Structural integrity and damage of ZrB2 ceramics after 4 MeV Au ions irradiation
来源期刊：JOURNAL OF MATERIALS SCIENCE TECHNOLOG2021年第13期
论文作者：Weichao Bao Stuart Robertson Jia-Wei Zhao Ji-Xuan Liu Houzheng Wu Guo-Jun Zhang Fangfang Xu
摘 要：Ultra-high temperature ceramics have been considered as good candidates for plasma facing materials due to their combination of high melting point,high strength and hardness,high thermal conductivity as well as good chemical inertness.In this study,zirconium diboride has been chosen to investigate its irradiation damage behavior.Irradiated by 4 MeV Au2+ with a total fluence of 2.5 × 1016 cm-2,zirconium diboride ceramic shows substantial resilience to irradiation-induced damage with its structural integrity well maintained but mild damage at lattice level.Grazing incident X-ray diffraction evidences no change of the hexagonal structure in the irradiated region but its lattice parameter a increased and c decreased,giving a volume shrinkage of 0.46%.Density functional theory calculation shows that such lattice shrinkage corresponds to a non-stoichiometric compound as ZrB1.97.Electron energy-loss spectroscopy in a transmission electron microscope revealed an increase of valence electrons in zirconium,suggesting boron vacancies were indeed developed by the irradiation.Alo ng the irradiation depth,long dislocations were observed inside top layer with a depth of 750 nm where the implanted Au ions reached the peak concentration.Underneath the top layer,a high density of Frank dislocations is formed by the cascade collision down to a depth of 1150 nm.All the features show the potential of ZrB2 to be used as structural material in nuclear system.
Weichao Bao1,2，Stuart Robertson3，Jia-Wei Zhao3，Ji-Xuan Liu2，Houzheng Wu3，Guo-Jun Zhang2，Fangfang Xu1
1. State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics2. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Institute of Functional Materials, Donghua University3. Department of Materials, Loughborough University
摘 要：Ultra-high temperature ceramics have been considered as good candidates for plasma facing materials due to their combination of high melting point,high strength and hardness,high thermal conductivity as well as good chemical inertness.In this study,zirconium diboride has been chosen to investigate its irradiation damage behavior.Irradiated by 4 MeV Au2+ with a total fluence of 2.5 × 1016 cm-2,zirconium diboride ceramic shows substantial resilience to irradiation-induced damage with its structural integrity well maintained but mild damage at lattice level.Grazing incident X-ray diffraction evidences no change of the hexagonal structure in the irradiated region but its lattice parameter a increased and c decreased,giving a volume shrinkage of 0.46%.Density functional theory calculation shows that such lattice shrinkage corresponds to a non-stoichiometric compound as ZrB1.97.Electron energy-loss spectroscopy in a transmission electron microscope revealed an increase of valence electrons in zirconium,suggesting boron vacancies were indeed developed by the irradiation.Alo ng the irradiation depth,long dislocations were observed inside top layer with a depth of 750 nm where the implanted Au ions reached the peak concentration.Underneath the top layer,a high density of Frank dislocations is formed by the cascade collision down to a depth of 1150 nm.All the features show the potential of ZrB2 to be used as structural material in nuclear system.
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