JPS6243794B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for manufacturing titanium clad steel sheets by explosive crimping. The increasing sophistication of technology in the chemical industry has placed stricter demands on corrosion-resistant materials, and titanium is a material that is in increasing demand due to its excellent corrosion resistance. However, titanium is still produced in small quantities on an industrial scale, and clad steel plates are easier to obtain when using thick plates, and clad steel plates are also used for bending, welding, and other assembly work into equipment. It's advantageous. It is impossible to directly join titanium and steel to create this titanium-clad steel plate using any method other than explosive crimping, and methods have been proposed that use silver solder or other third metals as a bonding material. Its bonding performance is not sufficient and it has not yet been put into practical use. Explosive crimping is the only method that directly joins titanium and steel, and while soft titanium materials with high malleability exhibit good bonding properties, hard materials with poor malleability either do not bond at all or do not bond at all. It peels off easily even when
The reality is that it cannot be put to practical use, and this tendency is also related to the physical properties of steel; the higher the tensile strength of steel, the more difficult it becomes to join titanium and steel. On the other hand, from the perspective of those who use titanium clad steel sheets, there is an increasing demand for titanium clad steel sheets that are not only resistant to corrosion, but also use hard titanium in consideration of fluid erosion. In order to meet this demand, for example, the "multilayer metal clad steel" shown in Japanese Patent Publication No. 44-6468, the "titanium clad steel" shown in Japanese Patent Publication No. 43-432, and the
Although we researched and considered various documents related to conventional technologies such as "Titanium/Titanium/Stainless Clad Steel" shown in Publication No. 29192, we found that there were no reports on the difficulty of explosive crimping of hard titanium plates and on how to improve this. In the prior art, soft titanium and hard titanium are uniformly listed and are not helpful. Therefore, various studies were conducted on the so-called explosive crimping conditions, such as the type, amount, arrangement of explosives, detonation method, distortion of the mixture or base material, and polishing roughness, and experiments were repeated. It was not possible to obtain a good bond by crimping to stainless steel. The present invention improves these drawbacks,
The purpose is to provide a method for manufacturing titanium clad steel sheets using hard titanium. That is, the present invention has a tensile strength of 40 Kg/1 when manufacturing a hard titanium clad steel plate by explosive crimping.
This is a method for producing the desired hard titanium clad steel plate using a carefully selected titanium plate with a diameter of 28 kg/mm ^{2 or less, a yield strength of 28 kg/mm 2} or less ^, and an elongation rate of 40% or more as an intermediate welding material. The titanium plate used as the intermediate welding material used in the present invention has a tensile strength of 40 kg/mm ² or less and a yield strength of 28
It is important that the titanium plate has the properties of Kg/ ^mm2 or less and elongation rate of 40% or more.If the titanium plate does not have the above properties, the reliability of bonding with steel will be poor, and in addition, it will have hardness. When explosive crimping is applied to titanium plates, peeling or cracking may occur. When producing hard titanium clad steel sheets in this way, if the bonding properties between the intermediate welding material and the steel are excellent, the titanium intermediate welding material and hard titanium must have different properties other than tensile strength, yield strength, and elongation. Since they are almost the same metallurgically with only slight differences in chemical components such as impurities or trace components, hard titanium can be arbitrarily selected from industrially produced materials with malleability. It is. The titanium plate used as the intermediate welding material can be selected in the range of 1 mm or more and 12 mm or less, but we take into account that it is easy to obtain, has excellent bonding properties, and that the thinner the welding material, the less waste. If so, 2 mm or more and 4 mm or less is appropriate. As described above, the present invention makes it possible to obtain a hard titanium clad steel sheet with good crimp properties by interposing soft titanium as an intermediate bonding material between hard titanium and steel. It is now possible to arbitrarily select hard titanium clad steel sheets that are difficult to obtain, and it is now possible to use titanium clad steel sheets with excellent corrosion resistance, making it possible to cope with increasingly severe operating conditions in chemical plants. . The method for producing the hard titanium clad steel sheet of the present invention is to use a conventional method, that is, to explosively bond an intermediate welding material onto a base steel plate to produce a clad plate made of the intermediate welding material and the base steel plate. , a method in which a hard titanium plate is explosively crimped onto the intermediate welding material of this clad plate, or an intermediate welding material is placed on the base steel plate, a hard titanium plate is further placed on this intermediate welding material, and this It can be manufactured by any method that produces a three-layer assembly using a single explosive crimping process. The present invention will be explained below using examples. Example 1 A hard titanium plate was placed concentrically on the upper surface of the base steel plate shown in Table 1 with an appropriate gap, and an explosive placed on the entire upper surface of the soft titanium plate was detonated from one corner. A soft titanium clad steel plate with a large base material area was obtained by explosive crimping using a conventional method. Next, after cleaning and flattening the upper surface of the soft titanium clad steel plate, a hard titanium plate is placed with an appropriate gap, and explosive crimping is carried out in the same manner as above using a conventional method to form a large area of the base material. A clad steel plate consisting of hard titanium/soft titanium/mild steel was obtained.

[Table] When this clad steel plate was subjected to ultrasonic flaw detection, it was found that the outer periphery was approximately 10 to 15 mm wide and had a sagging part on the end face, making it difficult to detect flaws, but the other areas were completely crimped over the entire area, indicating a good bond. It has been made. Example 2 The materials shown in Table 2 were explosively crimped in the same manner as in Example 1 to obtain hard titanium/soft titanium/mild steel clad steel plates.

[Table] When this clad steel plate was subjected to ultrasonic flaw detection in the same manner as in Example 1, the crimped state was good and no unbonded areas were observed. Examples 3 to 5 The materials shown in Table 3 were subjected to explosive crimping in the same manner as in Example 1, and the obtained clad steel plates were subjected to ultrasonic flaw detection, and the crimping was good in all cases, with no unbonded areas observed.

[Table] Comparative Example A composite material (hard titanium plate) shown in Table 4 was placed on the top surface of the base steel plate shown in Table 4 with an appropriate gap, and an explosive placed on the entire top surface of the hard titanium plate was placed. An explosion was caused from one corner and explosive crimping was carried out in the same manner as in Example 1 to obtain a hard titanium/SF50 clad steel plate with a large base material area. When this clad steel plate was subjected to ultrasonic flaw detection, there was no pressure bonding near the detonation part, and the area was about about the entire area.
It was 20%.

【table】

Claims (1)

[Claims] 1 When manufacturing hard titanium clad steel plates by explosive crimping, the tensile strength is 40 kg/mm ² or less and the yield strength is 28.
A method for producing a hard titanium clad steel plate, characterized in that a titanium plate having a kg/mm ² or less and an elongation rate of 40% or more is used as an intermediate welding material.