Studies on sliding wear behavior of thermal spray coating and cladding on martensitic stainless steel

Abstract

The development of stainless steel material for engineering applications is in high demand. stainless steel material has good mechanical strength and acceptable resistance towards corrosion and wear. to enrich the surface properties of the stainless steel material, different surface modification techniques are adopted. in this research, an attempt is made to modify the surface with nickel and chromium based coating on martensitic stainless steel (ss 410) alloy with three different techniques. the techniques used for surface modification is as follows: atmospheric plasma spray (aps) method, tungsten inert gas (tig) cladding and metal inert gas (mig) cladding process. the modified surface is further investigated with optical microscope, electron microscope and surface hardness to identify the material behaviour. subsequently, the sliding wear behaviour of the modified surface is analysed using pin on disc (pod). as a first step, the nickel and chromium powder material is used to deposit on the stainless steel material using atmospheric plasma spray method. the coating thickness is maintained to a constant thickness of 250 and#956;m throughout the surface. the plasma spray deposit method may yield to produce some pores and voids during the material deposit. in order to control the voids and pores on the coated layer, a set of samples are post processed. a tubular furnace is used to heat treat the plasma coated samples at 900°c continuously for one hour. while post processing the coated samples, the plasma deposit reaches the austenitic state and simultaneously increases the metallurgical bonding strength. it has been confirmed through the electron microscope and found that the strength and density were increasing. in addition, the surface hardness of the plasma coating and heat treated coating is measured. the maximum surface hardness 140 newline