Hardening effect of multi-energyW2+-ion irradiation on tungsten–potassium alloy

作     者：Yang-Yi-Peng Song Wen-Bin Qiu Long-Qing Chen Xiao-Liang Yang Hao Deng Chang-Song Liu Kun Zhang Jun Tang 宋阳一鹏;邱文彬;陈龙庆;杨晓亮;邓浩;刘长松;张坤;唐军

作者机构：Key Laboratory of Radiation Physics and Technology of Ministry of EducationInstitute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China Key Laboratory of Materials PhysicsInstitute of Solid State PhysicsChinese Academy of SciencesHefei 230031China 

出 版 物：《Chinese Physics B》 (中国物理B（英文版）)

年 卷 期：2020年第29卷第10期

页      面：363-369页

核心收录：

学科分类：08[工学] 082701[工学-核能科学与工程] 0827[工学-核科学与技术] 

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11975160 and 11775149) supported by the Fundamental Research Funds for the Central Universities,China 

主　　题：plasma facing material tungsten-potassium alloy ion-irradiation hardening nanoindentation 

摘      要：Tungsten is one of the most promising plasma-facing materials (PFMs) to be used in the nuclear fusion reactor as divertor material in the future. In this work, W2+-ions bombardment is used to simulate the neutron irradiation damage to commercial pure tungsten (W) and rolled tungsten–potassium (W–K). The 7 MeV of 3 × 10^15 W2+-ions/cm2, 3 MeV of 4.5 × 10^14 W2+, and 2 MeV of 3 × 10^14 W2+-ions/cm2 are applied at 923 K in sequence to produce a uniform region of 100 nm–400 nm beneath the sample surface with the maximum damage value of 11.5 dpa. Nanoindentation is used to inspect the changes in hardness and elastic modulus after self-ion irradiation. Irradiation hardening occurred in both materials. The irradiation hardening of rolled W–K is affected by two factors: one is the absorption of vacancies and interstitial atoms by potassium bubbles, and the other is the interaction between potassium bubbles and dislocations. Under the condition of 11.5 dpa, the capability of defect absorption can reach a threshold. As a result, dislocations finally dominate the hardening of rolled W–K. Specific features of dislocation loops in W–K are further observed by transmission electron microscopy (TEM) to explain the hardening effect. This work might provide valuable enlightenment for W–K alloy as a promising plasma facing material candidate.