Many copper mould tube manufacturers are working to explore improving their service life. A single cone on the inner wall of the copper tube was first multi – cone and developed to a parabolic surface. From the copper tube raw material, from pure copper, phosphorus copper to silver copper and chromium and zirconium copper. Promote the thermal conductivity, improve the anti – deformation ability and life. However, the traditional process of hard chromium plating is used for the inner wall plating of the copper pipe. Chchrome plating has high hardness and wear resistance but thin coating with fine cracks.
Moreover, the thermal expansion coefficient of chromium varies greatly from copper. .During continuous casting, steel water penetrated into the copper surface through cracks, producing more cracks. Therefore, in the long – term corrosion of steel water, the chrome layer will be pulverized and fall off, its wear resistance is greatly reduced, the chrome coating wears out quickly in the casting process, the wear resistance of the chrome coating is limited and short life.