Three-point bending study on the microscopic fracture behavior of pre-oxidized Cr-coated Zr-4 alloys

Abstract In this study, an in situ three-point bending test was carried out to study the mechanical properties and cracking behavior of Cr-coated Zr-4 alloy considering effect pre-oxidation. The results showed that high temperature pre-oxidation led formation intermetallic ZrCr2 at coating/substrate interface α-Zr(O) layer beneath interface. During test, Cr coating substrate good plastic deformation. However, brittle diffusion exhibited cracks early stage, which accelerated crack penetration substrate, leading pre-failure pre-oxidized sample.