【摘要】 研究了多点拉形过程中3种加载路径对板料拉形质量的影响。基于平面应变假设,对多点拉形和等差曲率冲头主动加载拉形中铝合金薄板的受力特点进行了对比分析,同时应用数值模拟研究了多点拉形与多点冲头主动加载拉形中3种路径对板料应力、应变及延伸率分布的影响规律。结果表明:与多点拉形相比,等速冲头主动加载、等时冲头主动加载及等差曲率冲头主动加载3种拉形方式均能减小板料钳口处的应力集中,提高工件的应力、应变、延伸率分布均匀性,其中等差曲率冲头主动加载路径拉形效果最好。更多还原

【Abstract】 In This paper the influences of three different loading paths on the quality of stretch-forming were studied.Based on the plane strain assumption,the s tress state of Al alloy sheet between multipoint stretch-forming and equidifferent-curvature punch active loading stretch-forming were compared and analyzed.The strain,stress,elongation distribution of the multi-point stretch-forming and the multi-point punch active loading stretch-forming under three different loading conditions were studied by numerical simulation.Results show that,compared with the multi-point stretch-forming,constant velocity punch active loading,isochronous punch active loading and equidifferent-curvature punch active loading can not only reduce the stress concentration in the position between the sheet and jaw,but also improve the uniformity of the distribution of stress,strain and elongation.The results confirm that equidifferent-curvature punch active loading method can achieve the best formability of Al alloy sheet.更多还原