高速列车铝合金齿轮箱微观夹杂物研究

Study on Micro Inclusions in Aluminum Alloy Gearbox for High-speed Train

为提升高速列车齿轮箱的可靠性,采用金相及EDS能谱分析研究了高铁齿轮箱材料中的微观夹杂物的形态及成分。结果表明,微观夹杂物主要是富Fe相。通过MAGMAsoft软件模拟齿轮箱铸造过程发现,快速凝固时,形成的Fe相呈鱼骨状,凝固缓慢时,Fe相呈长针状。试样P-V曲线数据表明,裂纹更容易在长针状富铁相试样中扩展,说明危害性更大。设计齿轮箱铸造工艺时,关键区域应尽量采取激冷措施,降低铁元素的危害,提升齿轮箱的安全系数。

In order to improve the reliability of high-speed train gearbox,the morphology and composition of micro-inclusions in the material of high-speed train gearbox were studied by metallography and EDS analysis.The results show that the microcosmic inclusions are mainly Fe-rich phases.Magmasoft software is used to simulate the casting process of gearbox,and it is found that the Fe phase formed is fishbone shape when the solidification is rapid,while the Fe phase is long needle shape when the solidification is slow.The P-V curve data of the samples show that the crack is more likely to propagate in the long acicular iron-rich phase samples,indicating that the damage is greater.When designing the foundry process of the gearbox,drastic cooling measures should be taken in the key areas to reduce the harm of iron and improve the safety factor of the gearbox.