JPH04182080A - Manufacturing method of nickel-based alloy rolled clad steel plate with excellent base material toughness - Google Patents

Abstract

PURPOSE:To manufacture optimum rolled clad steel plate of nickel base alloy by limiting component series of a base metal, rolling conditions before solution treatment, acceleration cooling conditions, further, solution treatment temperature and cooling speed. CONSTITUTION:A laminated plate of clad steel plate is made of nickel base alloy containing Cr: 0.5-25%, Mo: 0.5-30%, Mo+Cr>=25%. The base metal of the clad steel plate is composed of C: 0.020-0.050%, Si: 0.02-1.0%, Mn: 0.50-1.50%, P<=0.02%, S<=0.01%, Nb: 0.02-0.05%, Ti: 0.005-0.03%, Al: 0.001-0.06%, N<=0.007% and the balance Fe. After the clad steel plate is heated at 1100-1250 deg.C, it is hot-rolled and finished at >=700 deg.C and after rolling is over, it is put in acceleration cooling to a temperature above the room temperature and below the transformation point Ar3 of the base metal at a speed >=5 deg.C/sec. Further, solution treatment is performed at 1100-1200 deg.C, then, the clad meal is cooled at a speed >=1 deg.C/sec. In this way, it is possible to manufacture optimum nickel base alloy rolled clad steel meal excellent in the toughness of the base metal.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a nickel-based alloy rolled clad steel sheet that has both high corrosion resistance of the laminated material and high strength and toughness of the base material.

[Prior art]

Reaction tanks, pressure vessels, and their peripheral equipment in chemical plants such as oil and gas production and refining plants and desulfurization equipment are exposed to high temperatures and
They are used under high pressure conditions and are often exposed to gases containing corrosive gases such as H, S, Co, etc., as well as atmospheres containing oxidizing agents and reducing agents.

In environments such as those used in very severe corrosive environments, it is necessary to use highly rust-resistant alloys, such as nickel-based alloys, which have high corrosion resistance. However, these materials generally have low yield strength, so if they were made of solid material, they would have thick walls and would be very expensive, so it is said that the use of clad steel plates is suitable from an economical point of view. As an example, ``Method for manufacturing clad molded body'' is proposed in Japanese Patent Application Laid-Open No. 199719/1983. Here, in weight%,
C: 0.02% or less, (Nb+Ti+V) 50.02
%, and (A12 +Ti+Zr)XN≧0.005%
The base material is steel with Cr: 20.0 as a component.
~30.0%, Ni: 4.0-35.0%, Ao:
After cladding the laminate with 3.0-4.0% and the main balance being Fe, it was transferred to a temperature range of 1000-1100°C, then quenched at a cooling rate of 1-b to 620°C, and then cooled. This is a method of cooling in still air at a rate of 5 to b/min. As another example, as in the "Method for Manufacturing Nickel-Based Alloy Rolled Clad Steel Sheet" proposed by the present applicant, the rolling reduction is 50% or more at 900°C or lower in the base material composition and controlled rolling before heat treatment. A method has been developed to produce a base material with excellent toughness after high-temperature solution heat treatment under a combination of rolling conditions in which rolling is completed at a temperature of 700° C. or higher and 850° C. or lower.

[Problem that the invention seeks to solve]

In the method for manufacturing a rolled clad steel sheet described above, it is necessary to avoid impairing the corrosion resistance of the laminate and the strength and toughness of the base material.

Recently, with the expansion of the uses of clad steel plates, higher corrosion resistance of the laminated material is also required. One of the products that satisfies this requirement is Cr: 0.5% by weight.
% or more and 25% or less, Mo: 5% or more and 30% or less, and M
Examples include nickel-based alloys containing 225% o + Cr. However, this alloy has poor hot workability;
Another problem is that intermetallic compounds that cause deterioration of corrosion resistance are generated during rolling, and rolled clad steel sheets with excellent corrosion resistance cannot be produced by heat processing that combines rolling and cooling.

Therefore, in order to ensure the corrosion resistance of this type of laminated material, C
r, 1 to eliminate the intermetallic compound consisting of Mo.
It is necessary to maintain the temperature at a high temperature of 100° C. or higher and then cool it at a rate that prevents the formation of intermetallic compounds.

However, when solution heat treatment is performed at high temperature after rolling,
Conversely, a new problem arises in that the toughness of the base material decreases.

In order to solve this problem, for example, in the above-mentioned "method for manufacturing nickel-based alloy rolled clad steel sheet" proposed by the present applicant, in order to improve the toughness of the base material, the composition system and the rolling This method provides a method that can improve the strength and toughness of the base material after solution heat treatment by controlling the finishing temperature, but if the hot workability of the laminate is poor, such rolling is If this is done, another problem arises: the laminate material will crack during rolling, making it impossible to manufacture a crad steel plate.

The present invention aims to solve the above problems.

The purpose of the present invention is to provide a method for manufacturing an excellent nickel-based alloy rolled clad steel plate that satisfies the corrosion resistance of the laminated material and the strength and toughness of the base material.

[Means and effects for solving the problems] In order to achieve the above object, the present invention provides a method of reducing Cr: 0.5 by weight%.
% or more and 25% or less, Mo: 5% or more and 30% or less, and M
o + Nickel-based alloy containing 225% Cr is laminated on at least one side of the steel plate as a laminating material for clad steel plates, and in weight%, C: 0.020% or more 0.050%
Below, Si: 0.02% or more and 1.0% or less, Mn:
0.50% or more and 1.50% or less, P: 0.02% or less, S: 0.01% or less, Nb: 0.02%
Ti: 0.005% or more and 0.05% or more, Ti: 0.005% or more and 0.05% or more.
03% or less, Al: 0.001% or more and 0.06% or less, N: 0.007% or less, and the balance is Fe and unavoidable impurities. After heating to 1100°C or higher and 1250°C or lower, hot rolling is carried out to a finishing temperature of 700°C.
After completing the rolling, accelerated cooling is performed at a cooling rate of 5° C./second or higher to a temperature of room temperature or higher and lower than the Ar3 transformation point of the base material, and further, solution heat treatment is performed at a temperature of 1100° C. or higher and 1200° C. or lower, The basic feature is that it is then cooled at a rate of 1° C./second or more. The above laminate material is weight%: Cr: 0.5% or more and 25% or less, Mo: 5%
In addition to containing 30% or more and Mo+Cr≧25%, it further contains one or more of the following: W: 3% to 10%, CO: 0.5% to 10%, Fe: 20% or less However, a nickel-based alloy can be used in which the remainder consists of Ni and unavoidable impurities. - On the other hand, as the above-mentioned base material, in weight%, C: 0.020% or more o, oso%
Below, Si: 0.02% or more and 1.0% or less, Mn:
0.50% or more and 1.50% or less, P: 0.02% or less, S: 0.01% or less, Nb: 0.02%
Ti: 0.005% or more and 0.05% or more, Ti: 0.005% or more and 0.05% or more.
03% or less, Al: 0.001% or more and 0.06% or less, N: 0.007% or less, and furthermore, C
u: 0.1% or more and 1.0% or less, Ni: 0.1% or more and 1.0% or less, MO=0.01% or more and 0.10% or less, V: 0.01% or more and 0.10% A steel containing one or more of the following, with the balance consisting of Fe and unavoidable impurities, can be used.

In the present invention, from the viewpoint of ensuring the corrosion resistance of the laminated material, the heating temperature was set at 1100°C or higher for the purpose of eliminating intermetallic compounds consisting of Cr and Mo. However, from the viewpoint of ensuring the toughness of the base material, The heating temperature is 125
It is necessary to keep the temperature below 0℃. In addition, when hot rolling is performed by heating within that temperature range, it is better to keep the finishing temperature as low as possible from the perspective of improving base material toughness, but 7
If the temperature was lower than 00°C, the laminate would crack during rolling, so the finishing temperature was set to 700°C or higher.

Furthermore, the most distinctive feature of the present invention is a configuration in which accelerated cooling is performed after rolling.
The reason why the cooling rate from room temperature to a temperature below the Ar3 transformation point of the base material after rolling was limited to 5° C./sec or more is necessary for improving the base material toughness, as will be described later.

On the other hand, in the present invention, in the solution heat treatment after rolling and accelerated cooling, the solution heat treatment temperature is set in the range of 1100° C. or more and 1200° C. or less for the same reason as in the heat treatment before rolling described above. Furthermore, the reason why the cooling rate in the cooling treatment after the solution heat treatment is set to 1° C./second or more is to avoid impairing the corrosion resistance of the laminated material.

In the process of obtaining the above manufacturing conditions, the present inventors conducted various tests, the details of which will be explained below.

Figure 1 shows 5ONi-1, a typical nickel-based alloy.
6Cr-21Mo-4Fe-lCo-51 to 1150
After heating to ~1250℃ and rolling under various rolling conditions, 20℃
3 seconds at 1120°C and after rolling.
Hold for 0 minutes, then 0.5°C/sec, l'c/sec, 15°C
Corrosion resistance when subjected to solution heat treatment at a cooling rate of 23% H2So, -1.2%
The results evaluated by the HCQ test are shown. The corrosion resistance of the laminated material is inferior to that obtained by solution heat treatment even when it is heated at 1250°C, finished at 1075°C, and then acceleratedly cooled at a rate of 20°C/sec. In addition, heating was performed at 1150°C, and 900°C
If accelerated cooling is performed after finishing rolling at 680℃ with a rolling reduction of 80% below ℃, the corrosion resistance will not only be inferior to that subjected to solution heat treatment, but also when rolling is completed. Occasionally, cracks occurred in the nickel-based alloy.

Furthermore, even among those subjected to solution heat treatment, when cooled at a rate of 0.5°C/sec, the corrosion resistance is inferior to when cooled at a rate of 1°C/sec or more. When the accelerated cooling material at 0.5° C./sec was subjected to a wt test using an electron microscope, intermetallic compounds rich in Cr and MO, which were thought to have been generated during rolling, were observed. Therefore, it is difficult to manufacture nickel alloy rolled clad steel sheets containing large amounts of Cr and Mo by applying processing heat treatment technology. It is desirable to develop manufacturing conditions for clad steel plates that combine high corrosion resistance of the laminate and high strength and toughness of the base material, assuming that the cladding material is subjected to rapid cooling. Therefore, we developed a component system for the base material based on the assumption of solution heat treatment at high temperatures, and based on these components, we investigated the optimal manufacturing conditions (rolling conditions and accelerated cooling conditions before solution heat treatment). . The results of the study are described below.

Figure 2 shows steel plates 1 to 10 shown in Table 1 heated to 1200°C, rolled at 1000°C, and air-cooled to 112°C.
It shows the relationship between the C content and mechanical properties of the base material when it was held at 0°C for 30 minutes and then cooled at 18°C/sec.

In the case of Nb type, Nb-V type, and Nb-Mo type, the strength is high but the toughness is poor, and it is difficult to say that the strength and toughness are well balanced. The strength decreases as the C content is lowered, and the toughness improves significantly by reducing the C content to 0.05% or less. Therefore, the amount of C needs to be 0.05% or less.

Figure 3 shows steel plates 11 to 15 shown in Table 2 heated to 1200°C, rolled at 1000°C, and air-cooled.
The relationship between the amount of Nb in the base material and the mechanical properties is shown when the sample was held at 120°C for 30 minutes and then cooled at 16°C/sec.

A structure in which the amount of Nb is less than 0.02% becomes a single phase of upper bainite, resulting in too high strength and poor toughness.

On the other hand, when the amount of Nb is increased, the strength decreases and the toughness improves up to 0.05%, but even if the amount exceeds 0.05%, the strength and toughness hardly change. Therefore,
The amount of Nb needs to be 0.02% or more and 0.05% or less.

Fig. 4 shows that steels 16 to 19 shown in Table 3 were heated to 1200°C, hot rolled, and after finishing rolling at 870°C, the air-cooled steel plates were held at 1120°C for 30 minutes, then 20°C/
The relationship between the Mn content of the base material and mechanical properties when cooled in seconds is shown.

By lowering the Mn content to 1.50% or less, the toughness improves, making it possible to manufacture a base material with a well-balanced strength and toughness. Therefore, Mn needs to be 1.50% or less.

Fig. 5 shows a case where steel 16 is heated to 1200°C, rolled at 1000°C, and then cooled in air.
If accelerated cooling is performed for 2 seconds, heating to 1200℃ and 8
In the case of air cooling after finishing rolling at 70°C, heating to 1200°C, finishing rolling at 870°C, and then heating to 480°C.
When accelerated cooling is performed at 0°C/sec, heating is performed to 1200°C, and the rolling reduction rate below 950°C is 20% and 40%.
When air-cooled after finishing rolling at ℃, heating to 1200℃ and rolling reduction ratio of 20% and 40% at 950℃ or less is 82
After finishing rolling at 0°C, accelerated cooling at 10°C/sec to 480°C was performed, and the steel plate was air-cooled to room temperature after rolling, and the steel plate was acceleratedly cooled to 1120°C after rolling.
The results of an investigation into the relationship between the rolling/cooling conditions and the mechanical properties of the base material when the material was held at 18° C. for 30 minutes and then cooled at 18° C./sec are shown. Under any rolling conditions, the toughness after high-temperature solution heat treatment is significantly improved in the accelerated cooling material compared to the air-cooling material. 95 when compared with accelerated coolant
Toughness is improved by increasing the rolling reduction below 0° C. and lowering the finishing temperature, but such rolling conditions are determined by the balance between the required toughness of the base material and the hot workability of the laminate. In addition, nickel-based alloys have high deformation resistance and low hot workability, so
If the finishing temperature was less than 700°C, the laminate would crack during rolling, so the rolling conditions were limited to a finishing temperature of 700°C or higher.

FIG. 6 shows changes in strength, toughness, and structure of the base material after high-temperature solution heat treatment when the rolling end temperature and post-rolling accelerated cooling conditions are changed. By performing accelerated cooling after rolling, the structure becomes finer and toughness is improved. This is done by making the structure as fine as possible through rolling and accelerated cooling before heat treatment, and by increasing the number of nucleation positions for austenite transformation that occurs during solution heat treatment, the number of austenite grains generated by transformation is increased.

This reduces the average grain size of austenite during solution heat treatment, suppresses the hardenability of the base material during rapid cooling after solution heat treatment, generates many fine pseudopolygonal ferrites in the structure, and improves toughness. By suppressing the occurrence of upper bainite, which causes deterioration. In particular, as in the present invention, M
For components with suppressed n, regulation by hot rolling conditions and accelerated cooling conditions is important. The heating temperature was set to 11 under rolling conditions.
The reason for setting the temperature to be 00°C or higher is that, as mentioned above, when heating at a lower temperature than that, the intermetallic compounds due to Cr and Mo will not be completely dissolved in the high Cr and high Mo composite material as in the present invention. This is because corrosion resistance is impaired. It is for the same reason that the solution heat treatment temperature is set to 1100° C. or higher. Furthermore, if the cooling rate after solution heat treatment is 1°C/sec or more, if the temperature is less than 1°C, intermetallic compounds will be generated during cooling.
This is because the corrosion resistance of the laminated material is impaired.

Based on the above, the reasons for limiting the ingredients etc. will be described below.

(1) Reason for limiting the components of the base metal■ C is required to be at least 0.020% from the perspective of ensuring strength, but as mentioned above, if it exceeds 0.050%, the upper bainite will form in the structure after solution heat treatment. Since it promotes formation and deteriorates toughness, it is necessary to keep it below o, oso%, and it is set to be 0.020% or more and o, oso% or less.

■ 0.02% or more of Si is required for deoxidation, but 1
．． If it exceeds 0%, hot workability will be significantly inhibited.
The content was 0.02% or more and 1.0% or less.

(2) Mn is required to be 0.50% or more for deoxidation and ensuring strength, but as mentioned above, if it exceeds 1.50%, toughness deteriorates, so it is set to 0.50% or more and 1.50% or less.

■ Since P deteriorates toughness, it was set to 0.02% or less.

(2) S exists mainly in the form of inclusions in steel and significantly deteriorates toughness, so it must be kept at 0.01% or less.

■ Nb forms fine Nb(C,N) together with C and N during rolling.
is precipitated to refine the ferrite grains generated in the γ→α transformation, thereby increasing the number of nucleation sites for the α→γ reverse transformation during solution heat treatment. Therefore, the number of heated γ grains per unit volume can be increased to make the average grain size finer, and the hardenability due to rapid cooling can be lowered, and the toughness of the steel sheet can be improved by changing the structure after solution heat treatment to a fine pseudoborigonal ferrite structure. It exerts an improving effect. However, as mentioned above, if it is less than 0.02%, the necessary effect cannot be obtained;
When it exceeds 0.5%, the effect of refining ferrite grains is saturated,
0.02% because the structure after solution heat treatment hardly changes and on the contrary, the toughness decreases due to an increase in precipitates.
The content was set to 0.05% or less.

■ Ti fixes N, precipitates TiN, refines ferrite grains, and improves toughness, so it needs to be at least 0,00%, but if it exceeds 0.03%, the precipitates become coarse and toughness decreases. o, oos to let
% or more and 0.03% or less.

■ Al is an element necessary as a deoxidizing agent, and its content is 0.
．． If it is less than 0.001%, it has no effect as a deoxidizing agent;
If it exceeds 6%, toughness will be inhibited, so 0.001% or more
．． 0.6% or less.

■N increases the strength by solid solution, but 0.00
If it exceeds 7%, the solid solution N becomes too high, leading to a decrease in toughness, so it is set to 0.007% or less.

In addition, the base material can also contain Cu, Ni, and MO2, and these are as follows.

@l Cu and N1 are elements that improve strength and toughness, and if it is less than 0.1%, the effect cannot be obtained, and if Cu exceeds 1.0%, hot workability will deteriorate, and if N1 is 1.
Since it is not advisable to contain more than 0% from an economical point of view, it is possible to add 0.1% or more and 1.0% or less as necessary.

(2) Mo and V are elements that stably improve the strength and toughness of the base material after solution heat treatment, and if the content is less than 0.01%, the effect cannot be obtained.

If it exceeds 0.10%, the toughness will be impaired, so 0.01%
% or more and 0.10% or less can be added as necessary.

(2) Reason for limiting the components of Cr, Mo, W, and Co in the laminated material■ Cr is an alloying element in Ni-based alloys that improves corrosion resistance in an oxidizing atmosphere, and A0 improves corrosion resistance in a reducing atmosphere. It is an element that improves. Previous proposals have suggested that Cr should be contained in a range of 0.5% to 25% and Mo should be contained in a range of 5% to 30%. In order to obtain sufficient corrosion resistance even if this atmosphere becomes the main corrosive environment, it was determined that there would be no problem as long as Mo + Cr was 225%.

(2) As mentioned above, Mo is an element that improves corrosion resistance in a reducing atmosphere, and Mo can also provide approximately the same effect. However, if it is less than 3%, no effect can be obtained, and if it is more than 10%, the disadvantages of increased cost and deterioration of processability become noticeable.
% can be selectively included in the laminate.

■ Co is an effective element for improving corrosion resistance against nitric acid, but this effect cannot be obtained unless it is contained at 0.5% or more, and if it is contained in excess of 10%, the cost increases. The effect of Zuso is saturated. Therefore, C
.

can be selectively included in the laminated material in the range of 0.5% to 10%.

(3) Effect of accelerated cooling The structure of the present invention is also characterized by accelerated cooling performed after hot rolling before heat treatment to make the structure after cooling as fine as possible. By creating such a fine structure, the number of nucleation positions for austenite transformation that occurs during solution heat treatment can be increased, and the number of austenite grains per unit volume generated by transformation can be increased. This reduces the average grain size of austenite during solution heat treatment and suppresses the hardenability of the base metal during rapid cooling after solution heat treatment.

It is possible to suppress the generation of upper bainite, which causes many fine pseudoborigonal ferrites to occur in the structure and deteriorate toughness, thereby improving toughness. Particularly in the case of ingredients that have a suppressed taste as in the present invention, regulation by accelerated cooling conditions is important. If the cooling rate after rolling is less than 5°C/sec, the structure will become a coarse ferite/pearlite structure, the heated γ grains will become coarse during solution heat treatment, and the structure after heat treatment will become a full-scale bainite structure with poor toughness. Become. Therefore, in the accelerated cooling after rolling, the cooling rate needs to be 5° C./second or more.

(4) Other heating temperature, rolling conditions, solution heat treatment conditions, heating temperature (1100°C or higher and 1250°C or lower),
Rolling conditions (finishing temperature 700°C), solution heat treatment temperature (1
(100° C. or higher and 1200° C. or lower) and cooling after the solution heat treatment (cooling rate of 1° C./sec or higher) are as described above, so they will not be particularly explained here.

[Example 1] In Table 4, clad steels were assembled in which A to G listed therein indicate the combinations of the components of the cladding material and the base material.

After heating at 1200℃ and rolling at 850℃, 500℃
It shows the results of evaluating the strength and toughness of the base material when accelerated cooling to 10°C/second was performed, followed by heating at 1120°C for 30 minutes, and then cooling at 18°C/second. The finished plate thickness is 20 mm in total, consisting of the laminated material 3cm and the base material 17++a.

The base material A is based on the specified C content of the base material, which is a feature of the present invention.
．． 05% is not satisfied, vE-46℃=0.5k
It's as low as gf-m. Base metals C and D satisfy the condition of the amount of C in the base metal, but the condition of the amount of Mn in the base material C is satisfied, and the condition of the amount of N in the base material is met.
Since the b amount condition is not satisfied, each vE-46
℃=1.3kg? m, as low as 0.3 kgf-m. On the other hand, since base material B satisfies each regulation regarding the components, it is very good at vE-46°C=40.3 kgf-m.

For clad steels E to G, Mo+Cr of the cladding material≧2
Laminated materials E and M do not satisfy the 5% regulation. The corrosion rate of laminate G which does not satisfy the stipulations (Mo+Cr≧25%) is 17.5 g/rd hr and 15.4 g/rd hr by striker test, respectively.
rn' hr, indicating low corrosion resistance. On the other hand, the laminate F, which satisfies the present invention, has a corrosion rate of 6.1.
It shows a very good value of g/rd hr.

[Example 2] Table 5 shows clad steel plates B having the combination of base material and laminated material shown in Example 1, which satisfy the compositional conditions of the present invention.

F, 20m+ (laminated material 3III) under various conditions.
11, base material 17IIN11), 30111o (laid material 7
The results of evaluating the strength and toughness of the base material when the base material was rolled into a base material (23), held at 1120°C for 30 minutes, and cooled at 18°C/sec are shown.

In Condition I, the rolling finishing temperature did not satisfy the rolling finishing temperature range of 700° C. or higher according to the present invention, so cracks occurred in the laminate. Conditions L and N do not satisfy the heating temperature range of 1100°C or more and 1250°C or less, which is the temperature range of the present invention, and condition H does not satisfy the accelerated cooling condition of the present invention. vE-46℃ is 2kg? m
Low as below. On the other hand, under conditions J, M, and ○, which satisfy the conditions of the present invention, vE-46℃ is 20kgf-+
It shows a good value of x or more.

The laminated material also exhibits high corrosion resistance.

[Example 3] Table 6 shows 12 clad steels in which a base material of low alloy steel and a composite material of nickel-based alloy are combined, the components of which are indicated from P to U.
After heating to 00℃ and finishing rolling at 870℃, 490℃
After performing accelerated cooling at a cooling rate of 13°C/sec until 11
It shows the results of evaluating the strength and toughness of the base material when it was held at 20°C for 30 minutes and cooled at 18°C/sec. The finished plate thickness is 3mm for the laminated material and 17m for the base material, totaling 20 thicknesses.

Base materials P and Q added with Mo and base materials S and T added with ■
Both of them satisfy the invention conditions of the base material, so they show good values of vE-46℃≧15kgf-Peng, but P and T show good corrosion resistance because the bonded materials do not satisfy the invention conditions. It's bad. On the other hand, R and U are low (vE-46°C≦21Cgf1) because although the laminated material satisfies the conditions of the present invention, it does not meet the regulation of the amount of C in the base material.

As mentioned above, by optimizing the component system of the base material, the rolling conditions and accelerated cooling conditions before solution heat treatment, the solution heat treatment temperature, and the cooling rate during solution heat treatment, we have created a base material with high strength and excellent toughness. We were able to establish a method for manufacturing nickel-based alloy rolled clad steel sheets with excellent corrosion resistance. In this case, in the present invention, by sandwiching Fe foil or Ni foil as an intermediate material between the base material and the laminate material, the carbon is transferred from the base material to the laminate material.
It is possible to prevent the spread of This can prevent a decrease in corrosion resistance due to carbide generated by diffusion of C into the laminate, and further improve the corrosion resistance of the laminate. In this case, one or both of Fe foil and Ni foil can be used as intermediate materials.

〔Effect of the invention〕

As described above, according to the present invention, an optimal nickel-based alloy rolled clad steel sheet can be produced by limiting the base material composition, rolling conditions before solution heat treatment, accelerated cooling conditions, solution heat treatment temperature, and cooling rate. became possible.

[Brief explanation of the drawing]

Fig. 1 is a graph showing the influence of manufacturing conditions on the corrosion resistance of the laminated material according to the present invention, Fig. 2 is a graph showing the relationship between the amount of base material C and mechanical properties (normally rolled material finished at 1000°C) according to the present invention, FIG. 3 is a graph showing the relationship between base material Nb content and mechanical properties according to the present invention (normally rolled material finished at 1000°C), and FIG. 4 is a graph showing the relationship between base material Mn content and mechanical properties according to the present invention (8
FIG. 5 is a graph showing the relationship between rolling conditions/accelerated cooling conditions and mechanical properties before solution heat treatment according to the present invention. Figure 6 shows the rolling end temperature and cooling conditions according to the present invention and TS-
It is a graph showing the relationship between vTrs and the structure after solution heat treatment. Figure 1 0 1150 1200' 1250 1120
x 30 minutes 0 heat wet 1t ('C> Figure 2 C track (\\↑Otl:. Figure 3 0 0.02 0.04 0.06Nb@j \
Het□? 6 flea Figure 4 01.0 +, 11213141.51.6 Mn amount (~
t%) Figure 5 1: Soil 11 Finishing

Claims (3)

[Claims] (1) Cr: 0.5% or more and 25% or less, Mo: in weight%
A clad steel plate laminating material in which a nickel-based alloy containing 5% or more and 30% or more and Mo+Cr≧25% is laminated on at least one side of the steel plate, C: 0.020 in weight%
% or more and 0.050% or less, Si: 0.02% or more and 1.0
% or less, Mn: 0.50% or more and 1.50% or less, P: 0
．． 02% or less, S: 0.01% or less, Nb: 0.02%
0.05% or more, Ti: 0.005% or more and 0.03
% or less, Al: 0.001% or more and 0.06% or less, N:
When rolling a clad steel plate using steel containing 0.007% or less and the balance consisting of Fe and unavoidable impurities as the base material of the clad steel plate, after heating to 1100 ° C or more and 1250 ° C or less,
Hot rolling is carried out at a finishing temperature of 700°C or higher, and after the rolling is completed, the temperature is higher than room temperature and lower than the Ar_3 transformation point of the base material.
To improve the toughness of the base material, the method comprises performing accelerated cooling at a cooling rate of 5°C/second or more, further performing solution heat treatment at a temperature of 1100°C or more and 1200°C or less, and then cooling at a rate of 1°C/second or more. A manufacturing method for superior nickel-based alloy rolled clad steel sheets. (2) The weight of the laminated material is Cr: 0.5% or more and 25% or less, Mo: 5% or more and 30% or less, and Mo+Cr≧25
%, W: 3% or more and 10% or less, Co:
The base material toughness according to claim 1, characterized in that it is a nickel-based alloy containing one or more of 0.5% to 10%, Fe: 20% or less, and the balance consists of Ni and inevitable impurities. A manufacturing method for superior nickel-based alloy rolled clad steel sheets. (3) Base material is weight%, C: 0.020% or more 0.05
0% or less, Si: 0.02% or more and 1.0% or less, Mn:
0.50% or more and 1.50% or less, P: 0.02% or less,
S: 0.01% or less, Nb: 0.02% or more 0.05%
Below, Ti: 0.005% or more and 0.03% or less, Al:
In addition to containing 0.001% or more and 0.06% or less, N: 0.007% or less, Cu: 0.1% or more and 1.0% or less, Ni: 0.1% or more and 1.0% or less, Mo: 0.01%
Claim 1 or claim 1 characterized in that the steel contains V: 0.01% or more and 0.10% or less, V: 0.01% or more and 0.10% or less, and the balance is Fe and inevitable impurities. Item 2. The method for producing a nickel-based alloy rolled clad steel plate with excellent base material toughness according to item 2.