[SY-C12] Symposium C-12

[SY-C12] The effect of microscopic slip deformation on the yield stress in dispersion hardened alloys analyzed by using crystal plasticity FEM

^○Yelm Okuyama¹, Masaki Tanaka¹, Tatsuya Morikawa¹, Tetsuya Ohashi² (1.Dept. of Materials Science and Engineering, Kyushu University, Japan, 2.Dept. of Engineering, Kitami Institute of Technology, Japan)

The relationship between yield stress and the distribution of microscopic plastic deformation was investigated in dispersion hardened alloys using crystal plasticity FEM. Dispersed particles were randomly distributed in a 3D box in the calculation model. A plate region was extracted from the 3D box, and was used as a finite element model. The length factor in the Orowan equation was determined form the particle distribution in the 3D box. The critical resolved shear stress in local was set to a function of the length factor in the model. The length factor was defined as the average spacing of the particles, which surround the element, on the slip plane. The crystal plasticity analysis elucidates that the initiation and propagation of local slip deformation depends on the length factor. In this study, the relationship between the length factor and macroscopic mechanical response, i.e. yield stress and work hardening rate, is discussed.