Finite element simulation of thermal stress in RF magnetron sputtered SiC coating as tritium penetration barrier

Abstract

The magnitude of thermal stress in the tritium penetration barrier coating is crucial during RF (radio frequency) magnetron sputtering preparation. The thermal stress would cause the delamination or crack on the coating, which seriously affects the structural stability of the coating. In this work, a finite element model represented the SiC tritium penetration barrier coating system was established. The relevant parameters which affected the magnitude of thermal stress of the system were discussed in detail. The shear and radial stresses in the system were also evaluated in order to identify the locations where the materials were prone to failure. Then, the propagation of multiple surface cracks in the system was investigated. Finally, the thermal stress was optimized by an Al2O3 interlayer. The outcomes indicated that the addition of the Al2O3 interlayer alleviated the stress at the interface and enhanced the mechanical stability and adhesive strength of the coating.