Cold spray has been successfully used to produce WC-Co coatings in recent years, showing great potential. However, due to the lack of sufficient Co matrix phase for plastic deformation, the fabrication of cold sprayed WC-Co coating naturally requires expensive propulsive gas or very high working parameters, significantly increasing the manufacturing difficulty and cost. This paper aims to use conventional high pressure cold spray to fabricate high-performance and cost-effective WC-Co-Ni coatings, and to clarify its formation mechanism. To achieve this objective, mechanically mixed porous WC-17Co and dense Ni powders were selected as the feedstock with different WC mass fraction, F1 (41.5 wt.%), F2 (64.5 wt.%) and F3 (74.7 wt.%). Working parameters were set at a moderate level (nitrogen, 3.0MPa and 350°C) to control the experimental cost. Experimental results showed that WC reinforcements had no phase transformation and were completely retained in the WC-Co-Ni coatings. The highest WC mass fraction was present in the F3 coating, reaching approximately 75% (equivalent to the feedstock), quite close to the cold sprayed WC-25Co coating. Fracture of WC-Co particles during the deposition process was found to be the reason for such high WC retainability, dominating the coating formation mechanism.

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