HARD SURFACING OF AUSTENITIC STAINLESS STEEL BY THERMAL SPRAYING OF POWDER

Abstract

In this work hard surfacing of austenitic stainless steel has been carried out by thermal spraying process using nickel based alloy powder and oxyacetylene gas regulated to give natural flame. During the hard surfacing preheating of substrate material is varied to 200°C, 250°C and 300°C. After hard surfacing some of the samples are given a post spray heat treatment at temperature 600°C, 750°C and 900°C for 2 hrs soaking in muffle furnace. The geometry of hard surface coating produced under different preheating are studied. The effect of no post spray heating and post spray heating at different temperature on the microstructures of the coating and interface with substrate are studied. The effect of post spray heating at different temperatures on the hardness of coating obtained under different preheating are investigated. The wear property and cumulative volume loss of the coating is measured and correlated the post spray heat treatment of the coating obtained under preheating of 200°C.