航空学报 > 1999, Vol. 20 Issue (4): 39-43

镜面蒙皮拉形工艺参数研究

万敏1, 周贤宾1, 李晓星1, 伍惠2   

  1. 1. 北京航空航天大学机械工程及自动化学院;2. 成都飞机工业公司总工艺师室
  • 收稿日期:1998-07-03 修回日期:1998-08-25 出版日期:1999-08-25 发布日期:1999-08-25

PROCESS PARAMETERS IN STRETCH FORMING OF MIRROR SKINS

WAN Min1, ZHOU Xian bin1, LI Xiao xing1, WU Hui2   

  1. 1. School of Mechanical Engineering and Automation, Beijing University of Aeronautics and Astronautics, Beijing, 100083, China
  • Received:1998-07-03 Revised:1998-08-25 Online:1999-08-25 Published:1999-08-25

摘要: 滑移带是导致飞机镜面蒙皮报废的主要原因之一。通过分析镜面蒙皮拉形中变形程度、拉形速度、毛料几何尺寸、润滑与操作方式对滑移带的影响,确定了临界变形程度和拉形应变速率的合理范围。毛料几何尺寸的影响,反映在悬空段板料的宽长比值上,宽长比值增加,变形趋向于平面应变状态,易出现滑移带。良好的润滑方式有利于改善板料变形的均匀性,增加成形面内材料的变形程度。操作方式的选择,应充分考虑模具拉胀的作用,严格控制夹钳预拉量和补拉量,避免冲击和阶跃式的加载方式。

Abstract: Slip band is one of the main causes for faulty parts in stretch forming of airplane mirror skins. By means of analysis of the effects of deformation degree, stretching velocity, geometrical dimensions of the blank, lubrication methods and operation modes on slip band, the critical deformation degree and the reasonable scope of stretching strain rates are determined. The influence of geometrical dimensions of the blank on the slip band mainly depends on the width to length ratio of sheet materials in the hang region: the ratio increases, the deformation tends to plane strain state, and the slip band easily appears. Well lubrication methods are beneficial to improving the deformation uniformity of sheet materials and increasing the material deformation degree in the forming region. And the choice of operation modes ought to fully consider the function of die stretching, strictly control the jaws′ preliminary and supplemental tension values, and avoid the impact and stage loading modes.

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