2024铝合金挤压型材拉弯回弹分析

2024铝合金L截面挤压型材拉弯结构件是飞机壁板、地板及连接接头等部位的关键零部件,针对此类结构件拉弯成形回弹问题,基于位移控制的夹钳轨迹建模方法,建立了拉弯及回弹有限元模型,模拟分析了预拉量、补拉量及摩擦系数对回弹量的影响规律。结果表明:预拉量、补拉量及摩擦系数对回弹量有较大影响。随着预拉量、补拉量的增加,半径回弹率减小。挤压型材与模具之间使用有效的润滑剂,半径回弹率减小。采用正交试验方法模拟研究了预拉量、补拉量及摩擦系数对回弹量的影响程度。方差分析表明补拉量及摩擦系数在F_0.25(2,2)水平下对试验指标影响显著。

Springback Analysis of 2024 Aluminum Alloy Extrusion Profile in Stretch Bending

2024 aluminum alloy L-section extrusion profile stretch bending structure parts are key components in aircraft panel, floor and joint. Aiming at the stretch bending springback problem of this kind of structure part, a stretch bending and springback finite element model was established based on the displacement controlled clamp trajectory modeling method, and the influences of pre-stretching, post-stretching and friction coefficient on springback were analyzed. The significance of pre-stretching, post-stretching and friction coefficient to springback was studied by orthogonal experiment. The results show that increasing pre-stretching or post-stretching can reduce the radius springback ratio, the lubricant between extrusions with die reduces the radius springback ratio. The variance analysis of the orthogonal experiment shows that the post-stretching and friction coefficient have significant influence on the experimental indexes at the level of F0.25(2,2).