C. J. Li, G. J. Yang, J. C. Gao, C. X. Li, Y. Y. Wang, School of Materials Science and Engineering, Xi'an Jiaotong University, Xi'an, China
Nano-structured WC-Co coating was deposited by cold spraying using agglommerated nanostructured WC-12Co powder. The critical velocity for the particle to deposit was measured. The coating microstructure was characterized by x-ray diffraction analysis, scanning electron microscopy and transmission electromicroscopy. The coating hardness was tested by a micro-Vickers hardness tester. The deposition behavior of single nano-WC-Co particle was examined. The WC particle size was also measured for comparison of deposit properties to that of sintered bulk. The result shows that nanostructured WC-Co coating can be successfully deposited using nanostructured powders. The coating presented a dense microstructure with full retention of the original nanostructure in the powder to the coating. The test of microhardness of the coating yielded a value of over 1820Hv, which is comparable to that of sintered nanostructured WC-Co. A model was proposed for the deposition of superhard cermet materials in cold spraying.
Summary: Nano-structured WC-Co coating was deposited by cold spraying using agglommerated nanostructured WC-12Co powder. The critical velocity for the particle to deposit was measured. The coating microstructure was characterized by x-ray diffraction analysis, scanning electron microscopy and transmission electromicroscopy. The coating hardness was tested by a micro-Vickers hardness tester. The deposition behavior of single nano-WC-Co particle was examined. The WC particle size was also measured for comparison of deposit properties to that of sintered bulk. The result shows that nanostructured WC-Co coating can be successfully deposited using nanostructured powders. The coating presented a dense microstructure with full retention of the original nanostructure in the powder to the coating. The test of microhardness of the coating yielded a value of over 1820Hv, which is comparable to that of sintered nanostructured WC-Co. A model was proposed for the deposition of superhard cermet materials in cold spraying.
