Laser coating and 3D printing of Co-based alloys

Co-based alloys have extensive applications as hard phase, anti-corrosion and anti-wearing coating, and biocompatible implanting components. However, it is technical challenging for coating and machining due to high melting points and hardness. Conventional high velocity oxy-fuel (HVOF) thermal spraying processes and additive manufacturing are prone to form cracks due to large temperature gradients and residual stress. In this work, we reported laser coating and 3D printing of Co-based alloys with air-spray micro sized powders onto stainless steel base materials. Two kinds of laser are compared with continue wave fiber laser and femtosecond pulsed laser. The microstructure and mechanical properties as well as anti-corrosion properties are characterized.