journal article·2021-08Open access

Crack initiation mechanisms under two stress ratios up to very-high-cycle fatigue regime for a selective laser melted Ti-6Al-4V

Leiming Du, Xiangnan Pan, Guian Qian, Liang Zheng, Youshi Hong

Abstract

Abstract Crack initiation mechanisms under two stress ratios (R = − 1 and 0.5) and up to very-high-cycle fatigue (VHCF) regime of a selective laser melted (SLMed) Ti-6Al-4V were investigated. Type I lack-of-fusion defects (almost equiaxed) induced crack initiation except for the cases of VHCF under R = 0.5 in which type II defects (large aspect ratio) caused facet mode crack initiation. A nanograin layer formed underneath the crack initiation region of rough area for the cases of VHCF at R = − 1, which was explained by the numerous cyclic pressing (NCP) model. A P-S-N approach was introduced to well describe the fatigue life up to VHCF regime under R = − 1 and 0.5 for the SLMed titanium alloy.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Additive Manufacturing Materials and Processes · Welding Techniques and Residual Stresses · High Entropy Alloys Studies

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

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