Dry linear reciprocating wear behavior of molybdenum-reinforced SS316 laser claddings deposited by laser directed energy deposition

Abstract

This study aims to improve the wear resistance and extend the service life of AISI 304 stainless steel, which is extensively used in marine impellers, chemical reactors, and industrial mixers. The improvement is achieved using Laser Directed Energy Deposition (LDED) cladding of molybdenum-reinforced SS316 powders onto AISI 304 stainless steel. Dry linear reciprocating wear experiments were conducted on the claddings of SS316 and Mo (10 and 20 wt%) reinforced SS316 at ambient temperature under varying normal loads of 10 N and 20 N. The worn scar was examined using a 3D non-contacting profilometer. Microstructure and wear mechanism were analyzed using Field emission scanning electron microscopy (FE-SEM). The micro-hardness test revealed that the hardness of SS316 + 20% Mo claddings was nearly 1.10 and 1.41 times higher than that of SS316 + 10% Mo, and SS316 claddings respectively. The study also revealed that SS316 + 20% Mo Cladding provides better wear resistance and lower Coefficient of Friction (CoF) compared to SS316 + 10% Mo and SS316 claddings, due to the formation of the hard carbide phases like MoC and Fe2C during LDED process. The wear analysis indicated the presence of both abrasive and adhesive wear mechanisms, especially under higher load conditions. At a 20 N load, the SS316 + 20% Mo cladding demonstrated a 2.55-fold reduction in wear rate compared to SS316.

Keywords

• Laser directed energy deposition (LDED)
• Laser cladding
• Linear reciprocating wear
• Carbide phases.