(华南理工大学 国家金属材料近净成形工程技术研究中心，广州 510641)
摘 要: 通过测量挤压铸造过程的温度变化，采用基于非线性估算法的热传导有限元反算模型，求解不同挤压力下的界面传热系数(IHTC)。利用铸件中心模拟温度与测量温度验证模型的准确性；结合铸件表面和中心测温点温度变化讨论重力条件和挤压力条件下界面传热系数的变化规律，发现挤压力有效地增加了界面传热系数的峰值和稳定值。探讨挤压力对界面气隙的影响，对于ZL101A铝合金直接挤压铸造过程，50 MPa挤压力具有较好的挤压效果。
关键字: 铝合金；挤压铸造；界面传热；反算法；界面气隙
（National Engineering Research Centre of Near-net shape Forming for Metallic Materials,
South China University of Technology, Guangzhou 510641, China）
Abstract:The temperature histories throughout squeeze casting process under different applied pressures were recorded. The interfacial heat transfer coefficients (IHTCs) were calculated by using an inverse method based on the nonlinear estimation method. To validate the inverse method, the comparison between measurement and simulation temperatures in the center of castings was taken. IHTCs under gravity and pressure condition, respectively, were discussed with the surface and centre temperature histories of castings to obtain a general rule. The results show that the peak and stable values of IHTCs increase obviously with increasing the applied pressure. Additionally, the effect of applied pressure to interface air gap was discussed, and 50 MPa applied pressure performs sufficiently to direct squeeze casting process of ZL101A aluminum alloy.
Key words: aluminum alloy; squeeze casting; interfacial heat transfer; inverse method; interfacial air gap
