Study of early stage surface evolution of molybdenum coated tungsten bombarded by helium plasma

doi:10.16568/j.0254-6086.202002008

Abstract

Abstract:

The sample of molybdenum coated tungsten (Mo-W) has been prepared by magnetron sputtering to investigate the process of fuzz formation as well as the physical mechanism. The surface morphology evolution of W, Mo blocks and Mo-W sample under the 773K or 1073K temperature plasma treatment and the action of helium plasma were observed by using various microstructure characterization methods. The results show that the behaviors of surface evolution of Mo, W and Mo-W samples under the action of helium plasma are almost the same, and the fuzz and coral-like precursor grow from the cone-like structures having relative larger dimension.

Key words: Molybdenum-tungsten sample, Magnetron sputtering, Fuzz, Cone-like structure, Helium bubble

摘要：

为了研究纳米绒毛的生成过程及内在的物理机制，采用磁控溅射镀膜的方式在钨片上镀有钼涂层 (Mo-W)。借助微观结构观察的手段分析了钨、钼块材以及钨-钼(Mo-W)样品在773K、1073K氦等离子体作用条件下的表面形貌演变过程。结果表明：钨、钼以及钨-钼(Mo-W)样品在氦等离子体作用下表面形貌演变规律基本一致；纳米绒毛及其珊瑚状前驱体是在尺寸相对较大的锥状结构上演化而来的。

关键词: 钨-钼样品, 磁控溅射, 纳米绒毛, 锥状结构, 氦泡

CLC Number:

TL62+1

QIAN Wei, ZHENG Peng-fei, WANG Lian, XU Li-sha,LIU Xing, WEI Ran, BAI Quan, CHE Tong. Study of early stage surface evolution of molybdenum coated tungsten bombarded by helium plasma[J]. NUCLEAR FUSION AND PLASMA PHYSICS, 2020, 40(2): 142-147.

钱伟，郑鹏飞，王炼，徐丽莎，刘星，魏然，白泉，车通. 含钼涂层钨材料在氦等离子体作用下的前期表面形貌演变研究[J]. 核聚变与等离子体物理, 2020, 40(2): 142-147.

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