铝合金薄壁框架件加工变形的应力分布研究

7075航空铝合金薄壁框架件加工变形的预测是构件形变控制领域的技术难题,掌握铝合金薄壁框架件上的加工应力分布对预测构件变形有着重要的作用.本文运用弹性力学理论,在实验基础上,利用层削法和X射线衍射应力测试技术,建立了薄壁框架件的应力与弯曲变形的力学模型.模型反映了加工应力和初始应力对构件实际变形的影响机制,在此基础上,再通过数学解析方法,以这两种应力场分布为主变量,构建了薄壁框架构件应力与变形的函数,完成了对构件最大变形挠度的计算.通过比较实验所测构件变形值与计算得到的变形结果发现:构件实际测量最大变形量基本处于数学解析函数计算变形区间内,数据偏差在20~50μm.研究结果表明:在已知初始应力、结构尺寸、加工参数条件下,解析函数能有效地预测出薄壁框架件加工后的变形,可为薄壁构件加工变形控制提供工艺指导.

Study on stress distribution resulted in processing deformation for Al-alloy thin-wall component

The prediction of the deformation of 7075 Al-alloy thin wall component is a difficult problem to be solved in the control of deformation, it is important to understand the distribution of stress distribution on the thin wall component of aluminum alloy. In this paper, the mechanical model of stress and bending deformation of thin-walled component is established by using the theory of elastic mechanics and the layer cutting method and the X-ray diffraction stress testing technique. The model explains the influence mechanism to the actual processing component deformation force and initial stress, which constructed the thin-walled component member stress and deformation functions and completed the calculation of the maximum deflection of the component with two kinds of stress distribution as main variables through mathematical analysis method. The results show that the actual measurement of the maximum deformation of the component is in agreement with the analytical function calculation of the deformation range, the data deviation in the 20~50 μm. The results show that the analytic function can predict the deformation of thin-walled component members after processing under the condition of known initial stress, structure size and processing parameters, and can provide guidance for controlling the processing scheme of thin-walled components.