Comparison of Microstructural Characteristics of Plasma and HVOF Sprayed Ni-Cr/WC Coating

In this work, Ni-Cr/WC-Co composite coating was made on SS304 substrate using Plasma and HVOF thermal spray techniques. The main objective of this work is to compare the microstructural characteristics of Ni-Cr/WC-Co coating by both the techniques, since it combines the properties, viz. hardness and toughness. The microstructure & composition of powder and coatings were characterized using Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). The coating characteristics like, micro-hardness, surface roughness and porosity were evaluated.The results show that HVOF coated samples having improved hardness over Plasma by 15% and a minimum porosity of 0.2%.