新能源汽车4032铝合金轴承座闭塞式背压成形工艺数值模拟和实验研究

目的新能源汽车空调压缩机轴承座有着薄壁、多阶梯、外形复杂的特点,极易在成形过程中产生充填不满、折叠和拉裂等质量问题,为提高其成形质量,对其成形工艺进行仿真和优化。方法对"T"形和"帽"形两种预锻坯料采用闭塞式背压成形工艺的成形情况进行模拟,依据所得结果对相关工艺参数和配套模具进行相应的优化。结果在有背压力的情况下,"T"形预锻坯料的最大成形载荷由无背压时的927t降低至78.2t,并且载荷上升稳定,各成形阶段过渡平滑,易于调控。"帽"形坯料在成形过程中金属的流动更加充分,模具型腔充填得更加饱满,无"T"形坯料成形过程中的充不满等情况。材料的Si颗粒偏聚也得到了改善,晶粒得到细化。结论背压力的存在和预锻坯料形状的调控,使最终的成形载荷、成形质量以及零件的微观组织有了极大的改善。

Numerical Simulation and Experimental Investigation on Enclosed Die Forging with Back Pressure for 4032 Aluminum Alloy Bearing Pedestal of New Energy Vehicle

The work aims to simulate and optimize the forging technology so as to improve the forging quality aiming at the problems of that A/C compressor bearing pedestal of new energy vehicle has the characteristics of thin wall, multi steps and complex shape and forging defects such as filling dissatisfaction, folding and cracking are easy to occur in the forging. The forging situation of "T" shaped and "cap" shaped pre-forging blanks by enclosed die forging with back pressure was simulated, and the related process parameters and matching dies were optimized according to the obtained results. Under the condition of back pressure, the maximum forging load of T shaped pre-forging blank was reduced from 927 t without back pressure to 78.2 t, and the load rose steadily, and the transition of each forging stage was smooth and easy to control. The metal flow of "cap" shaped blank was more sufficient in the forging process, the die cavity was fully filled, and there was no insufficient filling in the forging process of "T" shaped blank. The segregation of Si particles of the material was also improved and the grains were refined. The existence of back pressure and the regulation of pre-forging shape have greatly improved the final forging load, forging quality and microstructure of parts.