Abnormal hardening effect induced by the lath-like precipitates in the V–4Cr–4Ti alloy

The present work focuses the effect of the precipitate's shape on the hardness of V–4Cr–4Ti alloy. It is found that there are numerous lath-like Ti-rich precipitates occurring in the samples subjected to different heat treatment. The habit plane of these precipitates is the {200} plane of the matrix. The distribution density of the precipitates is closely related to heating temperatures and times. The hardness valley of the samples occurs at the heating temperatures corresponding to the high distribution density of precipitates. The abnormal hardening effect can be interpreted by a model, in term of which lath-like precipitates with high distribution density result in single gliding of dislocations and reduced work-hardening. •Abnormal precipitation hardening in the V–4Cr–4Ti alloy was investigated.•Hardness valley corresponds to the high distribution density of the precipitates.•Interfaces between the precipitates and matrix is coherent.