报告题目：Radiation response of nanoporous and nanotwinned metals
Xinghang Zhang obtained his Ph.D. from North Carolina State University in 2001. After postdoctoral experience at Los Alamos National Laboratory, he joined Texas A&M University as an assistant professor in 2005 and was promoted to full professor in 2015. He joined Purdue University as a professor in 2016. Zhang’s team excels at radiation damage and mechanical behavior of nanocrystalline, nanotwinned, and nanolayered metals. He has published more than 180 journal articles with more than 6,000 citations. He has delivered numerous invited talks internationally. Among more than 20 of his Ph.D. students so far, 4 have become professors at university and many others are at US national laboratories. He was the Chair of the Chemistry and Physics of Materials Committee at the TMS (Metals, Minerals and Materials Society). Zhang has received numerous research awards, including National Science Foundation’s Early Career award (2007), TEES Fellow award (2013), and College of Engineering Holleran-Bowman Faculty Fellow award (2014). Zhang can be reached at email@example.com.
Severe high energy particle (neutron) and ion irradiation environment can introduce significant microstructural damage and consequent degradation of mechanical properties in irradiated metallic materials. It remains a scientific challenge to design advanced radiation tolerant materials. Numerous approaches have been applied to alleviate radiation damage. Here we will present some recent studies on enhanced radiation tolerance of nanostructured metallic materials, in particular nanoporous and nanotwinned metals. In situ heavy ion irradiation studies reveal direct evidence of defect-free surface interactions in nanoporous metals. Meanwhile high density twin boundaries prominently reduce the density of radiation induced defect clusters in nanotwinned Ag and Cu compared with their bulk counterparts. Defect migration kinetics (diffusivity of defect clusters) was compared between coarse grained and nanoporous metals. These studies provide insight towards understanding on the role of free surface and twin boundaries on alleviation of radiation damage in metallic materials.