Effect of Grinding Parameters on the Fracture Toughness of WC–10Co–4Cr Coating Deposited by HVOF

Document Type : Original Article


1 Institute of Materials and Energy, Iranian Space Research Center, Isfahan, Iran

2 Department of Mechanical Engineering, Tarbiat Modares University,Tehran, Iran

3 Department of Material Engineering, Isfahan University of Technology, Isfahan, Iran


Nowadays, application of cermet coatings deposited by High-Velocity Oxygen-Fuel (HVOF) has received considerable attention in a variety of industries. Carbide coatings have high surface roughness, so it is essential to grind the coated surface. The present investigation studied the effect of simultaneous changes in the grinding parameters including the depth of cut, feed rate and cutting speed on the fracture toughness of the WC-10Co-4Cr coating sprayed by HVOF. The fracture toughness was measured using the Vickers Indentation Test on the cross-sectional surface of the coating. A full factorial design of experiment was selected for experimental planning and the analysis of variance was employed to find the effect value of grinding parameters on output. The results revealed that the fracture toughness of the WC-10Co-4Cr coating increases after grinding due to the higher compressive residual stresses. The fracture toughness of coating increases with the decrease of the cutting speed and the increase of the depth of cut and feed rate. The most effective grinding parameters are depth of cut, feed rate and cutting speed, respectively. At the end of the current study, a mathematical model between grinding parameters and the fracture toughness of the coating was proposed using the regression analysis.


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