摘要
为了保证精铸件的成形精度,制造所用的模具型腔必须对铸件的收缩变形进行补偿。提出一种精铸过程位移场的数值模拟方法:通过涡轮叶片的精铸实验,测量与分析铸件上特定位置的温度值变化曲线,反向求解了界面换热系数随时间的变化关系,提高了铸件凝固过程中温度场数值计算的精度。通过设置适当的工艺参数和边界条件,基于熔模铸造温度场和应力场,对精铸过程进行耦合计算,得到了较为精确的凝固过程位移场,与实测结果吻合较好,为精铸涡轮叶片模具型腔的优化提供了量化参考依据。
In order to ensure the forming accuracy of castings,it is necessary to consider the compensation for the shrinkages in the mould cavity for turbine blades brought by the solidification process.In this article,a simple and efficient method is proposed for the numerical simulation of the displacement field for investment casting.Based on experiments of investment casting for turbine blades,with the identification of casting temperature data of specific positions,the interface heat transfer coefficient（IHTC） is established,and thus the simulation accuracy of the temperature field is improved cosiderably in the investment casting of turbine blades.Based on the proper process parameters and boundary conditions,real deformation of turbine blades is established by coupling the calculation of temperature field and the stress field.The calculation results are in good agreement with the experimental results.Therefore,the displacement field proves is effective for the optimization mould design for turbine blades.
出处
《航空学报》
EI
CAS
CSCD
北大核心
2009年第1期165-170,共6页
Acta Aeronautica et Astronautica Sinica
基金
国家"863"计划(2006AA04Z144)
国家科技支撑计划(2006BAF04B02)
关键词
数值模拟
熔模精铸
位移场
界面
换热系数
涡轮叶片
numerical simulation
investment casting
displacement field
interfaces
heat transfer coefficients
turbine blade
