中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 28 No. 3 March 2018 |
（1. State Key Laboratory of Advanced Technology for Materials and Processing, Wuhan University of Technology, Wuhan 430070, China; 2. School of Energy and Power Engineering, Wuhan University of Technology, Wuhan 430063, China）
Abstract:A new kind of multi-dimensional WC-10Co4Cr coating which is composed of nano, submicron, micron WC grains and CoCr alloy, was developed by high velocity oxy-fuel (HVOF) spraying. Porosity, microhardness, fracture toughness and cavitation erosion resistance of the multi-dimensional coating were investigated in comparison with the bimodal and nanostructured WC-10Co4Cr coatings. Moreover, the cavitation erosion behavior and mechanism of the multi-dimensional coating were explored. Results show that HVOF sprayed multi-dimensional WC-10Co4Cr coating possesses low porosity (≤0.32%) and high fracture toughness without obvious nano WC decarburization during spraying. Furthermore, it is discovered that the multi-dimensional WC-10Co4Cr coating exhibits the best cavitation erosion resistance which is enhanced by approximately 28% and 34%, respectively, compared with the nanostructured and bimodal coatings in fresh water. The superior cavitation resistance of multi-dimensional WC-10Co4Cr coating may originate from the unique micro-nano structure and excellent properties, which can effectively obstruct the formation and propagation of cavitation erosion cracks.
Key words: WC-10Co4Cr; cavitation erosion; multi-dimensional coating; high velocity oxy-fuel (HVOF) spraying; microstructure
