Numerical investigation of fracture behavior of nanostructured metals with bimodal grain size distribution
Xiang Guo (Tianjin University), Xunyang Dai (School of Mechanical Engineering, Tianjin University, Tianjin 300072, China), Linli Zhu (Zhejiang University), Jian Lu (City University of Hong Kong)
Prager Medal Symposium in honor of George Weng: Micromechanics, Composites and Multifunctional Materials
Mon 4:20 - 5:40
MacMillan 117
Nanostructured metals with bimodal grain size distribution (coarse and nanosize grains) have been proved to have high strength and good ductility. In this paper, numerical simulations based on Johnson-Cook fracture model investigate effects of (i) distribution characteristics of the coarse grains and (ii) constitutive relationship of the nanosize grains with different grain sizes on fracture behavior in the center-cracked-tension specimen of the bimodal copper. Simulations in high strain rate show that both of them have large influences on the load response and energy history, and importantly, they are closely related to characteristics of the pre-crack propagation.