两类钒基合金的辐照硬化研究  

Ion-irradiation-induced hardening in alloys of V-4Cr-4Ti and V-5Cr-5Ti

作　　者：颜廷星 杨义涛[1] 马通达[3] 张崇宏[1] 范嘉琪 丁兆楠 宋银[1] 

机构地区：[1]中国科学院近代物理研究所,兰州730000 [2]中国科学院大学,北京100049 [3]北京有色金属研究总院国家有色金属及电子材料分析测试中心,北京100088

出　　处：《核技术》2017年第3期19-26,共8页Nuclear Techniques

基　　金：国家自然科学基金委大科学装置联合基金(No.U1532262);国家磁约束核聚变能研究发展计划专项(No.2011GB108003)资助~~

摘　　要：钒合金(V-Cr-Ti系列)是重要的聚变堆结构候选材料,但是相比于铁素体/马氏体钢等其他候选材料,有关钒合金(V-Cr-Ti)的辐照损伤研究较为缺乏。利用载能离子束模拟聚变堆中子辐照条件,对V-4Cr-4Ti和V-5Cr-5Ti两种样品进行了载能He离子和重离子辐照实验。实验采用离子束梯度减能方法在样品中产生辐照损伤的坪区,利用纳米压痕技术测试材料的辐照硬化效应。结果表明,样品纳米硬度的深度递减现象可以用Nix-Gao模型很好描述,高能重离子辐照的样品中软基体效应可以有效避免;在He离子辐照情形,He浓度(以原子百万分率计(Atomic parts per million,APPM))/位移损伤(以每原子平均离位数计(Displacement per atom,DPA))大于4 200/0.2时,两种钒合金样品出现硬化饱和现象;相近位移损伤水平下,He与空位的结合导致缺陷集团的加速长大,致使材料的辐照硬化远大于重离子辐照情形。Background： Vanadium alloy （V-Cr-Ti） is an important fusion reactor candidate material due to its low activation characteristics, desirable high-temperature strength and good resistance to radiation damage. However, studies at lower temperature have shown a substantially reduced radiation resistance, manifested in a loss of ductility and enhanced hardening. Purpose： This work aims to investigate the irradiation hardening behavior of vanadium alloys under He-ion implantation and displacement damage, and provide an experimental evidence for optimizing the radiation resistance of vanadium alloys. Methods： In this study, irradiation of V-4Cr-4Ti alloy and V-5Cr-5Ti alloy samples were carried out with He-ions and swift-heavy-ions. A thick layer with a uniform damage distribution in samples was produced by varying energy of He ions, or by using an energy degrade wheel for swift-heavy-ion irradiation. The nanoindentation technique was used to measure the irradiation hardening. Cross-sectional transmission electron microscopy （TEM） sample fabricated from the irradiated samples were investigated with TEM. Results： The results show that the hardening saturation occurs when the dose of He-ion implantation is more than 4 200 （Atomic parts per million, APPM）/0.2 （Displacement per atom, DPA）. The irradiation hardening by He-ions is far larger than that by the swift-heavy-ions at the same displacement damage level. Conclusion： The phenomenon of the enhanced hardening by He-ions can be attributed to the accelerated formation of defect clusters due to the combination of He-atoms and vacancies.

关 键 词：V-4Cr-4Ti V-5Cr-5Ti 辐照损伤 辐照硬化 

分 类 号：TL99[核科学技术—核技术及应用]