2A12铝合金带筋薄壁梯形环件挤压成形研究

Study on Extrusion Forming of 2A12 Aluminum Alloy Thin-walled Trapezoidal Ring with Ribs

为了克服2A12铝合金薄壁梯形环件不同壁厚及不同的内部形状立筋难以成形的问题,采用了预成形＋反挤压成形工艺方案。对不同凸模型腔最低高度和凸模圆角半径的薄壁梯形环件的成形进行了数值模拟和分析。利用统计软件进行了回归分析。结果为：当预成形凸模压下量为8.87 mm、凸模型腔最低高度为14.25 mm、凸模圆角半径为15.71 mm时,挤压过程中梯形环件立筋成形良好,各部分壁高协调生长,立筋底部缺陷消失,梯形环件的等效应变分布较为均匀。采用优化后的工艺参数和模具对模拟结果进行了验证,得到了符合尺寸精度要求的梯形环件。

In order to overcome difficult forming problem of the 2 A12 aluminum alloy thin wall trapezoid ring with different wall thickness and different internal shapes vertical ribs, the pre-forming ＋backward extrusion process was adopted.Forming of thin-walled trapezoidal ring with different minimum heights of punch cavity and corner radii of punch was numerically simulated and analyzed. Regression analysis was carried out by using statistical software. The results show that when the reduction of the pre-formed punch is 8.87 mm, the minimum height of the punch cavity is 14.25 mm, the radius of the punch is 15.71 mm, in the process of extrusion, vertical ribs of the trapezoid ring are well formed, the wall height of each part grows harmoniously, the defects at the bottom of the vertical ribs disappear, and the equivalent strain distribution of the trapezoidal ring is more uniform. The simulation results were verified by using the optimized process parameters and die. A trapezoid ring which meets the requirements of dimensional precision was obtained.