微观组织对叠片结构钨基面向等离子体材料的热疲劳效应的影响  

Influence of microstructure on thermal fatigue effect of laminated tungsten based plasma-facing material

作　　者：祁超[1] 马玉田[2] 齐艳飞 肖善曲 王波[1] Qi Chao;Ma Yu-Tian;Qi Yan-Fei;Xiao Shan-Qu;Wang Bo(College of Materials Science and Engineering,Beijing University of Technology,Beijing 100124,China;Institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,China;College of Metallurgy and Energy,North China University of Science and Technology,Tangshan 063210,China)

机构地区：[1]北京工业大学材制学部,北京100124 [2]中国科学院电工研究所,北京100190 [3]华北理工大学冶金与能源学院,唐山063210

出　　处：《物理学报》2024年第11期101-109,共9页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:52104374);中央引导地方科技发展资金项目(批准号:236Z1004G)资助的课题。

摘　　要：钨(W)作为面向等离子体材料的最佳候选者,对热冲击载荷的响应是未来聚变装置研究中的重要问题.在热负荷作用下,钨基面向等离子体材料(W-based plasma-facing material,W-PFM)的表面会产生热损伤,包括脆性开裂和疲劳裂纹.本文提出了抑制W-PFM热损伤的新方案,即叠片结构W-PFM方案.利用电子束设备对不同厚度和热处理工艺的W箔组成的叠片结构W进行了热疲劳实验.样品施加功率密度为48 MW/m^(2)的热脉冲,循环5000次.随着W箔片厚度的减小,叠片结构W表面的裂纹损伤减轻.叠片结构W在循环热载荷作用后表面产生的主裂纹均近似平行于箔片厚度方向.厚度较小的W箔表面只有主裂纹,厚度较大的W箔表面除了出现主裂纹外,还会形成裂纹网络,且主裂纹宽度较大.最终选取热损伤区域的扫描电子显微镜图像,并利用计算机图片处理软件和分析软件,对表面热疲劳裂纹损伤进行了定量分析.发现相同厚度下应力态W的裂纹面积最小,裂纹数量最少,说明去应力态W的抗辐照损伤能力最强.实验结果还表明,除了微观组织的影响,叠片结构W-PFM的单轴应力状态和裂纹阻断机制也都对其热疲劳性能的提高有所贡献.The response of tungsten(W)to thermal shock loading,as the best candidate for plasma-facing material(PFM),is an important issue in the research of future fusion devices.Under thermal loading,thermal irradiation damage,including brittle cracking and fatigue cracking,occurs on the surface of tungsten based plasma-facing material(W-PFM).In this work,a new scheme to suppress the thermal irradiation damage to W-PFM,i.e.the laminated structure W-PFM scheme,is proposed.Thermal fatigue experiments of laminated structure W composed of W foils with different thickness and heat treatment processes are carried out by using an electron beam device.The samples are subjected to thermal pulses with a power density of 48 MW/m^(2) for 5000 cycles.The results indicate that the crack damage to the surface of the laminated structure W decreases with the decrease of the thickness of Wfoils under the same heat treatment conditions.The main cracks are produced on the surface of laminated structure W after cyclic thermal loads have been all approximately parallel to the foil thickness direction.Only the main cracks appear on the surfaces of W foils with a smaller thickness,while crack networks develop on the surfaces of Wfoils with a larger thickness,in addition to the main cracks with a larger width.In the rolled state,the laminated structure Whas the lowest degree of surface plastic deformation for the same thickness.The thermal fatigue crack damage to the surface is quantitatively analyzed by using computer image processing software and analysis software,and scanning electron microscope images of the thermal damage area are finally selected.It is found that the de-stressed state Whas the smallest crack area and the smallest number of cracks for the same thickness,indicating that the de-stressed state Whas the strongest resistance to irradiation damage.The experimental results also show that in addition to the effect of microstructure,both the uniaxial stress state and the crack-blocking mechanism of the laminated structured W-PFM cont

关 键 词：聚变 面向等离子体材料 钨 热疲劳 

分 类 号：TG1[金属学及工艺—金属学]