Physical property effect of powder on thermal spraying coatings

WC-12Co and FeAl powders were sprayed on SUS316L stainless steel matrix by HVOF or DGS process respectively. The particle morphology, the grain size distribution and the DTA curve were investigated and the corresponding effects on the quality of spraying coatings were discussed. The results from the measurements of surface roughness and microhardness and the observations of coating morphology and X-ray diffractometry indicated that highly spheroidised and homogeneous powders lead to homogeneous microstructure, good compactness and strong bonding between the coating and the matrix. From the present experiment it can be concluded that quality of WC-12Co coating deposited by HVOF is the best, but the processing parameters of FeAl coating deposited by DGS need to be optimized further.