Crack Initiation And Propagation News Today : Breaking News, Live Updates & Top Stories | Vimarsana

White etching layers (WELs) on rail surfaces play a crucial role in dictating rail life and guaranteeing safety during transport. It has been reported that the presences of WELs correlate with wheel-rail tribological properties and rail defects, including squats and studs. It is impossible to directly measure fracture mechanisms in WELs when rails are in service because they are subject to numerous wheel passage cycles, and WELs are routinely spalled due to dynamic impact throughout their lifetime. Consequently, samples containing mechanically and thermomechanically-induced WELs, as well as WEL-free samples were sectioned from ex-service rails and subjected to three-point bending to investigate crack initiation in WELs and compare the subsequent propagation of cracks into the base material leading to fracture. The results show that WELs are subject to intergranular brittle fracture and promote ductile crack growth before macroscopic river-like cleavage failure. In contrast, the WEL-fre ....

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