Synthesis of Fe2W by low pressure laser spraying

Fe2W is the Laves type intermetallic compound with hexagonal crystal structure and is known to be a type of hard alloy. The low-pressure laser spraying (LPLS) method was applied to synthesize Fe2W clad layers on a mild steel substrate. Structure and atomic composition of surface clad layers were analyzed by X-ray diffraction and energy dispersive X-ray spectroscopy, respectively. When the substrate was exposed to a laser energy density of 36 W/mm2, the tungsten concentration of clad layers was estimated to be 20 wt.% at maximum with a microhardness of 240 Hv. The microhardness remarkably increased with heat treatment at 973 K in vacuum, suggesting that the Fe2W phase was formed with heat treatment.