基于自由弯曲技术的6061铝合金管的弯曲成形性能研究  

Study on Bending Formability of 6061 Aluminum Alloy Tube Based on Free Bending Technology

作　　者：魏文斌 程旋 余耀晖 王成 熊昊 王辉[3,2] WEI Wen-bin;CHENG Xuan;YU Yao-hui;WANG Cheng;XTONG Hao;WANG Hui(College of Material Science and Technology;College of Mechanical and Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China;Jiangsu Key Laboratory of Nuclear Energy Equipment Materials Engineering,Nanjing 210016,China)

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016 [2]江苏省核能装备材料工程实验室,南京210016 [3]南京航空航天大学机电学院,南京210016

出　　处：《精密成形工程》2018年第4期28-34,共7页Journal of Netshape Forming Engineering

基　　金：中央高校基本科研业务费专项资金(NS2016052)

摘　　要：目的对6061铝合金管开展三维自由弯曲成形的研究。方法对不同弯曲半径的铝合金管进行了弯曲模拟成形,并根据模拟结果对铝合金管进行实际成形研究。结果根据对6061铝合金管进行的弯曲半径为60,70,80 mm的有限元模拟成形结果,发现管材壁厚中性层向弯曲外侧发生明显偏移,且弯曲半径越小,向弯曲外侧的偏移量越大;管材内侧管壁增厚,最大增厚为17.2%,管材外侧壁厚减薄,最大减薄不超过4%,发现随着弯曲半径的减小,管材内侧增厚愈发明显,而减薄变化较小,同时对管材截面畸变进行分析,发现最大椭圆度不超过8%;通过对比模拟结果、实验结果与设计模型,发现管材模拟的弯曲半径最大偏差不超过8%,实验结果则不超过6.5%,而管材模拟的弯曲角度最大偏差不超过4.5%,实验结果则不超过3%,同时发现当弯曲较小时,内侧发生明显起皱,而弯曲外侧也有轻微壁厚减薄导致的畸变缺陷,这与模拟结果吻合。结论管材壁厚中性层向弯曲外侧偏移与自由弯曲系统轴向推力P_L有关,轴向推力使得管材的受压区域增加,而受拉区域减小,导致壁厚中性层外移;实验结果与模拟结果相吻合,验证了模拟对实验成形指导的可靠性。This paper aims to study the three-dimensional free bending of 6061 aluminum alloy tube. The aluminum alloy tubes with different bending radii were simulated, and the actual forming of aluminum alloy tubes was studied based on the simulation results. According to the finite element simulation forming of the 6061 aluminum alloy tube with bending radii of 60 mm, 70 mm and 80 mm, it was found that the neutral thickness of the tube wall was significantly shifted toward the outside of the curve, and the smaller the bending radius, the greater the deflection to the outside of the curve. Others, the inner wall thickness of the tube was thickening, the maximum thickening was 17.2%. The thickness of the outer wall of the tube was thinned, and the maximum thinning did not exceed 4%. It was found that as the bending radius decreased, the thickening of the inside of the tube became more pronounced and the change in thinning was small. At the same time, the distortion of the tube section was analyzed and the maximum ellipticity was not more than 8%. By comparing the simulation results, experimental result and design model, it was found that the maximum deflection of the bending radius of the tube simulation did not exceed 8%. The experimental result was not more than 6.5%, but the maximum deflection of the tube simulation bending angle did not exceed 4.5%, the experimental result did not exceed 3%, and it was found that when the bending was small, the inner side was obviously wrinkled, and the distortion defect caused by slight ground thickness thinning was also found on the lateral side of the bend, which was consistent with the simulation results. The deviation of the neutral thickness of the tube wall to the outside of the bending is related to the axial thrust P_L of the free bending system. The thrust of the tube increases the pressure area of the tube, while the tension area decreases, resulting in the shift of the thickness of the neutral layer. The experiment result is in consistence with the simulation result. The re

关 键 词：6061铝合金管 自由弯曲 有限元模拟 实验成形 

分 类 号：TG306[金属学及工艺—金属压力加工]