Open AccessThe dual role of martensitic transformation in fatigue crack growth
Author(s) -
Xiaogang Wang,
Chenghuan Liu,
Binhan Sun,
Dirk Ponge,
Chao Jiang,
Dierk Raabe
Publication year - 2022
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2110139119
Subject(s) - materials science , paris' law , crack closure , martensite , coalescence (physics) , diffusionless transformation , brittleness , microstructure , austenite , fracture mechanics , fatigue testing , metallurgy , structural engineering , composite material , engineering , physics , astrobiology
Significance About 90% of all mechanical service failures are caused by fatigue. Avoiding fatigue failure requires addressing the wide knowledge gap regarding the micromechanical processes governing damage under cyclic loading, which may be fundamentally different from that under static loading. This is particularly true for deformation-induced martensitic transformation (DIMT), one of the most common strengthening mechanisms for alloys. Here, we identify two antagonistic mechanisms mediated by martensitic transformation during the fatigue process through in situ observations and demonstrate the dual role of DIMT in fatigue crack growth and its strong crack-size dependence. Our findings open up avenues for designing fatigue-resistant alloys through optimal use of DIMT. They also enable the development of physically based lifetime prediction models with higher fidelity.