Bimetal composite steel belt and manufacturing method thereof

Abstract

The invention discloses a bimetal composite steel strip which comprises a steel substrate and a coating, the steel substrate is made of high-strength carbon steel, the thickness of the steel substrate is 10-60 mm, the coating is made of stainless steel, the thickness of the coating is 5-8 mm, and the steel substrate and the coating are combined through explosive welding. According to the bimetal composite steel strip and the manufacturing method thereof, the high-strength carbon steel base body is combined with the stainless steel coating, the high-strength characteristic of the steel base body is reserved, large mechanical force can be borne, the good corrosion resistance of the stainless steel coating is achieved, erosion of various corrosive media can be effectively resisted, and the service life of the bimetal composite steel strip is prolonged. The application range of the steel belt is greatly widened, and the steel belt can be suitable for various complex and severe industrial environments; and an explosive welding process is adopted, and the detonation velocity TNT explosive is increased through a detonator for detonation, so that the problems of layering and the like of the steel substrate and the coating are avoided, and the integrity of the material is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of steel strip manufacturing, and in particular to a bimetallic composite steel strip and a manufacturing method thereof. Background Art

[0002] In modern industry, especially in the chemical industry, marine engineering, food processing and other industries, the performance requirements for metal materials are becoming increasingly stringent. On the one hand, the material needs to have high strength to withstand large mechanical loads, pressure and impact forces, and ensure the stability and safety of the structure under complex working conditions; on the other hand, good corrosion resistance is also essential, because these industries are often faced with erosion by various corrosive media, such as acid, alkali, salt solution and humid marine environment.

[0003] Traditional single metal materials are difficult to meet the dual requirements of high strength and high corrosion resistance at the same time. For example, although carbon steel has high strength and relatively low cost, it is easy to rust and corrode in corrosive environments, resulting in a shortened service life, increased maintenance costs, and potential safety hazards caused by corrosion, such as leakage accidents caused by corrosion in chemical pipelines. Although stainless steel has excellent corrosion resistance, its strength is lower than that of carbon steel. In order to overcome the limitations of single metal materials, bimetallic composite materials came into being. By combining metal materials with different properties, the advantages of each layer of metal can be fully utilized to achieve an optimized combination of material properties.

[0004] The traditional manufacturing process of the existing bimetallic composite steel strip is raw material steel strip-edge trimming-welding-annealing-weld flattening-leveling and straightening, but the existing bimetallic composite steel production efficiency is not high. During welding, welding is a process of rapid cooling after heating, and the material will expand and contract with heat. The two metal materials are different, and the expansion coefficients are also different. Therefore, the steel strip will have severe sickle bend after welding, and it is difficult to ensure that the welding material is flush, which often causes the steel strip to be severely twisted during welding. This distortion will be retained after the subsequent annealing treatment, and eventually cause the deformation of the bimetallic composite steel strip. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the present invention provides a bimetallic composite steel strip and a method for manufacturing the same, the purpose of which is to solve the problem that the traditional manufacturing process of the existing bimetallic composite steel strip is raw material steel strip-edge trimming-welding-annealing-weld flattening-leveling and straightening, but the existing bimetallic composite steel production efficiency is not high. During welding, welding is a process of rapid cooling after heating, and the material will expand and contract with heat. The two metal materials are different, and the expansion coefficients are also different. Therefore, the steel strip after welding will have serious sickle bends, and it is difficult to ensure that the welding material is flush, which often causes the steel strip to be severely twisted during welding. This distortion will be retained after the subsequent annealing treatment, and eventually cause deformation and other problems of the bimetallic composite steel strip.

[0006] In order to achieve the above-mentioned object of the invention, the technical solution adopted by the present invention is:

[0007] A bimetallic composite steel strip comprises a steel substrate and a coating, wherein the steel substrate is made of high-strength carbon steel with a thickness of 10-60 mm, the coating is made of stainless steel with a thickness of 5-8 mm, and the steel substrate and the coating are bonded by explosion welding.

[0008] Furthermore, the steel matrix is ​​one of Q345B carbon steel, 65Mn high carbon steel and 60Si2MnA high carbon steel.

[0009] Furthermore, the coating is one of 316L, 310S, Cr25Mo3Ti and Cr28 stainless steel.

[0010] A bimetallic composite steel strip and a method for manufacturing the same, comprising the following steps:

[0011] S1: Steel substrate and cladding treatment: Use metal sheet cleaning equipment to clean both sides of the steel substrate and the cladding surface to be composited, until there are no pits, wrinkles, oxides and oil stains on the surface of the composited plate, and then set aside;

[0012] S2: Place the treated coating surface to be bonded on both sides of the steel substrate;

[0013] S3: Explosive welding, in which detonators and high-detonation-velocity TNT explosives are used for detonation; first one side of the coating is explosively welded, and then the other side of the coating is explosively welded;

[0014] S4: Use ultrasonic flaw detector to detect flaws, the bonding rate between steel substrate and coating shall not be less than 99%;

[0015] S5: heating the composite steel plate and sending it to a hot rolling mill to be rolled into a steel strip;

[0016] S6: Inspect the steel strips and use a straightening machine to finish the steel strips that meet the requirements.

[0017] Furthermore, in step S3, the explosion welding comprises the following steps:

[0018] S31: First, prepare the foundation for explosion welding, place the steel substrate on a flat foundation, with one side of the steel substrate facing upward;

[0019] S32: Use copper sheet to make a fulcrum with a height of 12mm-18mm, place one side of the steel substrate on the fulcrum, and there is a gap of 12mm-18mm between the coating and one side of the steel substrate;

[0020] S33: Explosives are placed on the coating and ignited, causing the steel substrate and coating to collide at high speed and be explosively welded together;

[0021] S34: After the coating is explosively welded on one side of the steel substrate, the coating on the other side is explosively welded on the other side of the steel substrate using the same method and steps.

[0022] Furthermore, in step S33, explosives with a stable detonation velocity between 2000m / s-2300m / s, uniform density, and not prone to agglomeration are used;

[0023] Furthermore, in step S5, the rolled thickness of the composite steel strip is not greater than 4 mm.

[0024] Furthermore, in step S31, the foundation is a level foundation of a sandy soil structure.

[0025] Furthermore, in step S5, the composite steel plate is heated to 1250±10° C. and kept warm in the furnace for 2.5 hours to 3 hours.

[0026] Furthermore, in step S6, the straightening machine is used for finishing twice, and the unevenness is detected on the inspection platform to be less than 1 mm / m.

[0027] The beneficial effects of the present invention are:

[0028] The bimetallic composite steel strip and the manufacturing method thereof of the present invention combine a high-strength carbon steel substrate with a stainless steel coating, thereby retaining the high-strength characteristics of the steel substrate and being able to withstand greater mechanical forces, and having the good corrosion resistance of the coating stainless steel, and being able to effectively resist the erosion of various corrosive media, thereby greatly broadening the application scope of the steel strip and being applicable to a variety of complex and harsh industrial environments; an explosive welding process is adopted, and detonation is performed by using a detonator with a high-explosion velocity TNT detonating explosive, so that the steel substrate and the coating will not have problems such as stratification, thereby ensuring the integrity of the material. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the explosion structure of the bimetallic composite steel strip of the present invention;

[0030] Figure 2This is a manufacturing flow chart of the bimetallic composite steel strip of the present invention.

[0031] Reference table of reference numerals:

[0032] 1. Steel substrate; 2. Coating. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention are described clearly and completely below.

[0034] The object of the present invention is to provide a bimetallic composite steel strip having excellent performance and a method for manufacturing the same, wherein the composite steel strip has not only good corrosion resistance and strength, but also good toughness and machinability.

[0035] like Figure 1 As shown, the bimetallic composite steel strip of the present invention mainly includes two parts, namely a steel substrate 1 and a coating 2. The steel substrate 1 is made of high-strength carbon steel with a thickness ranging from 10 to 60 mm and has strong tensile and compressive resistance.

[0036] The coating 2 is made of stainless steel with a thickness ranging from 5 to 8 mm and has strong oxidation resistance and corrosion resistance.

[0037] In order to improve the bonding performance between the steel substrate 1 and the coating 2, the manufacturing method of the present invention adopts an explosive welding method. By controlling the detonation velocity and density of the explosive and adopting reasonable welding parameters, the steel substrate 1 and the coating 2 can be tightly bonded together, thereby forming a bimetallic composite steel strip that has both the high strength characteristics of steel and the good corrosion resistance of stainless steel.

[0038] like Figure 2 As shown, the bimetallic composite steel strip and the manufacturing method thereof of the present invention comprise the following steps:

[0039] S1: Select 65Mn high carbon steel with a thickness of 30mm as the steel substrate 1, and 316L stainless steel with a thickness of 4mm as the cladding 2. The steel substrate 1 and the cladding 2 are processed, and the metal sheet cleaning equipment is used to clean the two sides of the steel substrate 1 and the surface of the cladding 2 to be composited, respectively, until there are no pits, wrinkles, oxides and oil stains on the surface of the composite board, and then set aside;

[0040] S2: placing the treated coating 2 to be bonded on both sides of the steel substrate 1;

[0041] S3: Explosive welding, during which a detonator with high detonation velocity TNT detonating explosive is used for detonation; firstly, one side of the coating 2 is explosively welded, and then the other side of the coating 2 is explosively welded;

[0042] S31: First, a foundation for explosion welding is prepared, and the steel substrate 1 is placed on a flat foundation, which is a flat foundation of sand structure, with one side of the steel substrate 1 facing upward;

[0043] S32: A fulcrum with a height of 12 mm to 18 mm is made of copper sheet, and one side of the steel substrate 1 is placed on the fulcrum, with a gap of 12 mm to 18 mm between the coating 2 and one side of the steel substrate 1;

[0044] S33: Explosives are placed on the coating 2, and the explosives are ignited and detonated by using the explosives with a stable detonation velocity between 2000m / s-2300m / s, uniform density, and not easy to agglomerate. The steel substrate 1 and the coating 2 are explosively welded together through high-speed collision;

[0045] S34: After the coating 2 is explosion-welded on one side of the steel substrate 1, the coating 2 on the other side is explosion-welded on the other side of the steel substrate 1 using the same method and steps.

[0046] S4: Use ultrasonic flaw detector to detect flaws, and the bonding rate between steel substrate 1 and coating 2 is not less than 99%;

[0047] S5: heating the composite steel plate to 1250±10℃, keeping it in the furnace for 2.5 hours to 3 hours, and sending it to the hot rolling mill to be rolled into a steel strip, the rolled thickness of the composite steel strip is not more than 4mm;

[0048] S6: Inspect the steel strips, use a straightening machine to straighten the steel strips that meet the requirements twice, and check their unevenness on the inspection platform to be <1mm / m.

[0049] The bimetallic composite steel strip and its manufacturing method of the present invention adopt explosive welding. Through the explosive welding process, the steel substrate 1 and the cladding 2 can be tightly combined together during high-speed collision. The explosive welding can not only achieve high-strength and high-quality metallurgical bonding, but also avoid the heat-affected zone and residual stress problems that may be caused by traditional welding methods, thereby achieving efficient welding effects.

[0050] The bimetallic composite steel strip and its manufacturing method of the present invention, by combining a high-strength carbon steel substrate 1 with a stainless steel coating 2, retain the high-strength characteristics of the steel substrate 1 and be able to withstand greater mechanical forces, and also have the good corrosion resistance of the stainless steel coating 2, which can effectively resist the erosion of various corrosive media, greatly broadening the application range of the steel strip and making it suitable for a variety of complex and harsh industrial environments.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A bimetallic composite steel strip, characterized in that: It comprises a steel substrate and a coating, wherein the steel substrate is made of high-strength carbon steel with a thickness of 10-60 mm, the coating is made of stainless steel with a thickness of 5-8 mm, and the steel substrate and the coating are combined by explosion welding.

2. A bimetallic composite steel strip according to claim 1, characterized in that: The steel matrix is ​​one of Q345B carbon steel, 65Mn high carbon steel and 60Si2MnA high carbon steel.

3. The bimetallic composite steel strip according to claim 1, characterized in that: The coating is one of 316L, 310S, Cr25Mo3Ti and Cr28 stainless steel.

4. A bimetallic composite steel strip and a method for manufacturing the same, comprising a bimetallic composite steel strip according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1: Steel substrate and cladding treatment: Use metal sheet cleaning equipment to clean both sides of the steel substrate and the cladding surface to be composited, until there are no pits, wrinkles, oxides and oil stains on the surface of the composited plate, and then set aside; S2: Place the treated coating surface to be bonded on both sides of the steel substrate; S3: Explosive welding, in which detonators and high-detonation-velocity TNT explosives are used for detonation; first one side of the coating is explosively welded, and then the other side of the coating is explosively welded; S4: Use ultrasonic flaw detector to detect flaws, the bonding rate between steel substrate and coating shall not be less than 99%; S5: heating the composite steel plate and sending it to a hot rolling mill to be rolled into a steel strip; S6: Inspect the steel strips and use a straightening machine to finish the steel strips that meet the requirements.

5. A bimetallic composite steel strip and a method for manufacturing the same according to claim 4, characterized in that: In step S3, the explosion welding comprises the following steps: S31: First, prepare the foundation for explosion welding, place the steel substrate on a flat foundation, with one side of the steel substrate facing upward; S32: Use copper sheet to make a fulcrum with a height of 12mm-18mm, place one side of the steel substrate on the fulcrum, and there is a gap of 12mm-18mm between the coating and one side of the steel substrate; S33: Explosives are placed on the coating and ignited, causing the steel substrate and coating to collide at high speed and be explosively welded together; S34: After the coating is explosively welded on one side of the steel substrate, the coating on the other side is explosively welded on the other side of the steel substrate using the same method and steps.

6. A bimetallic composite steel strip and a method for manufacturing the same according to claim 5, characterized in that: In the step S33, explosives with a stable detonation velocity between 2000m / s and 2300m / s, uniform density and not prone to agglomeration are used.

7. The bimetallic composite steel strip and the method for manufacturing the same according to claim 4, characterized in that: In step S5, the rolled thickness of the composite steel strip is not greater than 4 mm.

8. The bimetallic composite steel strip and the method for manufacturing the same according to claim 5, characterized in that: In the step S31, the foundation is a flat foundation of sand structure.

9. The bimetallic composite steel strip and the method for manufacturing the same according to claim 4, characterized in that: In the step S5, the composite steel plate is heated to 1250±10° C. and kept in the furnace for 2.5 to 3 hours.

10. A bimetallic composite steel strip and a method for manufacturing the same according to claim 4, characterized in that: In step S6, the straightening machine is used for finishing twice, and the unevenness is detected on the inspection platform to be less than 1 mm / m.

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