Comparative investigation of HVOF and flame sprayed CoMoCrSi coating

Abstract

Present studies deals with comparison of high velocity oxy fuel and flame spray coating process by developing CoMoCrSi (Tribaloy T400) coating on a titanium grade-15 substrate. Prior to coating, feedstock is processed to obtain higher fraction intermetallics through high energy ball milling technique under controlled atmosphere. Processed feedstock material is sprayed on a Ti-15 substrate through HVOF and Flame spray process. The coated specimens are subjected to metallurgical and mechanical characterization using optical microscope, scanning electron microscope, energy dispersive spectroscopy, x-ray diffraction, Vickers mico hardness tester and bond strength using pull off test method. HVOF sprayed coating exhibits superior properties compared to Flame sprayed coating in terms of surface roughness, porosity, micro hardness and adhesion strength. The detailed studies of two coating systems is discussed. © 2020 Author(s).