Experimental and Numerical Study of Residual Stress in the WC-۱۲Co HVOF Sprayed Coatings

Thermally sprayed coatings are intrinsically associated with residual stresses in the deposits. These stresses are varied in nature and magnitude, and have a pronounced effect on the mechanical behavior of the system. In the current study, WC-۱۲Co coatings were deposited using HVOF thermal spraying. The sin۲ψ method was used to evaluate the through thickness residual stress by means of XRD after mechanical layer removal process. A nonlinear explicit-implicit finite element model was developed to study the peening and thermal stress during the high velocity impact of WC-۱۲Co particle and cooling the splat and coating layers. The average of through thickness residual stress using X-Ray diffraction and numerical model was -۱۵۷.۱ MPa and -۱۳۳.۴ MPa respectively. The results showed that the residual stress was compressive and had a good agreement with the experimental results in literature.

Keywords:

HVOF , Peening stress , FEM , WC-۱۲Co , XRD