大规格镁合金环形件新型挤压成形工艺及模具设计

针对传统工艺难以制备大规格镁合金薄壁环形件的情况,提出了一种曲母线通道连续翻转挤压成形新工艺.根据成形过程中的金属流动特性,为了避免坯料出现翘曲情况,制定了多次翻转成形工艺方案;采用主应力法对新型工艺进行力学解析;采用Deform有限元软件开展数值模拟,对成形力公式进行验证;通过正交实验,并基于变形均匀性评价因子,对成...

New extrusion process and mold design for large-scale magnesium alloy ring parts

For the difficult in producing large-scale magnesium alloy thin-walled ring parts by traditional process,a new process of continuous flip extrusion for curved busbar channel was proposed. According to metal flow characteristics in forming process,the process scheme of multiple overturning forming was established to avoid the warping of billet,the mechanical analysis of the new process was conducted by principal stress method,and the forming process was numerically simulated by finite element software Deform. Furthermore,the forming force formula was verified,and the forming process and mold structure parameters were optimized by orthogonal experiment and based on the evaluation factor of deformation uniformity. The results show that considering the structural dimension of formed parts and the single deformation amount allowed by the new process,the billet needs to be flipped and extruded four times,and the expanding force formula and the maximum pressure formula with taper angle α of inner concave die as independent variable are derived. In addition,compared with the simulation results of FE Deform with α = 20°,23° and 25°,the error is less than 10%. Finally,the extrusion process parameters are the extrusion speed of 1 mm·s^-1 and the taper angle of inner concave die of 23°,and the die of the new extrusion process is designed to give a new way to realize the short process and low cost manufacturing of large-scale magnesium alloy thin-walled ring parts.