X射线源用靶材表面的缺陷分析

ANALYSIS OF DEFECT ON THE SURFACE OF THE TARGET FOR X-RAY SOURCE

钨钼及其合金因具有良好的导热、导电、高温强度和耐磨等特性,成为电子电力、金属材料等航天工业应用的重要材料,钨钼靶材是产生X射线的重要组成部件,被广泛应用于医学和材料等领域,其质量对使用性能至关重要。靶材生产过程中,其工作表面常常伴随“龟裂”缺陷,严重影响了产成品的合格率。本实验采用扫描电镜、显微硬度和光学显微镜等分析方法对钨钼靶材工作表面的裂纹缺陷进行微观分析。结果表明:靶材表面裂纹缺陷微观视野下表现为“龟状裂纹”现象,其内部不含有杂质元素,龟裂缺陷附近区域的晶粒细小、硬度高,龟裂较远区域的晶粒粗大且硬度小,龟裂缺陷产生的主要工序是磨削过程中摩擦热和高能机械力共同导致。本文确定了靶材工作表面“龟裂纹”缺陷的来源,对实际生产和研究机构具有非常重要的现实意义。

Tungsten and molybdenum and their alloys have become important materials for aerospace industry applications such as electronic power and metal materials due to their good thermal conductivity,electrical conductivity,high temperature strength and wear resistance.Tungsten and molybdenum targets are important components for X-ray generation and are widely used in medical and material fields.Their quality is crucial to their performance.In the process of target production,its working surface is often accompanied by“crack”defects,which seriously affects the qualified rate of finished products.In this experiment,scanning electron microscope,microhardness and optical microscope were used to analyze the crack defects on the working surface of tungsten-molybdenum target.The results show that the surface crack defect of the target is a“turtle-shaped crack”phenomenon in the microscopic view,which does not contain impurity elements inside.The grain near the crack defect is fine and has high hardness,while the grain far from the crack defect is coarse and has low hardness.The main process of the crack defect is caused by friction heat and high-energy mechanical force in the grinding process.This article determines the source of the target“crack”defect,which has very important practical significance for actual production and research institutions.