项目名称: 熔石英元件亚表面加工缺陷形成机理与控制技术研究
项目编号: No.U1230110
项目类型: 联合基金项目
立项/批准年度: 2013
项目学科: 物理学II
项目作者: 王洪祥
作者单位: 哈尔滨工业大学
项目金额: 54万元
中文摘要: 基于宏观压痕断裂力学理论、微观分子化学键断裂机制对加工过程中各类裂纹成核机制进行定量分析,研究熔石英材料亚表面加工缺陷形成机理。确定熔石英加工表面、亚表面质量表征参数,提出一种无损、快速的亚表面损伤检测和表征新方法,实现亚表面损伤的无损检测和表征,建立熔石英加工表面及亚表面缺陷综合评价体系。基于光滑质点流体动力学有限元分析方法模拟磨粒与工件之间相互作用过程,分析亚表面划痕和微裂纹的形成、扩展过程及其影响因素,寻找抑制和减小亚表面裂纹扩展有效方法。建立脆塑转变临界切削深度预测模型,确定产生裂纹的临界载荷,分析各种工艺参数对脆性材料裂纹形成和扩展的影响规律。建立加工表面粗糙度、亚表面裂纹深度与加工工艺参数之间关系预测模型,实现亚表面损伤的准确预报。分析加工工艺参数与材料特性对加工表面、亚表面质量的影响规律,通过合理选择工艺参数和优化加工工艺流程达到有效控制加工表面质量的目的。
中文关键词: 亚表面裂纹;亚表面损伤;表面粗糙度;超精密加工;有限元分析
英文摘要: The quantitative analysis is done for various types of cracks formation mechanics owing to machining process based on macro-indentation fracture mechanics theory and the microscopic chemical bond-breaking mechanism, the mechanism that generate subsurface damage is studied for fused quartz material. The assessing parameters of machined surface quality is defined, a novel detection and assessing method is proposed for the machined surface and subsurface defects of fused quartz material, which can detect subsurface damage rapidly and is non-destructive to optical component. The interaction process between the abrasive and tworkpiece is simulated based on smooth particle hydrodynamics finite element method. Otherwise, the formation, propagation and its influencing factors of subsurface micro-crack and scratch marks are analyzed, and the effective means of suppressing and reducing the propagation of subsurface cracks is proposed. The prediction model of the critical cutting depth of brittle-ductile transition which may generate cracks is established, and the critical load is defined, also the effects of various process parameters on the formation and extension of cracks in brittle materials are analyzed. In order to achieve a correct forecast on subsurface crack depth, the prediction models on the relationship betwee
英文关键词: subsurface crack;subsurface damage;surface roughness;ultraprecision machining;finite element analysis