加载路径对AA5083管件热态非金属颗粒介质成形性能的影响

将颗粒介质作为传力介质,应用于铝合金管件内高压热成形工艺。通过热单向拉伸试验建立AA5083板材的本构模型。通过管材热态颗粒介质胀形数值模拟,结合AA5083理论成形极限图的分析,研究了不同加载路径对管件壁厚分布、管端缩料量和主应变曲线的影响规律,并进行了相应的工艺试验验证。研究结果表明,合理匹配初始压头力和管端进给量参数,使预成形管坯在胀形区形成有益皱纹,可为胀形区管坯变形提供聚料作用,从而提高管件成形质量和胀形极限。

Formability of Hot Non-metallic Granule Medium of AA5083 Aluminum Alloy Tube under Various Loading Paths

Non-metallic granule (NMG) was used as the pressure-transfer medium and applied to the hot internal high-pressure forming technology on tube herein. The constitutive model of AA5083 sheet was created by the hot uniaxial tensile tests. Based on the numerical simulation of bulging on tube with NMG medium and the forming limit diagram (FLD), the influences of loading paths on the distribution of tube thickness, the contraction length of tube end and the path of principal strain were studied. All the work above were also verified by technological tests in the end. The results show that a reasonable match of initial punch force and axial feeding makes tube form a beneficial wrinkle in bulging region which is helpful in improving the forming limit because the material is gathered in the bulging region beforehand.