Abstract
To establish the shearing delamination strength evaluation method of thin coating layer with high strength, thermal sprayed coatings were tested by newly proposed torsion pin test method with tension. In this study, delamination strength of WC-12Co thermal sprayed coating is investigated experimentally and analytically. Stress distributions at crack tip singular point on delaminated surfaces are analyzed by FEM and is approximated by the expression σ=Kr-λ where K means a size of the field of singular stress. The critical combinations of shear stress intensity factor (Ks) with tensile stress intensity factor (Ka) which means delamination criteria of coating under combined shear and tensile loadings can be obtained for various pin clearance. These combinations were found to be independent of pin clearance.
