Vacuum electron beam welding group billet hot rolling to produce stainless steel clad plate
The layered metal composite board not only has the characteristics of the cladding material, including the properties of corrosion resistance, heat resistance, and abrasion resistance, but also has the characteristics of the base material, such as strength and rigidity, and is a new type of material. Among them, stainless steel clad plate is the most widely used metal clad plate, accounting for more than 80%. It uses corrosion-resistant, heat-resistant, and wear-resistant stainless steel as the cladding, and uses carbon steel or low-alloy steel with relatively high strength and better plastic toughness as the base layer. The material and thickness can be freely combined.
Compared with pure stainless steel, stainless steel clad plate has obvious performance and cost advantages, which can save 70-80% of alloy elements such as Cr and Ni, which can save 30-50% of the cost. Not only can it greatly save stainless steel materials, but also significantly reduce The material cost of various equipment and structural parts. As a resource-saving product, it can be widely used in petroleum, chemical, salt, water conservancy, and electric power industries, greatly reducing engineering costs, realizing the perfect combination of low cost and high performance, and having good economic benefits.
At present, the industrial production of stainless steel clad plates mainly adopts explosive compounding, explosive compounding + rolling, and rolling compounding processes. The domestic production of stainless steel clad plates is mainly based on explosive composite and explosive composite + rolling methods. However, with the development of science and technology, the requirements for composite panels are getting higher and higher, especially with the enhancement of environmental protection awareness, the disadvantages of explosive composites have gradually attracted people’s attention.
First of all, the thickness range of the multi-layer used in the explosive process is limited, and a good combination cannot be achieved if it is too thick or too thin; at the same time, its continuity is not strong, the degree of automation is low, and the efficiency is low. Work hardening occurs on the bonding surface, so it needs to be softened after the explosion. In addition, a specific explosion site is also required.
Although explosive technology has been widely used in the United States, Japan, and other developed countries, the vibration and noise caused by the explosion are difficult to control. Due to the above shortcomings of the explosive compounding method and the explosive compounding + rolling process, people are eager to develop a new type of High-efficiency, environmentally-friendly stainless steel composite panel production process.
In this context, scholars at home and abroad have gradually turned their attention to the rolling composite plate technology. With the development of equipment in the direction of large-scale, high-speed, and continuous, hot-rolling technology can be used to produce various composite panels with high efficiency, high quality, and low cost, especially composite panels with a panel width exceeding 3000 mm that cannot be produced by explosive technology. , Compared with the explosive process, it has significant advantages. As the rolling technology continues to mature, in addition to special materials, the explosive process is gradually replaced by the rolling process.
The technical staff of a company used vacuum electron beam welding technology to carry out the rolling test of the stainless steel clad plate through the hot rolling process and tested the stainless steel clad plate shape, bonding surface structure, tensile, impact, shear, and bending properties. The inspection and analysis were carried out, and the technical characteristics of the hot-rolled stainless steel clad plate of the vacuum electron beam welding group billet were discussed. The results showed that:
(1) Adopting vacuum electron beam welding and hot-rolling production process to build blanks under vacuum conditions, improve the bonding ability and performance of the interface, and obtain 304/Q235B stainless steel composite plates with good plate shape and uniform thickness control.
(2) The obtained 1/6mm specification 304/Q235B stainless steel clad plate has no gaps on the joint surface, and various mechanical properties are good. Among them, the shear strength is 450MPa, which is much higher than the 2100MPa required by the national standard for stainless steel clad plate, and reaches the R1 level. standard.
(3) Through shear fracture observation and energy spectrum analysis, it is determined that the shear specimen of the 304/Q235B stainless steel clad plate is a ductile fracture, and the fracture position is on the Q235B side, indicating that the carbon steel side is the weak area of the stainless steel clad plate. (Yu Ye)