工艺参数对触变模锻复合材料影响的仿真研究

Simulation study on the influence of technical parameters on thixo-forging composite material

采用商业有限元软件Deform-3D对触变模锻Al-7%Si合金/Al-17%Si合金复合材料进行仿真模拟,研究了坯料初始温度、模具温度对复合成形的影响规律。模拟结果表明:下坯料初始温度较低,复合界面线严重偏靠锻件中部上表面,底部充型不完全;下坯料初始温度较高,界面处坯料温度和应力不均匀程度严重。随着模具温度下降,坯料温度降低快、应力增加快,半固态成形时间不充分,复合界面处坯料温度、应力不均匀性加重,复合制件下部出现未充满现象。上坯料初始温度为580℃、下坯料初始温度为570℃、模具温度为400℃时,触变模锻复合充分,充型饱满,界面处温度、应力分布较为均匀,界面线直线居中,复合制件中部薄。并通过实验验证了模拟的可靠性。

The forming process of thixo-forging alloy Al-7% Si / Al-17% Si was simulated by finite element software Deform-3D. The influences of billets initial temperature and die temperature on composite forming were investigated. Simulation results show that when the initial temperature of the bottom billet is low,the composite interface line is close to the upper surface of middle part,and the bottom is not filled entirely; however,when the initial temperature of the bottom billet is high,the billet temperature and stress at interface were seriously uneven. With the die temperature of die drops,the billets temperature drops fast and the stress increases fast,so the semi-solid forming time becomes inadequate. With the bad inhomogeneity of billet temperature and stress at interface,the lower part of the composite part is filled incompletely. When the initial temperature of top billet is 580 ℃,the initial temperature of bottom billet is 570 ℃,and the die temperature of die is 400 ℃,the thixo-forging is composited entirely and filled fully with constant and even billet temperature and stress at interface,straight interface line in the middle,thin central part of the composite part. The reliability of the simulation was verified by experiments.