不同偏离率下铝合金半球体壳体旋压模拟及应力、变形分析

Abstract

利用SuperForm/Marc软件模拟半球体壳体的旋压过程，研究了旋压过程中壳体壁厚位移的变化，并重点分析了影响旋压工件形状的一个重要因素即壁厚偏离率对工件应力分布及变形程度的影响规律。模拟结果显示：针对三种偏离率(0 (无偏离)、+5%、−8%)，旋压过程中壳体变形随着壁厚减薄率增加而增加，外层变形呈台阶状增加；同一变形时刻，变形大小顺序为：负偏离 > 零偏离 > 正偏离；不同的偏离率对壳体贴模情况影响很大，对应大尺寸半球壳体的旋压成形贴模性好坏顺序为：正偏离 > 零偏离 > 负偏离。 The process of aluminum alloy hemispherical shell spinning was simulated by use of the software of SuperForm/Marc. The change of the shell’s thickness was studied and the effect of the thickness deviation rate (an important factor for the influence law of deformation) and stress distribution in the spinning process was analyzed. For the three deviation rates (0 (no deviation), +5% and −8%), the simulation analysis showed that the deformation of shell increases as the thickness reduction ratio increases in the process of spinning, and the outer deformation of the shell increases with a shape of stair; in the meantime, the order of the shell’s deformation was: −8% > 0 > +5%. And the wall thickness showed a great difference under different deviation rates, and the order of the wall thickness precision of the shell in the spinning process was: +5% > 0 > −8%.