Effect of experimental parameters on erosive abrasive wear behaviour of cobalt based (stellite) plasma transferred arc hardfaced surface

Abstract

Material damage caused by the attack of particles entrained in a fluid system impacting on a surface at a high speed is called ‘erosive abrasive wear’. Carbon steels are the most common ones used in the fabrication and construction of boilers and furnaces. Typical erosive abrasive wear situations encountered in boilers are caused by the impact of hard particles such as ash and clinker entrained in flue gases. These situations can lead to serious damage. Engineering components encountering erosive abrasive wear conditions during operation can be improved by hardfacing with a wear resistant material. In this paper an attempt has been made to analyse in detail the effects of different experimental parameters such as specimen temperature, standoff distance, orifice diameter, air pressure and abrasive particle size on the erosive abrasive wear behaviour of cobalt based alloy (stellite) surface produced by plasma transferred arc hardfacing process. It is found that air pressure caused a predominant effect on the wear rate of a hardfaced surface, compared to other variables. Both experimental and statistical investigations show that the wear resistance of the cobalt based alloy (stellite) surface is four times better than that of the substrate (carbon steel).