Corrosion, adhesion and erosion study of MZ and ML system using thermal plasma

Abstract

Mullite processed through thermal plasma has been identified as promising material in ceramic industry for thermal barrier coating (TBC) applications. Addition of ZrO2 as impurities reduces the fracture toughness property of mullite coatings. In the current study, effort has been taken to compare the performance of La2O3 as an equivalent material to ZrO2. Here MZ (Mullite-ZrO2) and ML composites (Mullite-La2O3) have been prepared in different weight proportions of 10%, 20% and 30%. The MZ and ML composites are ball milled for 2 hr and sprayed over AISI 1045 steel specimen at 15 cm and 20 cm spray distance using 15kW thermal plasma torch. The MZ and ML coated samples were studied for SEM, XRD, adhesion test, roughness, wear, sliding test and coating thickness. Though the ML material has not been tested for exact application, but the study reveals that La2O3 can be used as cost effective material for TBC applications.