JPS59220291A - Production of titanium-clad steel plate - Google Patents

Abstract

PURPOSE:To produce a titanium-clad steel plate which has excelent adhesive performance and is free from camber by forming an oxide scale layer having a specific thickness on the surface to be intended to be separated of a plate assembled of a titanium clad steel material and subjecting the same to heating and finishing by rolling under specific conditions. CONSTITUTION:A titanium plate 2 having surfaces intended to be used as an adhesive surface 3 and a separating surface 7 is placed on a steel plate 1 which is a base material. An oxide scale layer is formed to >=40mu on the surface 7 and an excess metal 5 is placed on the surface 7. The plate assembled of such titanium-clad material is heated to a heating range of 400-750 deg.C prior to rolling and is subjected to rolling at least twice at 300-500 deg.C rolling finish temp. and >=25% draft. The draft is defined as {(the thickness of the plate prior to rolling-the thickness of the plate after rolling)/the thickness of the plate prior to rolling}X 100%.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a titanium clad steel plate by a rolling method.

When manufacturing titanium clad steel sheets by the pressing method, root bark p becomes a problem. In other words, when a titanium plate and a base steel plate are stacked one on top of the other and rolled, when the rolling temperature is about 600°C or higher, the titanium plate side of the assembled plate will elongate greatly and reverse to the steel plate side, and if the rolling temperature is below about 300°C, the opposite will occur. In some cases, it becomes difficult to continue rolling. For this reason, as shown in Fig. 3, a method can be considered in which the titanium plate 2 is sandwiched between carbon steel plates 1 of equal thickness with the titanium plate 2 in the center. A separating agent must be applied to prevent this. As this separating agent, it is possible to apply alumina powder or silicate powder with an organic binder, or by heating before rolling, a binder or carbon-containing gas is generated, and this is likely to cause contact. It adheres to the surface of the titanium plate and deteriorates the performance of the adhesive surface. At the same time, the separating agent enters the voids where bonding is to be made before rolling and during repeated rolling to prevent welding. Further, when rolling is completed, the edges are cut off at room temperature, and the drawing plates are separated at the separation plane, the hot-rolled clad steel plate warps toward the steel plate, and the cold-rolled clad steel plate warps toward the titanium plate by 9 degrees and this trench 1. It is difficult to turn it into a product.

An object of the present invention is to provide a method for manufacturing a titanium clad steel plate that has excellent adhesive performance and is free from cracks.

The gist of the present invention is as follows.

(1) One or both of the separation redundant surfaces of the titanium clad steel material assembly plate that is intended to have a suffix surface and a separation surface.

Form an oxide scale layer with a total thickness of 40μ or more,
The heating temperature of this titanium clad steel material assembled plate before rolling shall be 400°C or more and 750°C or less, the finishing temperature of rolling shall be 300°C or more and 600°C or less, and rolling at least twice at a rolling reduction of 25% or more. A manufacturing method for titanium clad steel sheets that is characterized by

(2) Form an oxide-scale layer of 40μ or more in total on one or both of the separation surfaces of the titanium clad steel material assembled plate, which are intended to be the adhesive surface and the separation surface, and before rolling this titanium clad steel material assembled plate. The heating temperature is 400°C or more and 750°C or less, the finishing temperature of rolling is 300°C or more and 600°C or less, and the rolled titanium cladding is rolled at least twice at a rolling reduction of 25 inches or more. After heat-treating the steel material assembly plate at a temperature of 550°C or more and 750°C or less, cutting off the end of the assembly plate,
A method for producing a titanium clad steel sheet, which is characterized by separating on a planned separation plane.

(3) Titanium cladding for contact and separation surfaces @
A total of 40 on one or both of the surfaces to be separated on the material assembly board.
An oxide scale layer of μ or more is formed, and the heating temperature of the titanium cracked steel plate is set to 400°C before rolling.
Above 750℃ or less, rolling finishing temperature 300℃
above and below 600°C, and rolling at least twice at a reduction rate of 25 inches or above, and the thus rolled titanium clad steel material assembled plate is heated at above 550°C and 750°C.
After heat treatment at the following temperature, the ends of the assembled plates are cut off and the titanium clad steel plates obtained by separating at the separation plane are rolled at a temperature of 400°C or less and a rolling reduction of 20% or less. Characteristic manufacturing method for titanium clad steel sheets.

The present invention will be described in detail.

Figures 1 to 3 show a working sheet of a titanium clad steel fabric assembly plate, which is the starting material of the present invention.
is the base steel plate, 2 is the titanium plate, 3 is the adhesive surface, 4 is the microhole,
5 is the waste material, 6il is the scrap material, and 7 is the separation surface. As shown in the figure, in a titanium clad steel material assembly plate having an adhesion surface 3 and a separation surface 7, an oxide scale layer with a total ratio of 40/1 or more is formed on one or both of the adjoining separation surfaces, Heating temperature before pressure IA: 400℃ or higher7
The temperature is 50°C or less, the starting and finishing temperature 'fc is 300°C or more and 600°C or less, and rolling is performed at least twice at a rolling reduction of 25% or more.

When one of the separation surfaces is a steel plate, this oxide scale is A
wiping with the scale generated by hot rolling in step ``f'';
One side of the separation surface: 750℃ or less if it is a titanium plate 5
A dense screen with good adhesiveness that can grow at temperatures above 00°C is preferred.

The total thickness of the oxide scale is 40 t to separate the drawing plates.
A thickness of t or more is good, but a school with a thickness of 200μ or more is undesirable because the scale tends to fall off. Iron or titanium oxide scale does not need to be coated with an ink coating like the alumina powder or silicate powder mentioned above, and since it is firmly attached to the surface to be separated, the problem does not occur.

In addition, if iron or titanium oxide scale enters the gap between the bonded limbs, it will be crushed by rolling and become harmless, and the uniform distribution will serve to prevent the diffusion of iron and carbon from the steel plate to the titanium plate. Become.

The upper limit heating temperature of 750°C is the limit at which diffusion of iron and carbon from the steel or bonded part to the titanium side is not observed.
The lower limit temperature of 400°C is the limit obtained by obtaining a finishing rolling temperature of 300°C. A finishing rolling temperature of 300° C. is not preferable because rolling with a general hot-rolling roll causes scratches on the roll. Titanium clad steel sheet, which is expected to have the highest demand (
Titanium plate strength JI8H4600, 1111+, Steel & Ka J
ISG 3103 2nd arm 6f! For titanium clad steel sheets (Ii), the rolling finishing temperature is 300°C or higher and 600°C.
Below, the deformation resistance is almost equal to 19, and rolling deformation (f) is less likely to occur, so this is the optimum rolling finishing temperature.

The purpose of rolling at least twice at a reduction rate of 25% or more is to ensure complete adhesion.Although the adhesion is insufficient in the first rolling, the unbonded surface is activated, and the next This is because the bonding is carried out under a large pressure of 25% or more.

Even if the rolled assembled plate does not have an apparent straight warp, when the ends are cut off and the plate is taken out as a titanium clad steel sheet, the residual stress is released and the warp usually occurs. In order to prevent this, it is desirable to perform stress relief annealing at a temperature of 550° C. or higher and 750° C. or lower, then cut off the ends of the assembled plates and separate them at the intended separation plane. However, in this case as well, due to the different negative thermal contraction υ of the steel plate (111+) and the titanium plate during the cooling process, a small warpage will occur again.The direction of warpage at this time is on the end side with a larger coefficient of thermal expansion. be.

To correct this, it is possible to roll the material at a temperature of 400° C. or lower, and within this temperature range, the edge side has a lower deformation resistance than titanium, and the warpage is eliminated and the thickness accuracy can be improved. At this time, a rolling reduction ratio of 20% or less is sufficient. After this, further cold rolling is carried out, or re-rolling is carried out at 550℃ or more.7
After annealing at 50° C. or lower, warm rolling or cold rolling can be continued.

The present invention will be described with reference to examples.

Table 1 shows the chemical composition of titanium plate, JIS) I460
This product is equivalent to type 01. Table 2Vi shows the chemical composition of base material steel plate and waste steel plate, and is equivalent to JIS G 31032 type.

Table 3 shows the experimental conditions and the contact evaluation results after rolling.

Adhesion criteria are JfS G 0601 and G 3
603, a shear strength of 14 kgi/rnm2 or more was considered good. The example of plate combination shown in Figure 2 is shown in Figure 1.
The test results were the same for the cases shown in Figures 3 and 3.

The dimensions of the assembled board during the test were thickness 28.51+Im, width 1
00 mm, length 200111111, after heating to specified temperature/rolling, first pass rolling reduction r+1J15
%, 25%, or 50%. After this, either air cool or immediately apply the second pass rolling reduction r2k15%.

After adding either 25% or 50 g, it was air cooled.

Table 3 shows the case where the downstream rate was 25% and the heating temperature was 750°C. After cooling to room temperature, the end portion was cut off and removed, and the amount of shear for the length of the clad plate, 100111 m, was expressed as a scale. The cracking becomes smaller when the finishing temperature of rolling is 600°C or lower. Also, the warpage was reduced by cold rolling, but this was because rolling was stopped when the warp became small. After two-pass rolling, Examples 19, 32, and 4 had good adhesion, and these had a decarburized layer depth of 20μ or more on the mating surface with the titanium surface of the steel plate and a thickness of oxide scale of 10μ or less, or This is the case when the thickness of the oxide scale on the mating surface with the steel plate is 10 /J or less, or the total thickness of the oxide scale on both mating surfaces is 10 μ or less.

Note that the oxide scale thickness of the titanium plate is the same on both sides, and the scale thickness of the waste steel plate in contact with the titanium plate is about 40 p, and the waste plate can be easily separated by cutting off the ends after rolling. ,Ta. The example in Table 3 is JIS G 3
This is the case when 1032a is used as the base material, but according to JIS
The tendency is the same for G 3 to 6 types.

The applicable material of the present invention is JIS G 3603 (198
This includes the laminated materials and base material equivalents shown as applicable materials in Table 2.

As described above, the present invention can provide an excellent titanium clad steel plate with excellent adhesion performance and no cracks, and therefore has great industrial benefits.

(JIS H46001 class equivalent product) (JIS G 31032 type equivalent product)

[Brief explanation of the drawing]

1 to 3 are longitudinal cross-sectional views of a titanium Clara P steel material assembled plate when carrying out the present invention. 1...Base material copper plate, 2...Titanium plate, 3...Tangulation 4
Surface, 4... Microhole, 5... Waste material, 6... Succession, 7
... Separation surface. Basis/Illustration 2 Criteria 3

Claims (3)

[Claims] (1) A total of 40μ on one or both of the surfaces to be separated of the titanium clad steel material assembly plate, which are intended to be the bonding surface and the separation surface.
The above oxide scale layer is completely formed, and the heating temperature before rolling of this titanium clad steel material assembled plate is set at 400°C or more and 750°C or less, and the rolling finishing temperature is set at 300°C or more and 600°C or less, and A method for producing a titanium clad steel sheet, comprising rolling at least twice at a rolling reduction of 25% or more. (2) Bonding thread...a total of 4 on one or both of the separation planned surfaces of the titanium clad steel material assembly plate that is planned to be the separation surface with i.
An oxidized school layer of 0μ or more is formed, and the heating temperature [-14
If the temperature is 00°C or more and 750°C or less, the finishing temperature of rolling is 3
00°C or more and 600°C or less, and rolling at least twice at a reduction rate of 25% or more, and the thus rolled titanium clad steel material assembled plate is heated to a temperature of 550°C or more and 75%.
A method for producing a titanium clad steel plate, which comprises heat treating at a temperature of 0° C. or lower, cutting off the ends of the assembled plate, and separating the plate at the intended separation plane. (3) Oxidation scale rt with a total of 40 μ or more on one or both of the surfaces to be separated of the titanium clad steel material assembly plate that are intended to be the bonding surface and the separation surface! The heating temperature of this titanium clad steel material assembled plate before rolling is 400℃.
℃ or more and 750℃ or less, and the rolling finishing temperature is 300℃.
℃ or more and 600℃ or less, and rolling at least twice at a rolling reduction of 2596 or more, and the thus rolled titanium clad steel material assembled plate is heated to a temperature of 550℃ or more and 750℃ or more.
After heat treatment at a temperature of 1°C or lower, the ends of the assembled plates are cut off, and the titanium clad steel plates obtained by separating on the separation plane are fully rolled at a temperature of 400°C or lower with a reduction rate of 20% or less. A method for manufacturing titanium clad steel sheets characterized by: