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基于反热传导法,建立了铸件/铸型界面传热系数反求数学模型.将铸铁件实际冷却曲线作为输入条件,成功获取了消失模铸件/铸型界面传热系数,同时建立了消失模铸件/铸型界面传热系数随时间变化的数学模型.当铸型温度为20℃时,传热系数服从h(t)=182.8-182.1×(7.23×10-5)t;当铸型温度为50℃时,传热系数服从h(t)=181.7-237.1×(1.45×10 4)t.采用反求获取的铸件/铸型界面传热系数对铸件凝固过程的温度场进行模拟.结果表明,与采用经验常数界面传热系数相比,采用反求法获取的界面传热系数的温度场模拟更接近实际.“,”A method based on the inverse heat transfer to obtain the interfacial heat transfer coefficient was established.Take the cooling curve of the iron castings as input data,it can obtain the heat transfer coefficient between the iron castings and mold in lost foam casting.When the temperature of the mold is 20 ℃,the coefficient is followed as the equationh(t) =182.8-182.1 × (7.23 × 10-5)t,while the temperature is 50 ℃,the coefficient is followed as h(t) =181.7-237.1 × (1.45 × 10-4)t.The temperature field was simulated based on the coefficient obtained by the method.The results reveal that compared with that of ones with empirical constant,the simulated results are well agreement with the practical temperature field.