Improvement of wear resistance of Hastelloy C-276 through laser surface melting

The Hastelloy C-276 was laser surface treated in argon atmosphere to improve the tribological properties. The influence of laser power and scan speed on the metallurgical and mechanical properties are evaluated. The laser treated zone generally consists of coarse dendrites when treated with low laser power which transformed into fine equiaxed grains at optimum power and scan speed combination. The cooling rate found to be more influential than the thermal gradient in determining the microstructural features. An improvement in hardness of 447 HV0.3 was observed in the laser treated zone which yielded an improvement in wear resistance up to four factors. The absence of elemental segregation or new alloy formation after laser surface treatment confirmed the preservation of inherited bulk properties, a vital characteristic to extend the application in tribocorrosion.

► High degree of grain refinement was achieved under optimum laser treatment conditions.
► The hardness of Hastelloy C-276 was improved up to 447 HV0.3 which resulted in improved wear resistance.
► The laser treatment did not affect the inherent corrosion properties of the material.
► The proposed method could extend the application of Hastelloy C-276 in tribocorrosion environment.