Cladding of stellite 6 and VC powder on carbon steel using a YAG laser robot system

摘要

In the present study, a laser robot system was set up for cladding and repairing of mechanical parts using a pulsed 300W YAG laser facility, a 6-axis robot, an optical fiber of 5m in length, a powder feeding system and a special nozzle for powder supply. Stellite 6 alloy and vanadium carbide (VC) mixed powder were cladded on carbon steel (SM400B) plate. The characteristic of laser cladding of the mixed powder was investigated using the automatic system. The shape, microstructures and performances of the clad layer were investigated by changing VC volume fraction from 0% to 100%. The experimental results showed that crack susceptibility, hardness distribution, primarily solidified (V, W)C phases, and wear resistance of clad layer increased with VC volume fraction in the 0%VC ∼ 80%VC range. The microstructure can be divided into two domains of hypoeutectic and hypereutectic by changing VC volume fraction.