| Prediction of Fatigue Crack Initiation in Magnesium Alloys Manabu Enoki1; Fabien Briffod1; Takayuki Shiraiwa1; 1THE UNIVERSITY OF TOKYO, Bunkyo-ku, Japan; PAPER: 294/Magnesium/Invited (Oral) SCHEDULED: 12:10/Fri. 25 Oct. 2019/Adonis ABSTRACT: Magnesium (Mg) and its alloys have received particular interest, especially in the automotive industry, for potential lightweight structural applications due to their low density and high specific strength. Most Mg alloys, however, suffer from poor mechanical properties at ambient and elevated temperatures. They also lack strong plastic anisotropy due to the low-symmetry of the hexagonal crystal structure. The strength of heterogeneity of the different deformation mechanisms and the thermo-mechanical processes often lead to strong crystallographic textures. Synthetic microstructures generated from statistical data obtained from EBSD measurements was generated based on a developed approach, and numerical simulations based on the Crystal Plasticity Finite Element Method (CPFEM) were also proposed [1, 2]. Crystal plasticity which takes into account the dislocation slip and twinning is considered and fitted against experimental cyclic stress-strain hysteresis curves. Fatigue simulations are conducted with different loading conditions to quantify and correlate the local plastic strain with the crack initiation sites observed experimentally in various Mg alloys, including LPSO-Mg. References: [1] F. Briffod, T. Shiraiwa, M. Enoki, Materials Science and Engineering A, 695 (2017), 165-177. [2] Briffod, T. Shiraiwa, M. Enoki, Materials Science and Engineering A, 753 (2019), 79-90. |
