Significant improvement in fatigue life of titanium alloy induced by superlattice coating

The purpose of this paper is to investigate the effect of the TiN coating and the TiN/AlN superlattice coating on the fatigue performance of titanium alloys. The effect of the coating on the fatigue property of the titanium alloy is studied through the coating-substrate interaction. The results show that the TiN/AlN superlattice coating with high hardness and fracture toughness inhibits strain localization on the surface, changes the location of fatigue crack initiation and improves the fatigue strength at 10(7) cycles by 23.7%. Dislocation redistribution and secondary slip are found in the titanium alloy to eliminate stress concentration.

Automated summary

The purpose of this paper is to examine the impact of TiN coating and TiN/AlN superlattice coating on the fatigue performance of titanium alloys. The study focuses on the interaction between the coating and the substrate to understand the influence of the coating on the fatigue properties of titanium alloys. The results demonstrate that the TiN/AlN superlattice coating, which possesses high hardness and fracture toughness, effectively suppresses strain localization on the surface, alters the initiation site of fatigue cracks, and enhances the fatigue strength by 23.7% at 10^7 cycles. Dislocation redistribution and secondary slip in the titanium alloys were observed as mechanisms to eliminate stress concentration.