JPH0661631B2 - Method for producing titanium clad steel plate without roughening titanium surface and separating agent for clad - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a titanium clad steel sheet.

Steel is cheap but susceptible to corrosion, while titanium has good corrosion resistance but is expensive. Therefore, in order to make the best use of the characteristics of the both, clad steel having titanium on the surface and steel as the central portion is widely used in chemical devices and the like.

The present invention provides a method for producing such a titanium clad steel sheet with a high yield by eliminating rough skin in the production stage.

[Prior Art] Conventionally, when a titanium clad steel plate is manufactured by hot rolling,
For example, as shown in JP-A-60-18205 and JP-A-60-170586, carbon steel or stainless steel, which is a base material, may be used with Cr, Ni, Cu, and Insert a thin plate or foil such as Mo, put titanium or titanium alloy as a bonding material, fix it with welding, heat it and heat it, but Ti and Fe are very brittle intermetallic compounds at high temperature. Since it is generated, it cannot be welded directly. Zirconium oxide, etc. is used as a separating agent on the surface where the titanium or titanium alloy, which is the composite material, faces each other with the titanium or titanium alloy, which is the composite material, facing inward. The paste consisting of is applied and assembled in a sandwich form to fix the steel base materials together by welding, or one set is used to stack the titanium or titanium alloy as the inner material and stack the steel as the discarded material. Apply a paste made of zirconium oxide, etc. as a separating agent to the surface where the titanium or titanium alloy, which is the base material, and the steel, which is the discard material, come into contact, and assemble it in a semi-sandwich shape. It has been fixed and heated to 600 ℃ to 1000 ℃ and then hot rolled to produce titanium clad steel sheets.

[Problems to be Solved by the Invention] According to the above-described manufacturing method, the titanium or titanium alloy surface which is the laminated material is inside the assembly slab and does not contact the rolling roll, causing rough skin. The rolling compression bonding method is a highly productive manufacturing method, but this rough skin requires maintenance of the surface after manufacturing, which lowers the yield of expensive titanium and titanium or titanium alloy is thin in the case of thin plate manufacturing. Since it cannot be maintained, it has been an obstacle such as not becoming a product or causing a surface breakage during cold rolling.

[Means for Solving the Problem] The present inventors considered that the roughening of the titanium surface was due to the lack of lubricity of the conventional separating agent.

As a result of various studies based on this idea, stable oxides such as aluminum oxide and zirconium oxide are the most effective for separation after sandwich type or semi-sandwich type production. It has been found that the titanium surface will be roughened as it is because it has no lubricity. Therefore, it is necessary to provide lubricity to this, but it is necessary to have lubricity at the titanium clad manufacturing temperature as high as 600 ° C or higher. It was It was also found that the inclusion of mica, potassium phosphate salt, and potassium titanate salt is effective for imparting lubricity at a high titanium clad production temperature of 600 ° C. or higher.

The present invention will be described in detail with reference to FIGS. 1 and 2. First
FIG. 2 is a conceptual diagram of a sandwich-type assembly cross section of a titanium clad steel plate, and FIG. 2 is a conceptual diagram of a semi-sandwich type assembly cross-section of a titanium clad steel plate. 1
Is a base metal such as carbon steel or stainless steel, 2 is a titanium or titanium alloy as a composite material, and 3 is C as an intermediate material
It is a thin plate or foil of r, Ni, Cu, Mo, etc., but may not have an intermediate material. 4 is an auxiliary frame material and 5 is a separating agent. At this time, in the method according to the present invention, mica or potassium phosphate salt or potassium titanate salt is contained alone or in combination as a separating agent in a total weight ratio of 30% or more and 80% or less,
The balance is coated with a separating agent composed of zirconium oxide and aluminum oxide.

Next, the limiting conditions of the present invention will be described. The present invention is a sandwich type in which titanium or titanium alloy surface does not become rolling skin because titanium or titanium alloy surface does not become surface rolling roughness when titanium or titanium alloy surface does not become rolling skin when manufacturing titanium clad steel sheet.
It was time for the semi-sandwich type manufacturing method. Manufacturing temperature of hot rolled titanium clad steel plate is generally 600 ℃
Since it is ~ 1000 ° C, it was set to this range. Since titanium is a very active metal, it is easy for them to adhere to each other, and especially when rolling a thin plate with a high reduction ratio, it cannot be separated with an antioxidant such as water glass, so the base of the separating agent is a stable oxide of aluminum oxide. , Zirconium oxide. This ratio is not particularly limited because there is no difference between aluminum oxide and zirconium oxide. As a result of actually hot-rolling and manufacturing titanium clad steel sheets for various substances having a lubricating action, it was found that mica, potassium phosphate, and titanic acid are substances that maintain a lubricating action at the titanium clad steel production temperature and achieve a good titanium surface. Since it was a potassium salt, it was decided to include these alone or in combination. If the content ratio is small, the lubricating effect is exhibited, but if the weight ratio is less than 30%, it is not sufficient. Therefore, the content is determined to be 30% or more. If the weight ratio exceeds 80%, the separability will deteriorate, so 8
It was set to 0% or less. Since there is no difference between mica, potassium phosphate salt and potassium titanate salt, they may be used alone or may be combined in any ratio without any particular limitation.

It should be noted that the present invention also includes modifications within a range that does not change the gist of the present invention, for example, manufacturing with a structure of three or more layers in which a sandwich type structure or a semi-sandwich type structure is combined.

[Working] Mica, potassium phosphate, potassium titanate 600 ° C
It has a lubricating effect at the above-mentioned high temperature production temperature of titanium clad, and ensures a good surface texture of the titanium surface. Mica, potassium phosphate salt, and potassium titanate salt, alone or in combination, have a total weight ratio of 30% or more 8
The content is 0% or less, and the balance is stable oxides such as aluminum oxide and zirconium oxide, so that separability can be ensured, and titanium or titanium alloy is inside the assembly so that the titanium surface is not a rolling surface. Even in such a case, it is possible to manufacture a titanium clad steel plate without roughening of the titanium surface.

[Examples] Example-1 Carbon steel sheet of SS41 having a thickness of 16 mm x width of 100 mm x length of 150 mm, an intermediate material of 0.6 mm thickness x width of 90 mm x 140 mm length of commercial copper, and a laminating material of 3 mm thickness × 90 mm wide × 140 mm long JI
A sandwich type slab as shown in Fig. 1 was made using titanium of S II type, and at the level shown in Table 1. 4.
After manufacturing a 0 mm thin plate by hot rolling, the welded part was removed and the titanium surface was observed. Measure the surface roughness and 100μ at Hmax.
The following were judged to be good. The joint surface between the carbon steel as the base material and the titanium as the composite material was maintained with a hand glider. The surface roughness of this care surface was 30 μ in Hmax. Also, commercially available natural mica was used as K ₄ P ₂ O ₇ as potassium phosphate salt and K ₂ Ti ₆ O ₁₃ as potassium titanate salt as mica. The total amount of the separating agent applied was 50 g. The results are also shown in Table 1.

From the levels No1 to No8 and No12, the effectiveness of separating aluminum oxide and zirconium oxide can be seen. Level No1
It is understood from No. 10 that the content of mica, potassium phosphate and potassium titanate is 30% to 80%.
In level No. 11, molybdenum disulfide usually has a large lubricating action, but it is considered that the lubricating action disappeared due to the change to molybdenum oxide at a high temperature of 890 ° C, and it is understood that the lubricity at the titanium clad steel plate manufacturing temperature is important.

Example-2 Carbon steel plate of SS41 having a thickness of 16 mm × width of 100 mm × length of 150 mm as a base material, a commercially available oxygen-free copper having a thickness of 0.6 mm × width of 90 mm × a length of 140 mm as an intermediate material, and a thickness of 3 mm × width of a laminated material. 90mm x length 140m
JIS II type titanium of m, thickness 10mm × width 100mm × for discarded materials
A carbon steel sheet of SS41 with a length of 150 mm was used to create a sandwich type slab as shown in Fig. 2. After heating to 890 ° C, a 4.0 mm thin plate was manufactured by hot rolling, and then the welded portion was removed to remove titanium. The surface was observed. The joint surface between the carbon steel as the base material and the titanium as the composite material was maintained with a hand glider. The surface roughness of this care surface is 30μ at Hmax.
Met. At this time, K ₄ P ₂ O ₇ was used as potassium phosphate and the weight ratio was 35% aluminum oxide and 3% zirconium oxide.
A separating agent of 5% and potassium phosphate 30% was used. The total amount of the separating agent applied was 50 g. As a result, the separability was not problematic, the titanium surface was good, and the roughness was about 90 μm.

Example-3 A base material of 57 mm thick x 600 mm wide x 5000 mm long SS41 carbon steel sheet, an intermediate material of 1.0 mm thick x 590 mm wide x 4900 mm commercially available oxygen-free copper, and a laminated material of 3 mm thick x Width 590 mm x length
Two sandwich type slabs as shown in Fig. 1 were prepared using 4900 mm JIS II type titanium. At this time 1
As a comparative example, the separating agent is aluminum oxide 5 by weight.
0% and 50% zirconium oxide are used, and the other one is an example of the present invention, in which the separating agent is aluminum oxide in a weight ratio.
5%, zirconium oxide 35%, potassium phosphate salt 30
% Was used. The total amount of the separating agent applied was 8 kg. After heating these to 890 ° C, hot strip mills were used to prepare 4.0 mm hot rolled sheets. Both could be manufactured into a coil of about 1.8 tons. The welded portions on both sides in the width direction were trimmed and removed, and each was separated into two pieces. Comparing the titanium surfaces after separation, the former had a rough surface (the surface roughness was 50 μm or more in Hmax.), But the latter was a good titanium surface and the roughness was 100 μm or less in Hmax. These were pickled with sulfuric acid and hydrofluoric nitric acid, and then cold rolled to 1.0 mm. As a result, in the former case, the titanium surface broke when cold rolled to 1.5 mm and the cold rolling was discontinued, whereas in the latter case, the titanium surface could be cold rolled to 1.0 mm without tearing.

[Advantages of the Invention] According to the present invention, it becomes possible to manufacture a titanium clad steel plate with a high yield by a roll-bonding method with high productivity, and it is possible to make a cold-rolled thin plate of the manufactured hot-rolled steel plate. The resource and industrial benefits that can be obtained are large, such as the expansion of the manufacturable range.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a sandwich-type assembly of titanium clad steel plates, and FIG. 2 is a conceptual diagram of a semi-sandwich type of titanium clad steel plates. 1 ... Base steel such as carbon steel or stainless steel 2 ... Composite material titanium or titanium alloy 3 ... Intermediate material copper or copper alloy 4 ... Auxiliary frame material 5 ... Separation agent 6 …… Abandoned material, 7 …… Welding area

Claims (2)

[Claims] 1. A base material is steel, and a laminated material is titanium or a titanium alloy, and the laminated material is titanium or a titanium alloy. In the method of manufacturing a titanium clad steel plate by stacking steel as a waste material inside and assembling it in a semi-sandwich shape, heating it to 600 ℃ ~ 1000 ℃ and hot rolling it, titanium or titanium alloy comrades or titanium Alternatively, one or more kinds of mica, potassium phosphate salt, and potassium titanate salt may be present on the surface where the titanium alloy and the steel, which is a discarded material, come into contact with each other, and the total content thereof is 30% to 80% by weight. And the balance is a titanium surface characterized by applying a separating agent consisting of one or two of zirconium oxide and aluminum oxide. Method for producing a no-les titanium clad steel plate. 2. One or more of mica, potassium phosphate and potassium titanate, the total content of which is 30% to 80% by weight, the balance being zirconium oxide and aluminum oxide. A clad separating agent used in the production of a titanium clad steel sheet consisting of one or two of the above.