光学元件亚表层裂纹成核临界条件研究

发布时间：2018-01-17 18:34

本文关键词：光学元件亚表层裂纹成核临界条件研究　出处：《强激光与粒子束》2016年04期 　论文类型：期刊论文

【摘要】：基于压痕实验和连续刚度测量法得到了熔石英材料硬度和弹性模量随压入深度的变化曲线,系统分析了材料由延性到脆性转变的过程,确定了熔石英晶体在静态/准静态印压和动态刻划时产生裂纹的临界载荷和临界深度。渐变载荷刻划实验结果表明,划痕过程诱发的裂纹对法向载荷有很强的依赖性,载荷较小时材料去除方式为延性域去除。随着法向载荷的增加,首先产生垂直于试件表面的中位裂纹和平行于试件表面方向扩展的侧向裂纹,而在试件表面上并没有产生明显的特征。载荷进一步增加后,侧向裂纹扩展并形成了明亮区域,最终诱发了沿垂直于或近似垂直于压头运动方向扩展的径向裂纹,实现了材料的脆性去除。
[Abstract]:Based on indentation test and continuous stiffness measurement, the variation curves of hardness and elastic modulus with indentation depth were obtained, and the process of material transition from ductility to brittleness was analyzed systematically. The critical load and critical depth of crack produced by static / quasi-static indentation and dynamic scratching of fused quartz crystal are determined. The crack induced by scratch process is strongly dependent on the normal load, and the material removal mode is ductile domain when the load is small, and with the increase of normal load. First, the median crack perpendicular to the surface of the specimen and the lateral crack propagating parallel to the surface of the specimen are generated, but there is no obvious characteristic on the surface of the specimen. The lateral crack propagates and forms a bright region, which eventually induces radial cracks propagating perpendicular to or approximately perpendicular to the movement of the head, thus achieving brittleness removal of the material.
【作者单位】：哈尔滨工业大学机电工程学院;中国工程物理研究院激光聚变研究中心;
【基金】：国家自然科学基金项目(51475106) 国家自然科学基金委员会-中国工程物理研究院联合基金项目(U1230110) 中国工程物理研究院超精密加工技术重点实验室开放基金项目(KF14007)
【分类号】：O346.1
【正文快照】： 光学元件磨粒加工过程可以抽象为尖锐或钝形压头在脆性材料表面的刻划或印压作用,在高效去除材料的同时将在工件近表面区域产生断裂、划痕、裂纹、位错、残余应力和污染等缺陷[1-2]。以Lawn,Evans和Mar-shall为代表的一批学者利用压痕实验从不同侧面、不同角度对脆性材料接触

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