Abstract: Nanostructure and conventional WC-12Co feedstock powders were thermally sprayed via high velocity oxy-fuel (HVOF) on the substrate of 16Mn.Phases of the feedstock powders and the coatings were analyzed by XRD.The characterizations of spraying powders,microstructure and surface morphology of the prophase and anaphase attrition surfaces were analyzed by SEM.The influence of structure of feedstock powders and spraying parameter on melt and decomposition of WC during spraying and the structure of coatings and abrasive wear resistance properties were investigated.The results indicate that the conventional WC particles do not decompose obviously during spraying,while nanostructured WC decompose partly,which resulted in weight loss of abrasive wear of nanostructured WC-12Co coating is less slightly than conventional WC-12Co coating,but the two kinds of coatings both display the super properties of the abrasive wear resistance properties compare to 16Mn.