Microstructural features of an iron-based laser coating

摘要

A high toughness wear resistant coating is producedby laser clad Fe-Cr-W-Ni-C alloys. The microstructural andcompositional features of the laser-solidified microstructures andphase evolutions occurring during high temperature tempering at963K were investigated by using analytical electron microscopywith energy dispersive X-ray analysis. The clad coating possessesthe hypereutectic microstructure consisted of M7C3+(γ+M7C3).During high temperature aging, the precipitation of M23C6 andM2C in austenite and in situ transformation of dendritic M7C3 toM23C6 and eutectic M7C3 to M6C occurred. The laser clad coatingreveals an evident secondary hardening and superior impact wear resistance.