熔模铸造条件下Ti6Al4V合金铸件与陶瓷型壳间界面换热系数研究

发布时间：2018-04-03 12:48

本文选题：钛合金　切入点：熔模铸造　出处：《金属学报》2015年08期

【摘要】：建立了Ti6Al4V合金铸件/铸型界面换热系数(h)的一维反算模型,从数学及数值模拟的角度研究了型壳热物性参数和热电偶定位等参数对h计算的影响,分析了不同参数影响的不同特点,据此对型壳热物性参数和热电偶定位位置等进行了修正,提高了h反算精度.修正计算参数后的反算结果表明,Ti6Al4V合金熔模铸造条件下,h的变化可分为4个阶段:(1)铸件为液态,h维持约440 W/(m2·K);(2)铸件表面生成完整凝固层,此阶段h下降近60%;(3)凝固层不断增厚至铸件凝固,此阶段h下降接近峰值的20%;(4)铸件凝固后,h随温度缓慢下降.在三维模型中对反算得到的h进行了验证,得到的模拟温度与实测温度基本吻合,表明反算得到的h较为准确,可以应用于Ti6Al4V合金熔模铸造过程的数值模拟中.
[Abstract]:The establishment of Ti6Al4V alloy casting / mold interfacial heat transfer coefficient (H) inverse model of one-dimensional mathematical and numerical simulation, from the angle of the effect of shell thermal parameters and thermocouple positioning parameters of H calculation, analyzes the different characteristics of different parameters, which modifies the thermal properties of shell parameters and position of thermocouple was increased by H, the inverse calculation accuracy. The parameters of calculation results show that the Ti6Al4V alloy casting condition, the change of H can be divided into 4 stages: (1) casting liquid, H maintained about 440 W/ (M2 - K); (2) the casting surface generates complete solidification layer, this stage h fell by nearly 60%; (3) the solidified layer thickened to continuous casting solidification, this stage h decreased close to the peak of 20%; (4) after solidification, the h temperature decreased slowly. In the three-dimensional model to verify the calculation to get the h, and the measured temperature based on the simulated temperature This agreement shows that the H obtained by inverse calculation is more accurate and can be applied to the numerical simulation of the casting process of Ti6Al4V alloy.

【作者单位】：清华大学材料学院先进成形制造教育部重点实验室;北京航空材料研究院;
【基金】：中欧航空科技合作项目欧盟第七框架项目国家重点基础研究发展计划项目2011CB706801 国家自然科学基金项目51171089和51374137 国家重大科技计划项目2012ZX04012011 国家高技术研究发展计划项目2007AA04Z141资助~~
【分类号】：TG249.5

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