基于刚度与应力演变机制的航空整体结构件加工变形预测理论建模  

Mathematical Modeling of Aeronautical Monolithic Component Machining Distortion Based on Stiffness and Residual Stress Evolvement

作　　者：黄晓明[1,2,3] 孙杰[1,2] 李剑峰[1,2] 

机构地区：[1]山东大学机械工程学院,济南250061 [2]山东大学高效洁净机械制造教育部重点实验室,济南250061 [3]滨州学院机电工程系,滨州256600

出　　处：《机械工程学报》2017年第9期201-208,共8页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(51275277)

摘　　要：航空整体结构件在铣削过程中,由于材料去除产生的毛坯初始应力重分布和结构刚度演变导致工件发生加工变形。针对这一问题,借助于生死单元技术建立隔框件加工变形预测有限元模型,获得材料去除过程工件变形规律。基于等效弯曲应变能方法,计算加工过程工件刚度变化规律;通过毛坯初始的应力和去除材料产生的弯曲附加应力的叠加分析,结合应力-工件刚度演变特点,借助于材料去除产生的附加力矩分析,构建航空隔框件加工变形数学模型,对隔框工件加工过程变形进行预测分析。将有限元计算结果与数学解析模型计算结果对比,研究表明两种方法获得的加工变形规律相吻合,工件变形特征与去除材料的初始应力状态变化规律相一致。Aeronautical monolithic component would be distortion in the process of milling due to the initial residual stress redistribution and structural stiffness evolution for the material removal. In this research, finite element modeling of machining distortion is established by the life and death technology, and the deformation law is got for material removal. The structural stiffness of aeronautical monolithic component is calculated based on the equivalent bending strain energy method. Combining with the characteristics of residual stress and stiffness evolution, machining additional torque model of material removal is established. The machining distortion of the frame workpiece is forecasted by the machining deformation mathematical model. The result obtain from FEM model agrees well with that from mathematical model, and the results show that deformation characteristics and the initial stress state of the removing material are consistent.

关 键 词：等效弯曲应变能 刚度演变 残余应力 加工变形 数学建模 

分 类 号：TP311[自动化与计算机技术—计算机软件与理论]