Design and application of stainless steel clad plate in engineering

Knowledge / 2020-07-07 10:25:45

The stainless steel composite plate is a composite plate steel plate formed by combining a carbon steel base layer and a stainless steel coating. Its main feature is that carbon steel and stainless steel form a strong metallurgical combination, which can perform various processes such as hot pressing, cold bending, cutting, and welding, and has good process performance. For the base material of the stainless steel composite board, various common carbon steels and special steels such as Q235B, Q245R, Q345B, and Q345R can be used. The cladding material can use 304, 316L, 321 and duplex stainless steel and other stainless steels. Material and thickness can be freely combined to meet the needs of different users. Stainless steel composite panels have been widely used in petroleum, chemical, salt industry, water conservancy and power industries. As a resource-saving product, stainless steel clad plate reduces the consumption of precious metals and greatly reduces the project cost. Realizing the perfect combination of low cost and high performance has good social benefits.
 
How is the stainless steel composite board produced?
 
There are two main methods for industrial production of stainless steel composite panels, explosive composite and hot-rolled composite. The production process of the explosive composite board is to put the stainless steel plates on the carbon steel substrate overlapping, and the stainless steel plate and the carbon steel substrate are separated by a certain distance with a cushion. The explosives are tiled on the stainless steel plate, and the energy of the explosive explosion causes the stainless steel plate to hit the carbon steel substrate at high speed, generating high temperature and high pressure to realize the solid phase welding of the interface of the two materials. Under ideal conditions, the shear strength per square millimeter of the interface can reach 400MPa. The process of hot-rolled composite plate is made by rolling carbon steel substrate and stainless steel plate in a physically pure state under high vacuum conditions. During the rolling process, the two metals diffuse to achieve complete metallurgical bonding. Of course, in order to improve the wetting effect of the composite interface and improve the bonding strength, a series of technical measures must be taken in the physical and chemical treatment of the interface. The above two composite board manufacturing methods implement the GB/T-8165-1977 national standard, which is not equivalent to the Japanese JISG3601-1990 standard, and the main technical indicators are the same or higher than the Japanese standard.
 
So what are the process characteristics of explosive composite and hot-rolled composite panels?
 
Let me talk about the characteristics of explosive recombination:
1. Because explosive compounding is cold working, it can produce many kinds of metal compound panels except stainless steel compound panels, such as titanium, copper, aluminum and so on.
2. Explosive recombination can produce stainless steel composite plates with a total thickness of several hundred millimeters, such as some large bases and tube plates. However, it is not suitable for the production of thinner composite steel plates with a total thickness of less than 10 mm.
3. Explosive compound production using the energy of explosives will cause vibration, noise and smoke pollution to the environment. However, equipment investment is low, and there are hundreds of domestic explosion production plants. Due to the limitation of weather and other technological conditions, the explosive compound production efficiency is low.
 
Besides, the characteristics of the hot rolling composite process:
1. Large-scale medium plate rolling mill and hot continuous rolling mill are used for production, so the production efficiency is high and the delivery speed is fast. The product has large format and free combination of thickness. The thickness of stainless steel coating can be produced above 0.5mm. But the investment is large, so there are fewer manufacturers.
2. Due to the limitation of the compression ratio of the rolled steel, hot rolling production cannot produce composite steel plates with a thickness of more than 50mm, and it is also inconvenient to produce various small batches, round and other special shapes of composite plates. The advantages of hot rolled composite plates are 6. 8. 10mm thin specification composite board. Under the condition of hot continuous rolling, it can produce composite coils, reduce production costs, and meet the needs of more users.
3. Under the current technical conditions, the hot rolling process cannot directly produce nonferrous metal composite plates such as titanium, copper, and aluminum.
 
In summary, the two very different production processes have their own characteristics, and they exist and develop at the same time to meet the diverse needs of different users. The explosive rolling method is a combination of the foregoing two processes and will not be described in detail.
 
The stainless steel composite board has the characteristics of various carbon steels and stainless steels, and is welcomed by users with its excellent performance-price ratio, and has a broad market prospect. But what is interesting is that since the 1950s, after more than half a century of ups and downs in the development process, there are still many people who do not know it, and more people have not used it. It should be said that the market for stainless steel composite panels is far from maturity and is still in the process of development. The exploration and efforts of science and technology workers for building a resource-saving society will never stop.

Design and application of stainless steel clad plate in engineering