What are the options for the plating of copper plate of crystal accessoriesIn order to increase the wear resistance of copper plate of crystal accessories, a
What are the options for the plating of copper plate of crystal accessories
In order to increase the wear resistance of copper plate of crystal accessories, a variety of surface coating methods are adopted. At the same time, various different coatings can be selected according to different types, which can play the role of adaptation, better protect the surface and prolong the service time.
Copper plating of crystallizer accessories:
1. Cr plating. At the initial stage of coating research, Cr coating was adopted based on the friction resistance and splash resistance of the mold. A very thin layer of oxide film formed on the surface of Cr is very beneficial to the splash generated during pouring and the falling off of molten steel particles after solidification. However, when the coating is thick, it is easy to peel off. A coating with a thickness of about 0.06 ~ 0.10mm can be used.
2. Ni + Cr composite coating. In order to solve the coating thickness, Ni + Cr composite coating is adopted. Since the thermal expansion coefficient of Ni is close to that of Cu, the stripping problem is greatly improved and the thickness is increased. Ni solves the problems of adhesion and thickness, and Cr solves the problems of splashability and surface hardness. In order to solve the problem of poor Ni thermal conductivity, the inclined layer process is introduced. The thickness of Ni layer at the meniscus can be controlled at about 0.2mm and that at the outlet can be controlled at about 3mm.
3. Ni Fe coating. When Fe or W and Fe are added to Ni, the hardness of the coating is significantly improved. Ni Fe coating was first developed by Nomura Gold Plating Co., Ltd. in Japan and named tap coating. It has the following characteristics: the hardness can be adjusted in the range of hv250 ~ 550 according to different Fe content.
4. Copper plate coating of crystallizer accessories: Ni Co coating and Co Ni coating. In order to further improve the wear resistance of the coating and improve the service life of mold copper plate, Ni Co coating and Co Ni coating have been developed abroad. These are actually two kinds of superalloys with different substrates. Ni Co is a nickel base alloy containing cobalt and Co Ni is a cobalt base alloy containing nickel.
shengmiao
Harm of too high temperature: when molten steel out of cooper mold, the billet shell is thin and easy to break out; The accelerated erosion of refractory can ea
shengmiao
1. The barrier function (mainly completed by the liquid slag layer) isolates the contact between air and molten steel, blocks the secondary oxidation of molten
shengmiao
In continuous casting, low corrosion resistance often occurs, which directly leads to uneven composition and will eventually affect the smelting quality. In or