Research On The Performance And Process Of Laser Cladding Layer Based Of Co Base Alloy

Laser cladding is an advanced surface modification technology, which can cladding a layer of high performance coating in a lower cost base material surface, in order to improve the material on the surface of high temperature resistance, wear resistance,oxidation resistance and other properties. Cobalt powder’s comprehensive performance is good, and its laser cladding coating has excellent wear resistance, corrosion resistance,and it also can maintain a higher hardness and wear resistance especially under the condition of high temperature. In this article, the WC powder/TZ303 cobalt base alloy powder that resistant the high temperature and wear was compounded, the optimal process parameters was determined by the test and its microstructure and properties are analyzed,.The main contents are as follows:The WC powder/TZ303 cobalt base alloy powder that resistant the high temperature and wear was compounded. By high power semiconductor laser, the process parameters test on WC/TZ303 cobalt base alloy powder has been done, the optimal process parameters combination was determined, the laser cladding layer of WC/TZ303 cobalt base alloy powder was prepared and the influence of the process parameters on morphology of laser cladding layer was analyzed. At the same time, Stellite6 cobalt base alloy powder laser cladding layer which was commonly used in the market was prepared.In the macro aspect, the quality of two kinds of alloy cladding was carried on the comparative analysis, and two types of cladding layer both had a bright metallic luster, but relative to the WC/TZ303 cobalt base alloy cladding layer, Stellite6 cobalt base alloy cladding layer surface had a small amount of porosity and micro cracks, and it was less flat than the WC/TZ303 cobalt base alloy cladding layer’s surface on the whole. When using high power semiconductor laser for cladding, Al2O3 can’t reduce the macroscopic defects of the cladding surface of Stellite6 cobalt base alloy.The microstructure and mechanical properties of two kinds of cladding layer were comparative analyzed and the experimental results showed that: the tensile properties and toughness of Stellite6 cobalt base alloy powder cladding layer was slightly better than thatof the WC/TZ303 cobalt base alloy powder laser cladding layer; microstructure of Stellite6 cobalt base alloy powder was more bulky compared with that of WC/TZ303 cobalt base alloy powder, and the hole defects was obvious; the hardness and wear resistance of WC/TZ303 cobalt base alloy powder laser cladding layer are obviously better than that of Stellite6 cobalt base alloy powder. But as the WC/TZ303 cobalt base alloy powder containing WC particles, the toughness of the cladding layer would be slightly down when improved the hardness and wear resistance of the cladding layer.Using the WC/TZ303 cobalt base alloy powder, the repair and remanufacturing research on the damaged rollers were done. The optimal process parameters that cladding WC/TZ303 cobalt base alloy powder in the rollers surface were determined and the test plan was developed. The research on testing and performance of rollers after cladding were done and the results showed that the rollers surface had no micro crack, and the hardness and wear resistance of the repaired rollers surface both met the requirements of remanufacturing.