压铸高强韧铝合金汽车底盘结构件的组织与力学性能

Microstructure and Mechanical Properties of Die Casting Automobile Chassis Structure Parts

针对某汽车铝合金结构件的压铸成形,应用数值模拟,以了解铝液流动充型状态与铸件缺陷的分布,优化了铸件的浇注系统与排气系统。在自主研发的高真空压铸技术基础上,研究了金属液充型时模具型腔真空度对铸件组织和性能的影响。结果表明,高真空压铸可以显著降低铸件的含气量,提高铸件致密度;与普通真空压铸相比,高真空压铸件的抗拉强度、屈服强度、伸长率、硬度分别提高了21%、29%、18%、10%。

Filling and solidification as well as defect distribution of a aluminum alloy die casting structure parts were analyzed by the numerical simulation.The gating-exhausting system for the structure parts was optimized.Based on the self-developed high vacuum die casting technology,effects of vacuum degree in filling process on microstructure and mechanical properties of the structure parts were investigated.The results reveal that high pressure die casting can reduce greatly the gas content in the structure and improve the relative density of the parts.Compared with those of the conventional vacuum die casting,tensile strength,yield strength,elongation and hardness of the structure parts are increased by21%,29%,18%,10%,respectively.