Determination of Grinding Process Effect on the Through Thickness Residual Stress in HVOF-deposited WC–10Co–4Cr coating

Application of WC-10Co-4Cr coating deposited by High Velocity Oxygen Fuel (HVOF) has been significantly developed in key parts of various industries, nowadays. These coatings are ground to achieve the desired surface roughness. In this study, the residual stress of as-sprayed and ground coating was determined by the X-ray diffraction (XRD) technique using sin2 method and finite element method(FEM). In the experimental evaluation, the chemical layer removal process was used to measure the through thickness residual stress. In the finite element analysis of the grinding process, the temperature distribution of workpiece is initially obtained by applying the thermal flux from the grinding process. Then the workpiece cools until it reaches the ambient temperature. The temperature history of thermal analysis is applied to the stress analysis and the final distribution of residual stress is determined by applying grinding forces and residual stress caused by the HVOF process. The results showed that there was a good agreement between the experimental and simulation results and after the grinding process, the value of compressive residual stress of coating surface increases was increased. Also, in the experimental and simulation investigation, the increase in compressive residual stress compared with the pre-grinding was up to 100 μm and 120 μm, respectively. There is no increase in compressive residual stress in the higher depth of coating and also in the interface of the coating and substrate.