The effect of sealing on the wear behaviour of plasma sprayed Mo coating

Abstract

Plasma sprayed molybdenum coating thickness of 300 µm was deposited on steel substrate. Electro deposition of nickel has been used to fill the open pores and micro cracks of the plasma sprayed molybdenum coating. The quantitative investigation of porosity was carried out with image analysing software. The microhardness was measured using a Vickers' indenter. The influence of sealing on wear resistance of plasma prayed molybdenum was estimated by using pin on disk wear test rig. The worn surface was characterised by scanning electron microscopy. The experimental results indicated that porosity of coating was decreased and microhardness was increased by sealing. It is concluded that electro deposition of Ni is a promising sealing treatment for sprayed coating. In this study, sealed plasma sprayed coating consisting of lowest porosity, the higher hardness and better wear resistance.