JPH06234084A - Titanium clad stainless steel composite material - Google Patents

Abstract

PURPOSE:To produce the titanium clad stainless steel composite material having high joint strength of a cladding metal and a base metal and excellent hot rollability by joining titanium which is the cladding metal and a stainless steel which is a base metal by an explosive welding method and joining an excess metal to the titanium layer side. CONSTITUTION:The titanium (pure titanium, corrosion resistant alloy titanium, etc., having a thickness of about 1/5 to 1/20 the thickness of the base metal) which is the clean cladding metal having smooth surfaces and the stainless steel (austenitic steel of about <=0.08wt.% carbon content) which is the base metal are joined by the explosive welding method. The excess metal (ordinary steel, etc., having about 10mu remaining thickness at the end of the rolling) is joined to the titanium layer side of the stainless steel slab. The titanium clad stainless steel composite material having the excellent hot rollability is thus obtd. and the production of a steel plate having excellent corrosion resistance and heat resistance is produced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a titanium clad stainless composite material having excellent hot rolling property.

[0002]

2. Description of the Related Art Titanium is a metal having excellent weather resistance and corrosion resistance. Japan is surrounded by the sea, so the humidity is high, and the corrosion of metals associated with environmental changes reduces resource consumption.
It also leads to a great loss of social resources such as unsightly appearance due to corrosion.

Therefore, titanium, which is a so-called maintenance-free metal material having good corrosion resistance, light weight and excellent strength and requiring no surface treatment such as painting, is used as a roof material,
Although it is being used as various exterior materials including outer wall materials, it is currently not used as a general-purpose material because of its high price. On the other hand, although stainless steel is advantageous in terms of cost, it has insufficient corrosion resistance and durability compared to titanium,
In particular, it is not suitable as an exterior material that requires a long life.

In order to solve such a problem, a composite steel sheet has been proposed in which titanium is used as a joining material and joined to stainless steel as a base material. For example, there is provided a composite steel sheet in which titanium, which is a laminated material, is joined to stainless steel, which is a base material, by a polyester adhesive. However, in this composite steel sheet, the coefficient of thermal expansion of the base material and the base material are different from each other, which causes a shift due to aging, or deterioration of the adhesive force due to aging. Due to the different bending stress of the material, there is a problem that bending is difficult and welding is impossible.

Therefore, a method of producing a titanium clad steel material by the explosive deposition method is conceivable. According to this method, the joint interface between the laminated material and the base material is instantly formed in a cold state.
It is possible to provide a composite material in which a carbide, a nitride, or a layered Ti—Fe-based metal compound is not formed, has clean boundaries, and has a high bonding strength. Since this explosive slab has a gentle hardness distribution in the vicinity of the interface, the subsequent hot rolling and cold rolling working conditions can be set broadly and the range of manufacturing conditions is widened. The degree of freedom in setting the spreading conditions is great, and excellent quality characteristics can be secured.

Further, as a method of avoiding a decrease in bonding strength due to an intermetallic compound or an embrittlement layer formed at the interface between the base material and the base material, a brittle layer is formed by sandwiching the base material, the metal intermediate layer and the base material. Of forming a joint by interposing a joining intermediate material between titanium and a base material and defining a gap between the joining intermediate material and titanium. A method of rolling by avoiding the formation of an intermetallic compound of titanium and a base metal by an intermediate material (Japanese Patent Laid-Open No. 63-56370), or an explosive Fe-based thin metal deposited on titanium, and this material and the base material. A method of assembling a composite slab and hot rolling (Japanese Patent Laid-Open No. 2-295682) has been proposed.

[0007]

However, with the conventional sandwich construction, not only the material cost is high, but the productivity is low, and moreover, the rolling is carried out in a vacuum or under reduced pressure, which is economical and economical. It was a heavy burden. Further, among the stainless steels, the temperature during hot rolling of austenitic stainless steel sheets having good corrosion resistance is not higher than the solution temperature, the deformation resistance is too high, and hot rolling becomes very difficult. It is preferably carried out. Even with titanium, the hot rolling temperature is
80 ° C.) or higher is preferable, but a thick and hard oxide film is formed in an oxidizing atmosphere. When this oxide film is included in the lower oxygen-containing hardened layer, the thickness reaches several hundreds of μm, resulting in loss of expensive titanium, and this oxide film is crushed during the next cold rolling, resulting in a fine powder. Therefore, this powder has a problem that countless fine flaws are formed on the surface of titanium.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a titanium-clad stainless steel composite having a large joining strength between a laminated material and a base material and excellent hot rolling property. Is to provide wood.

[0009]

In the composite material of the present invention, a discarded material is joined to the titanium layer side of a titanium clad stainless slab obtained by joining titanium as a joining material and stainless steel as a base material by an explosive deposition method. It is characterized by consisting of.

[0010]

[Operation] Since the slab is manufactured by the explosive deposition method, the joint interface is instantly formed in the cold state, and the carbide, nitride or Ti
-Fe-based intermetallic compounds are not formed, have clean boundaries, and have high bonding strength. Further, since the explosive-bonded slab has a gentle hardness distribution in the vicinity of the interface, there is no concern about interfacial peeling or defective shape during rolling, and excellent quality characteristics can be secured. Furthermore, since there is no intermetallic compound at the interface of the explosive slab and the structure is metallurgically intimately adhered, and the waste material is bonded to the titanium layer side of the slab, titanium is protected by the waste material during hot rolling. Since it does not need to be rolled in vacuum or under reduced pressure, it can be hot-rolled in the atmosphere, and it not only requires a small load economically and economically, but also the temperature condition of hot-rolling is high at low deformation resistance. Can be set to, and high pressure rate can be adopted,
There is no loss of power cost, roll life and energy, and there is no loss of titanium due to oxidation or curing by oxygen, which is extremely advantageous in terms of cost.

The present invention will be described in detail below. In the present invention, the base material is stainless steel, and any of austenitic steel and ferritic steel can be applied, but austenitic steel having excellent corrosion resistance is preferable. The carbon content of the stainless steel is preferably 0.08% by weight or less. . If it exceeds 0.08% by weight, a carbide that becomes an embrittlement layer tends to be formed at the joint interface with titanium.

Further, the titanium used as the laminating material has a smooth surface and is clean, and it is preferable that the longitudinal width and the lateral width of the base material are larger than those of the base material by, for example, about 50 mm. The thickness of titanium is preferably 1/5 to 1/20 of the base material. 1 /
If it is larger than 5, the ratio of expensive titanium occupies too large, and there is no economic effect to make a clad steel plate.
Further, the difference in material characteristics between titanium and stainless steel is not alleviated, which makes it difficult to form products of various shapes. On the other hand, if it is less than 1/20, titanium may be locally broken during hot rolling or forming, and the base material, stainless steel, may be exposed, and the desired corrosion resistance and durability can be secured. It tends to be difficult. Incidentally, in the present invention, the titanium of the joining material is not limited to pure titanium, and titanium alloys such as corrosion resistant alloy titanium, α alloy titanium, near α alloy titanium, α-β alloy titanium, and β alloy titanium can be adopted. is there.

Next, in the present invention, the base material stainless steel and the joining material titanium are joined by the explosive welding method. First, the stainless steel slab is finished smooth by scarfing and the scale is obtained. Is removed and used as the base material. In order to obtain a strong interfacial bond strength, the stainless steel slab and the titanium of the laminated material are arranged so as to have a constant gap. For example, it is 1 mm. This is detonated by an explosive having an appropriate detonation speed, for example, 2000 m / sec or less. Next, depending on the location of the explosive, the peripheral edge of titanium, which is the composite material, has a shape protruding from the end of the stainless steel slab, so it is mechanically cut and removed to produce a titanium clad stainless slab with excellent end face shape. To do. In this case, pure iron (carbon content 0.003% or less) or Ni is inserted as an intermediate material between the stainless steel and the titanium layer of the slab to suppress the formation of titanium carbide during slab heating and hot rolling. You may do it. The thickness of this intermediate material is preferably 1 mm or less. For example, when manufacturing a slab, it may be sandwiched between stainless steel as a base material and titanium as a combined material and simultaneously subjected to explosive pressure bonding. With this intermediate material, no carbide is generated, and the intermetallic compound is only Ti-Fe system, and the joint strength and the deformation resistance are remarkably improved.

A discarded material is joined to the titanium layer side of this titanium clad stainless slab to form the titanium clad stainless composite material of the present invention. The composite material of the present invention is rolled to produce a titanium clad stainless steel sheet.However, the waste material causes the formation of an oxide film and a hardened layer due to oxygen invasion into titanium before and during hot rolling. Not only can it be reliably prevented and hot rolling can be performed in the atmosphere, but the loss of titanium will be eliminated. Therefore, both stainless steel and titanium have low deformation resistance during hot rolling and can be easily rolled, for example, a rolling temperature of 1100 ° C. or higher, which is the solution temperature of austenitic stainless steel sheets. As discard material, ordinary steel or 5%
Cr steel, Si-containing low alloy steel, Mn-containing low alloy steel, etc., or oxides such as alumina-based oxides and silica-based oxides such as water glass can be adopted, but in terms of cost, removability and workability. Plain steel is preferred. For example, in the case of ordinary steel, this discarded material may be provided by joining ordinary steel and titanium by the explosive deposition method and then joining the composite material and stainless steel by the explosive deposition method. ,Titanium,
Ordinary steel may be provided by explosion-depositing at the same time. Further, ordinary steel is joined to one side of titanium by seam welding or the like, and the composite material and stainless steel are joined by an explosion-deposition method. It may be provided. In the case of an alumina-based oxide, the titanium clad stainless slab may be applied on the titanium layer side with a roll or the like and dried. Further, the thickness of the discarded material is preferably such that several tens of μm remains at the end of rolling in consideration of removal after hot rolling. If it is too thin, the titanium in the lower layer may be exposed and oxidized during hot rolling. In addition, in order to further improve the hot rolling property, not only the titanium layer side of the slab but also the stainless steel side of the slab may be joined with a discard material to ensure a well-balanced rolling property.

The composite material of the present invention is preferably 1100 ° C.
It is heated at ˜1300 ° C. for 1 to 5 hours and hot-rolled in a reverse or tandem type with several stages, for example, a pass schedule using 5 stands. In this case, when the product sheet thickness is set to 1/20 or less of the composite material of the present invention (total rolling rate 95% or more), it is difficult to obtain a desired sheet thickness only by hot rolling, and therefore it is continued. Cold rolling is required.

When the product sheet thickness is 1/20 or more of the composite material of the present invention and the rolling ratio is 90 to 95%, cold rolling is not always necessary, and the ability of the hot rolling mill and the surface of the steel sheet as a product are required. It depends on the smoothness and the shape of the steel plate itself.
These properties are better when finished by cold rolling,
Since the manufacturing cost increases, it may be selected appropriately. In any case, after hot rolling, the waste material containing the oxide film and the oxide film on the stainless steel are removed. For this removal, chemical means such as pickling method or mechanical means such as grinding method can be adopted. For example, when ordinary steel is used as the discard material, it is removed together with the scale by immersing it in a nitric acid-hydrofluoric acid-based pickling solution.

After removing the discarded material together with the scale, cold rolling is performed. The cold rolling rate naturally varies depending on the plate thickness of the product to be manufactured, and the number of passes also varies, but if it is necessary to take a large cold rolling rate such that the deformation resistance difference causes product warpage, different peripheral speeds are used. It is necessary to change the frictional resistance between the roll and the material between rolling and other upper and lower surfaces.

In this case, it is advantageous that the work roll itself has a diameter as small as possible in terms of securing the rolling ratio, improving the shape and reducing energy. Although the smoothness of the surface of the steel sheet is obtained by cold rolling, the steel sheet after cold rolling may be annealed and temper-rolled depending on the application. Thus, the titanium clad stainless steel sheet produced from the composite material of the present invention can be suitably adopted in various fields as an industrial material having excellent corrosion resistance and heat resistance such as acid resistance, seawater resistance, and corrosion resistant gas. .

Next, the present invention will be specifically described based on examples. In the following,% indicating the ratio of components is% by weight. (Example 1) C: 0.06%, Si: 0.80
%, Mn: 1.50%, P: 0.03%, S: 0.02
%, Ni: 8.50%, Cr: 18.80%, Fe: B
al. And, thickness 30mm, length 2000mm, width 900m
The austenitic stainless steel slab of m was finished by smoothing with scarfing, and the scale was removed to obtain a base material.

Next, a plain steel plate having the same size and a thickness of 0.5 mm is seam welded to one surface of a JIS type 1 industrial pure titanium plate having a thickness of 3.0 mm, a length of 2100 mm, and a width of 1000 mm, which is a laminated material. These were joined together on a stainless steel slab with the ordinary steel plate as the upper surface so that the interval was 1 mm, and the materials were blasted with an explosive having an explosive velocity of 1500 m / sec or less.

Then, the titanium clad stainless composite material was manufactured by mechanically cutting and removing the peripheral edge portion of the titanium plate, which was a laminated material, protruding from the end portion of the stainless steel slab. (Example 2) Component C: 0.06%, Si: 0.62
%, Mn: 0.63%, P: 0.03%, S: 0.02
%, Cr: 17.20%, Fe: Bal. And the thickness is 30
A titanium clad stainless composite material was produced in the same manner as in Example 1 except that a ferritic stainless steel slab having a size of 2,000 mm, a length of 2000 mm, and a width of 900 mm was used. (Example 3) A titanium clad stainless slab was used as an intermediate material between a stainless steel slab and a titanium plate in an amount of 0.1 m.
Except that it was manufactured by placing a pure iron plate of m thickness and bombarding it.
A titanium clad stainless composite material was manufactured in the same manner as in Example 1. (Example 4) A titanium clad stainless slab is used as an intermediate material between a stainless steel slab and a titanium plate in an amount of 0.1 m.
A titanium clad stainless composite material was produced in the same manner as in Example 2 except that a Ni plate having a thickness of 99.9% and a purity of 99.9% was placed and bombarded. (Example 5) An ordinary steel plate having the same size and a thickness of 0.5 mm was previously joined to the lower surface of the stainless steel slab by seam welding,
A titanium clad stainless composite material was produced in the same manner as in Example 2 except that the ordinary steel plate was welded to the upper surface of the titanium plate and the lower surface of the stainless steel slab. Example 6 Instead of plain steel, 100 parts by weight of flake-shaped atomized powder of 200 mesh or less and xylene 60
%, 80 parts by weight of bronze powder suspended in 40% of alkyd phthalate resin and 100 parts by weight of toluene are mixed to prepare a slurry-like alumina-based oxide, which is applied to one side of a titanium plate. A titanium-clad stainless composite material was produced in the same manner as in Example 1 except that a waste material having a weight of 20 g / m ² was provided by drying. (Comparative Example 1) A titanium clad stainless composite material was produced in the same manner as in Example 1 except that the ordinary steel plate was not joined to one surface of the titanium plate. (Comparative Example 2) A titanium clad stainless composite material was produced in the same manner as in Example 2 except that the ordinary steel plate was not joined to one surface of the titanium plate. Next, in order to evaluate the hot rolling property of the titanium-clad stainless steel composite material produced in this way, a titanium-clad stainless steel sheet was produced under the following conditions. (Manufacturing Example 1) The titanium-clad stainless steel composite material of Example 1 was heated at 1200 ° C for 5 hours and hot-rolled by a reverse type using one stand to obtain a titanium-clad stainless steel hot-rolled steel sheet. The rolling rate was 80%. in this case,
The formation of scale was observed on the ordinary steel plate and the stainless steel plate.

After that, it is dipped in a mixed acid of nitric acid and hydrofluoric acid at 40 ° C. to completely remove the scale produced during hot rolling and the remaining ordinary steel layer to form a titanium clad having a thickness of 6.6 mm. A stainless steel plate was manufactured. (Production Example 2) Titanium-clad stainless steel having a thickness of 2.5 mm was produced in the same manner as in Production Example 1 except that the titanium-clad stainless steel composite material of Example 1 was heated at 1250 ° C. for 5 hours to change the hot rolling rate to 92%. A steel plate was manufactured. (Production Example 3) The titanium-clad stainless steel composite material of Example 1 was heated at 1250 ° C. for 5 hours and hot-rolled in a reverse type using one stand to obtain a titanium-clad stainless steel hot-rolled steel sheet. The rolling rate was 80%. in this case,
The formation of scale was observed on the ordinary steel plate and the stainless steel plate.

After that, it was immersed in a mixed acid of nitric acid and hydrofluoric acid at 40 ° C. to completely remove the scale produced during hot rolling and the remaining ordinary steel layer. Thereafter, cold rolling was performed using a 6-high cold rolling mill (work roll diameter 200 mm) 2 stands. Mineral oil was used as the rolling oil. The rolling rate was 80%. In this way, the total rolling rate is 96%
A titanium clad stainless steel plate having a product thickness of 1.3 mm was manufactured. (Production Example 4) The hot rolling rate was 60% and the cold rolling rate was 8%.
The total rolling rate was 92 in the same manner as in Production Example 3 except that the content was 0%.
%, A titanium clad stainless steel plate having a product thickness of 2.5 mm was manufactured. (Production Example 5) A titanium-clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.5 mm was prepared in the same manner as in Production Example 4 except that the titanium-clad stainless steel composite material of Example 2 was heated at 850 ° C for 3 hours. Manufactured. (Production Example 6) From the titanium-clad composite material of Example 3, as in Production Example 4, the total rolling rate was 92% and the product thickness was 2.6.
mm titanium clad stainless steel plate was produced. (Production Example 7) From the titanium-clad stainless steel composite material of Example 4, a titanium-clad stainless steel sheet having a total rolling ratio of 92% and a product thickness of 2.6 mm was produced in the same manner as in Production Example 5. (Production Example 8) A titanium-clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.5 mm was prepared in the same manner as in Production Example 4 except that the titanium-clad stainless steel composite material of Example 1 was heated at 1120 ° C for 5 hours. Manufactured. (Production Example 9) The same procedure as in Production Example 3 was repeated except that the titanium-clad stainless steel composite material of Example 1 was heated at 980 ° C for 5 hours so that the hot rolling rate was 60% and the cold rolling rate was 80%. A titanium clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.5 mm was manufactured. (Production Example 10) A titanium-clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.5 mm was produced from the titanium-clad stainless steel composite material of Example 5 in the same manner as in Production Example 4. (Production Example 11) A titanium clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.5 mm was produced from the titanium clad stainless steel sheet of Example 6 in the same manner as in Production Example 4. (Manufacturing Example 12) Manufacturing Example 1 except that the titanium clad stainless steel composite material of Comparative Example 1 was subjected to pickling time of the hot rolled titanium clad stainless steel 4 times to completely remove the scales on both sides. Similarly, a titanium clad stainless steel sheet having a total rolling rate of 80% and a product thickness of 6.6 mm was manufactured. (Production Example 13) Similar to Production Example 2 except that the pickling time of the hot rolled titanium-clad stainless steel sheet after hot rolling was set to 4 times and the scales on both sides were completely removed from the titanium-clad stainless steel composite material of Comparative Example 2. Then, a titanium clad stainless steel plate having a total rolling rate of 92% and a product thickness of 2.5 mm was manufactured. (Production Example 14) From the titanium-clad stainless composite material of Comparative Example 1, except that the pickling time of the hot-rolled titanium-clad stainless steel sheet after hot rolling was set to 4 times to completely remove the scales on both sides and then cold rolling was performed. In the same manner as in Production Example 4, a titanium clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.3 mm was produced. (Production Example 15) From the titanium-clad stainless composite material of Comparative Example 2, except that the pickling time of the hot-rolled titanium-clad stainless steel hot rolled steel sheet was set to 4 times to completely remove the scales on both sides and then cold rolling was performed. In the same manner as in Production Example 4, a titanium clad stainless steel sheet having a total rolling rate of 92% and a product thickness of 2.3 mm was produced. The following qualities were evaluated for the titanium clad stainless steel sheet produced in this manner. The results are shown in Table 2. A. Appearance The appearance was visually observed to see if there were any abnormalities.

⊚: Uniform appearance ○: Substantially uniform appearance x: When there are surface defects (roughness, turning of titanium layer, exposure of stainless steel layer, etc.) B. Presence / absence of non-bonded portion The presence / absence of a non-bonded portion was examined by ultrasonic flaw detection according to JIS G3603.

◯: No non-bonded part was observed Δ: A slight non-bonded part was recognized ×: Significant non-bonded part was recognized C. Existence of Carbide in Joined Part A cross section of the joined part was observed with a microscope in accordance with JIS G3603 to examine the state of precipitation of carbide.

⊚: No precipitation of carbides was observed ◯: Very slight precipitation of carbides was observed ×: Significant precipitation of carbides was observed D. Shear strength (kgf / mm ² ) E. Bending and bending back test Punch (thickness 10 x width 30 mm) with the laminated material on top
The sample is bent by 90 ° to bend it, and then the base material is placed on the upper surface, and the sample is pushed back with a punch to return the sample straight. In this process, a large shearing force acts on the joint surface between the base material and the laminated material. The peeling condition was visually observed.

◯: No peeling ×: Peeling occurred F. Corrosion resistance and durability test The sample after the bending test carried out in Evaluation E was used for 7 days for 7 days.
It was immersed in 5% salt water at 0 ° C., and the presence or absence of permeation of the salt water into the interface and the accompanying peeling was observed.

◯: No peeling was observed ×: Peeling was observed Also, in this case, the occurrence of rust on the base material on the cut end face was observed.
I guessed. ◯: No rust was found ×: Rust was found Table 1 Manufacturing conditions  Base material Laminated material Intermediate material Discarded material Product Rolling rate (%) Seed Thickness (mm) Thickness (mm) Seed Thickness (mm) Thickness (mm) HR CR TR Production Example 1 O 30 3 None Fe 0.5 6.6 80-80 2 O 30 3 None Fe 0.5 2.5 92-92 3 O 30 3 None Fe 0.5 1.3 80 80 96 4 O 30 3 None Fe 0.5 2.5 60 80 92 5 F 30 3 No Fe 0.5 2.5 60 80 92 6 O 30 3 Yes (Fe) Fe 0.5 2.6 60 80 92 7 F 30 3 Yes (Ni) Fe 0.5 2.6 60 80 92 8 O 30 3 No Fe 0.5 2.5 60 80 92 9 O 30 3 No Fe 0.5 2.5 60 80 92 10 O 30 3 No Fe 0.5 2.5 60 80 92 11 O 30 3 None Al ₂ o ₃ 0.5 2.5 60 80 92 12 O 30 3 No No 6.4 80-80 13 O 30 3 No No 2.3 92-92 14 O 30 3 No No 1.1 80 80 96 15 F 30 3 None None 2.3 60 80 92 Table 2 Quality evaluation test  Appearance Non-bonded part Carbide Shear strength Bending test Immersion testPeeling rust Production example 1 ○ ○ ○ 30 ○ ○ ○ 2 ○ ○ ○ 33 ○ ○ ○ 3 ◎ ○ ○ 42 ○ ○ ○ 4 ◎ ○ ○ 39 ○ ○ ○ 5 5 ◎ ○ ○ 37 ○ ○ × 6 ◎ ○ ○ 48 ○ ○ ○ 7 ◎ ○ ○ 43 ○ ○ × 8 ◎ ○ ○ 43 ○ ○ ○ 9 ◎ ○ ○ 36 ○ ○ ○ 10 ◎ ○ ○ 43 ○ ○ ○11 ○ ○ ○ 43 ○ ○ ○ 12 × × ○ 20 × × ○ 13 × × ○ 22 × × ○ 14 × △ ○ 25 × × ○15 × △ ○ 25 × × × From the results of Table 2, titanium produced from the composite material of the example
Clad stainless steel sheet is also concerned with hot rolling at high temperature.
Instead, the discarded material prevents the titanium from oxidizing and is uniform and beautiful.
It had a beautiful appearance. Especially in Production Example 10,
Put a scrap material on the bottom of the composite stainless steel slab
Therefore, not only the titanium surface but also the stainless steel surface
The appearance was also very beautiful. Also, there is no formation of carbides,
The bonding strength is large, and particularly in Production Examples 6 and 7,
Non-bonded part is not formed at all, and the bonding strength is very high.
It has become a thing. In addition, Production Examples 4 and 5 and Production Example 6,
As is clear from Fig. 7, the higher the hot rolling temperature, the stronger the bonding strength.
Tends to grow. As described above, according to the embodiment of the present invention,
There is a titanium clad stainless steel plate manufactured from
Is excellent in all qualities and can be used as exterior materials such as roofing materials and wall materials.
It can be seen that it can be suitably adopted.

On the other hand, in the titanium clad stainless steel sheet manufactured from the composite material of the comparative example, the titanium surface was found to be rough. This is due to the oxide film formed by hot rolling at a high temperature, and particularly in Production Examples 14 and 15, the oxide film was crushed by cold rolling to form innumerable flaws on the titanium surface. Was there. Further, in these production examples, there is a non-bonded portion, and therefore, the shear strength is low, and peeling was observed in the bending test and the dipping test, because the oxide film formed during hot rolling is hard. It is considered that this is because the rolling load is less likely to be transmitted to the bonding interface due to the non-uniformity. Further, it is found that due to the formation of this oxide film, the product thickness becomes smaller than that manufactured from the composite material of the example as shown in Table 1, and titanium is lost.

[0030]

According to the present invention, since the joining interface between the laminated material and the base material is instantly formed in a cold state by the explosive deposition method, a carbide or a nitride or a layered Ti-Fe based metal compound is formed. However, it has a clean boundary and the bonding strength is increased. Further, since the explosive-bonded slab has a gentle hardness distribution in the vicinity of the interface, there is no concern about interfacial peeling or defective shape during rolling, and excellent quality characteristics can be secured. In addition, there is no intermetallic compound at the interface of the blast slab, and the structure is metallurgically adhered.
Moreover, since the discarded material is joined to the titanium layer side of the slab, titanium is protected by the discarded material during hot rolling, and there is no need to roll in vacuum or under reduced pressure, and hot rolling can be performed in the atmosphere. In addition to being economically and economically burdensome, the hot rolling temperature condition can be set to a high temperature with low deformation resistance, a high pressure reduction ratio can be adopted, and there is no loss of power cost, roll life or energy. Moreover, there is no loss of titanium due to oxidation or curing by oxygen, which is extremely advantageous in terms of cost.

Claims (4)

[Claims] 1. A titanium-clad stainless steel composite comprising a titanium-clad stainless slab, which is formed by joining explosive-bonding titanium as a joining material and stainless steel as a base material, and a waste material is joined to the titanium layer side. Material. 2. The titanium clad stainless composite material according to claim 1, wherein an intermediate material layer is interposed between the stainless steel and the titanium layer. 3. The titanium-clad stainless composite material according to claim 1, wherein the discarded material is also joined to the stainless steel side of the titanium-clad stainless slab. 4. The titanium-clad stainless composite material according to claim 1, 2 or 3, wherein the discarded material is ordinary steel.