brings about industrially useful effects such as the ability to further improve its performance.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an example of a method of cladding N1 clad Au or Au alloy material and stainless steel material. In the drawings, 1...Ni clad Au or Au alloy plate material, 2...
Stainless steel plate material, 3... Heating furnace, 4... Furnace core tube, 5... Atmosphere gas inlet, 6... Rolling roll. Applicant Mitsubishi Metals Co., Ltd. Agent Tomi 1) Kazuo and 1 other person 16-

Claims (1)

[Scope of Claims] (a) A stainless steel plate material with a thickness of 1.0 to 3.0 m whose hardness is Hv: 180 or less by annealing, and Ni
Or, stacking a Ni alloy plate material and a cladding Au or Au alloy plate material with the Ni or Ni alloy layer in between,
can) This stacked body was heated with an inert gas containing H2 (Hz
In an atmosphere (including only gas), heating temperature: 600~
800℃. (c) The obtained hot-rolled cladding material is subjected to cumulative reduction with intermediate annealing in a vacuum or a non-oxidizing atmosphere. (d) The clad thin plate is subjected to cold rolling at a rate of 5% or less 11 times or more to reach the final thickness, and then: (d) the clad thin plate is heated at a temperature of 700 to 850°C. A method for producing a clad thin plate material of Au or an Au alloy and highly work hardenable stainless steel, characterized by subjecting the material to softening annealing for a holding time of 1 to 12 hours.