HVOF Spraying Process Optimization for the Deposition of Submicron Structural WC-12Co Coatings

Abstract:

The submicron structural WC-12Co coatings were deposited by a high-velocity oxy-fuel (HVOF) system from agglomerated WC-12Co powders with carbide grain size of 0.7~0.9μm in this study. Effects of HVOF spraying parameters on the microstructure and properties of submicron structural WC-12Co coatings were examined. The results showed that both the fuel flow rate and spraying distance influenced significantly the microhardness and porosity of coatings, and cooling condition also had a few effect on the porosity of coatings. Through a series of experiments, the spraying parameters for the WC-12Co coatings preparation were optimized as follows: propane gas pressure was 0.65 MPa, propane flow rate of 16.7 L/min, oxygen pressure of 0.7 MPa, oxygen flow rate of 100 L/min, spraying distance of 270 mm and with compressed air cooling. The porosity of WC-12Co coating sprayed at the optimum parameters was lower than 1%, and its microhardness was HV_0.1 1141±67.

• Periodical: Advanced Materials Research (Volumes 785-786)
• Pages: 839-843
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.785-786.839
• Online since: September 2013
• Authors: Ning Ma, Zhen Xiong Cheng, Huan Tao Wu, Fu Xing Ye
• Keywords: HVOF, Process Optimization, Submicron Structure, WC-12Co

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