Experimental research and optimization on hot extrusion shrinkage and thickening of 5A02 aluminium alloy thin-walled tube [5A02铝合金薄壁管材热挤压缩径增厚成形试验研究及优化]

作者：Qiu Z.-Y.; Xu X.-F.^*; Fu C.-L.; Xiao J.; Xiong G.-L.

来源：Journal of Plasticity Engineering, 2019, 26(5): 7-14.

DOI：10.3969/j.issn.1007-2012.2019.05.002

• 5A02 aluminum alloy
• Die cone angle
• Die shoulder
• Shrinkage and thickening
• Straight section of thickening area

To solve the problem of tapping threads directly at the end of a certain type of aircraft pull rod, the hot extrusion shrinkage and thickening forming method of 5A02 aluminium alloy thin-walled tube end was proposed for the first time, and the forming dies were designed and manufactured. The effects of the straight section size of thickening area, the length of the die shoulder and the die cone angle on the shrinkage and thickening behavior of thin-walled tube during hot extrusion were studied and the forming process path was optimized. The experimental results show that when the length and diameter of the straight section in the thickening area is too large,the straight section is liable to be instable to wrinkle. The material is easy to accumulate in the support area and the buckling phenomenon is easy to occur when the length of the die shoulder is too long. Under the condition that tubes can be preheated, the length of the die shoulder should be as shorter as possible. The tube located in the shrinkage area is easy to winkle and the radial thickening is not obvious in the thickening area when single pass hot extrusion forming with the die cone angle of 12°and 16° is used. After two passes hot extrusion forming with the large cone angle first and the small cone angle finally, the shrinkage section radial dimension of the forming part is increased from 1.00 to 4.06 mm, the thickening rate is 306% and the forming effect is good.

• 单位
  南昌航空大学