Increasing the Surface Hardness of 410 Martensitic Stainless Steel Using High Power Diode Laser

Laser surface hardening is a promising technology used for surface modification to improve the tribological properties without affecting on the bulk properties of materials. This paper surveys the capability of laser surface hardening of AISI 410 martensitic stainless steel by using continues high power diode laser with a maximum power of 1600 W, experimentally. Laser power, scanning speed and focal plane position were variable parameters in this research. The influence of process parameters on depth and width of hardened layer and microhardness profile of laser treated areas were investigated. Microstructure of the laser treated zone were studied and compared. Results show that by increasing laser power and decreasing scanning speed, higher hardness and depth achieved. Results also reveal that by decreasing in focal plane position higher depth and lower width achieved. Observations indicated that a hardened surface layer of about 1.8 mm depth and 620 HV hardness is obtained. The surface hardnening of the 410 stainless steel by diode laser is about 1.43 times the hardness of the furnace heat treatment.