Deposition-induced residual stresses in plasma-sprayed coatings

Coupled heat transfer and elastic–plastic finite element analyses were conducted to study thermal stress generation and development during deposition of a nickel–cobalt (NiCoCrAlY) alloy on an aluminum disc (AA1100) substrate. A general purpose commercial finite element method (FEM) software ANSYS was used for the simulation of the temperature as well as stress and strain histories during the deposition process. A FEM special software feature called the element birth and death was used. The stress built-up during spraying was experimentally obtained by means of deflection measurement. A close agreement between the numerically predicted deflected shapes of the specimen and the experimental results indicated that the stress–strain distributions from the numerical elastic–plastic model could be applied with reasonable accuracy.