Residual Stresses of Plasma Sprayed ZrC-Based Coatings during Path-by-path and Layer-by-layer Deposition: Simulation and Experimental Verification

Commercial ANSYS14.5 software was used to simulate the residual stress characteristics in the deposition process of plasma sprayed ZrC-based coatings on the surface of C/C composite substrates. The simulation combined the mechanical model of composite beam adding laminate layer, and the finite element model of accumulation of path-by-path and layer-by-layer. Effects of SiC transition layer, second phase (SiC, MoSi 2 ) and coating thickness on residual stresses of the ZrC-based coatings were analyzed and validated by experiments. All results show that the SiC transition layer effectively relieve thermal mismatch stress between the coating and the substrate. Stress of the coating decreases gradually with the increase of coating thickness, which conforms to the stress relaxation and superposition law. There exist tensile stress in the coating, and compressive stress in the substrate. Moreover, compressive stress concentration is found at the interface edge, which is easly induced cracks formation and propagation along the interface. Therefor, our simulation method in present study could simulate actual spray process and predict residual stress of the coatings accurately.