This paper introduces the preparation method of metal
composite panels (2)
2. Explosive billet-rolling method
The explosive billet-rolling method is a production method of the required base and clad material after explosive welding, and then rolling to the clad strip of the required specification and size through a hot rolling mill. This method is a new combined technology developed by synthesizing the respective advantages of explosive composite technology and rolling technology. Its advantages are:
(1) The billet made by the explosive composite method ensures the quality of the bonding area of the two-layer or three-layer metal clad plate;
(2) The product has high dimensional accuracy and good surface quality;
(3) Increase the flexibility of production and facilitate promotion.
3. Sintering method
The sintering method is a composite method in which powder particles and a composite substrate are combined with each other by heating in a protective atmosphere. The protective gases are mainly hydrogen and nitrogen. The composite substrate needs to be pretreated by degreasing, rust removal and roughening. There are two main methods of powder preparation:
(1) Mix the powders of dissimilar pure metals uniformly;
(2) The powder of the cladding alloy is directly prepared. The basic principle of the sintering method is that at high temperature, the atomic amplitude increases and diffusion occurs, so that dissimilar metal atoms form a bond. It is mainly used in the composite of composite substrate and alloy cladding. Since in the sintering process, the sintering temperature is lower than the melting point of the high melting point pure metal component, so the microstructure and properties of the alloy coating are very uniform, which is a beneficial supplement to the rolling method.
4. Casting and rolling composite method
The process of the casting-rolling composite method is as follows: two steel plates are superimposed, the inner layer is coated with a stripping agent, and then placed in a casting mold filled with molten metal after welding around them. After the liquid metal solidifies, preliminary rolling is performed, and the welded The edge is cut off to obtain a composite board. High composite strength can be achieved under appropriate temperature and pressure. The method is simple in process and low in cost, and can be used for mass production.
5. Reverse solidification method
The reverse solidification process is a thin strip continuous casting process developed by German metallurgists in 1989. The process is to let a certain thickness of base strip pass through the molten steel in the reverse solidifier, so that the molten steel near the surface of the base strip is rapidly cooled, solidified on the surface of the base strip to form a new phase, and rolling is carried out when the new phase is still in a semi-solidified state , to obtain a hot-rolled thin strip with a smooth surface and a uniform thickness. This method is a new fusion technology for producing bimetallic composites. However, it is different from the mold casting method. The substrate is ordinary carbon steel (solid phase), and the composite layer is stainless steel (liquid steel). It has the characteristics of high efficiency and low energy consumption. It can produce composite panels with stainless steel composite layers less than 1mm. It can realize the continuous and short flow of the production process, the process is simple, the product quality is high, and it is beneficial to environmental protection.
6. Electromagnetic continuous casting compound method
The electromagnetic continuous casting method for producing composite panels is still in the research stage. The basic principle is: two molten steels with different chemical compositions are injected into the mold through different immersion nozzles at the same time. Since the horizontal magnetic field is installed at the lower part of the mold, the Lorent magnetic force acting on the steel flow vertically passes through the horizontal magnetic field. The mixing of the two molten steels is suppressed, and the horizontal magnetic field becomes a dividing line, and the molten pool of the mold is divided into upper and lower parts by the action of the magnetic fluid force. Through the cooling effect of the mold, the molten steel in the upper molten pool solidifies into the outer layer of the composite billet, and the molten steel in the lower molten pool solidifies inside the outer shell to form the inner core of the billet.
Advantages of this method:
(1) Since the composite of stainless steel and other steel materials is directly realized in the mold, the oxidation and slag inclusion of the bonding interface can be avoided;
(2) Because of the liquid-liquid phase combination, compared with the reverse solidification method, the interface bonding strength of the produced stainless steel clad plate is higher, and there is no need to activate the surface of the substrate;
(3) No pollution, suitable for mass production.
