H. Zhao, Z. Ding, Y. Zhang, Wuhan University of Technology, Wuhan, China
Nanostructured and conventional WC-12Co coatings were deposited by HVOF and the properties of the coatings such as microhardness, microstructure, erosion and adhesive wear resistance were compared. Finally the failure mechanisms of wear of WC-12Co coatings were explored by SEM analysis. Research results show: 1) Microstructures of nanostructured WC-12Co coatings deposited by HVOF are dense and possess little porosity; 2) Microhardness of nanostrutured WC-12Co coatings is obviously higher than conventional WC-12Co coatings; 3) Nanostructured WC-12Co coatings exhibit more excellent erosion wear resistance in comparison with conventional coating. At 30º and 90º the erosion wear performance of the nanostructured coatings is enhanced respectively by about 70% and 65%; 4) At small impact angles WC-12Co coatings deposited by HVOF demonstrate better erosion wear resistance than at large impact angles and the erosion wear performance at 30º is 2 times as high as at 90º; 5) In comparison with conventional HVOF WC-12Co coating, the adhesive wear resistance of the nanostructured coating is higher about 60%.
Summary: Research results show: 1) Microstructures of nanostructured WC-12Co coatings deposited by HVOF are dense and possess little porosity; 2) Microhardness of nanostrutured WC-12Co coatings is obviously higher than conventional WC-12Co coatings; 3) Nanostructured WC-12Co coatings exhibit more excellent erosion wear resistance in comparison with conventional coating. At 30º and 90º the erosion wear performance of the nanostructured coatings is enhanced respectively by about 70% and 65%; 4) At small impact angles WC-12Co coatings deposited by HVOF demonstrate better erosion wear resistance than at large impact angles and the erosion wear performance at 30º is 2 times as high as at 90º; 5) In comparison with conventional HVOF WC-12Co coating, the adhesive wear resistance of the nanostructured coating is higher about 60%.
