硬脆材料旋转超声加工高频振动效应及刀具磨损智能监测系统研究

项目名称： 硬脆材料旋转超声加工高频振动效应及刀具磨损智能监测系统研究

项目编号： No.51475106

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 机械、仪表工业

项目作者： 王洪祥

作者单位： 哈尔滨工业大学

项目金额： 80万元

中文摘要： 硬脆材料微结构件的尺寸小、承载能力低，在旋转超声加工时易发生边角破裂和脆性断裂，刀具磨粒容易脱落，加工质量难以保证。本课题以BK7玻璃材料微结构件为研究对象，用自定义的无量纲特征参数表征高频振动效应的强弱，实现对硬脆材料旋转超声加工中高频振动效应的定量表征，提出适用于旋转超声加工的表面形成过程新模型。分析初始裂纹成核的原因以及材料粉末化的形成机理，研究材料的惯性效应引起的粉末化层向切屑层/裂纹层的演化机制，确定旋转超声加工过程中脆性材料的脆-塑转变临界条件。综合考虑弹性应力场和塑性应力场对裂纹扩展深度的影响，建立工件表面粗糙度与亚表层裂纹扩展深度之间的非线性关系模型，实现对亚表层损伤深度的有效预测。利用经验模式分解法、广义隐Markov模型建立不同信号特征与刀具磨损状态之间关系模型，开发出基于多物理域信息融合的刀具磨损智能监测系统。本项研究工作对提高军工产品质量和成品率具有极其重要的意义。

中文关键词： 旋转超声加工；高频振动；亚表面损伤；精密磨削；刀具磨损

英文摘要： Due to its the small size, low bearing capacity, the hard-brittle micro-structure component could repture and fracture easily in the rotary ultrasonic machining process. In addition, the abrasives on the tool tended to detach, which brought it difficult to guarantee the machining quality. BK7 glass micro-structures are investigated in this topic, and a novel dimensionless parameter is defined to characterize the effects of the ultrasonic vibration to realize the quantitative characterization of the high-frequency vibration effects in the rotary ultrasonic machining process of hard-brittle material. Based on these investigations, a new surface formation process model adopted to the RUM prosess is proposed. The nucleation mechanisms of incipient cracks and the formation mechanisms of material pulverization are analysized, also the evolutionary mechanisms of the pulverization layer to the chipping/cracking layer is investigated, and the brittle-ductile transition critical condition is determined. By considering the combined effects of the elastic and plastic stress fields on the cracks, a nonlinear model between the surface roughness and the subsurface damage depth is proposed in order to realize the effective prediction of subsurface damage depth. The relationships between signal characteristics in multi-physics domain and tool wear are established using the empirical mode decomposition method and generalized hidden Markov model，and a novel intelligent monitoring system of tool wear based on multi-physics domain information fusion is developed in the end. This research has a great significance to improve the quality and yields of military products.

英文关键词： rotary ultrasonic machining;high frequency vibration;subsurface damage;precision grinding;tool wear