Numerical Modeling On The Temperature Field And Heat Stress Field In The Process Of Foundry Freezing

Promoting the development of traditional foundry industry by information technology is an important trend in development of foundry technology. Utilization of computer technology in the foundry production has been the mandatory condition of high quality manufacturing, and it is the development direction of foundry industry modernization.Finite element numerical method on temperature field and heat stress field, which are modeling the freezing process of foundry system is strongly promoting the development of foundry industry, and played an important roll on the following aspects:optimizing the design process; prevent disadvantage such as shrinkage void, shrinkage porosity aliquation, aliquation and hot cracking; decreasing residual stress and improving the cast quality.Firstly, it is generalized the development of numerical modelling on the freezing process and expected its trend in development. 3D elastoplastic FEM model in the transient temperature field and heat stress field are established and the mathematic model of initial condition, terminal condition and heat processing are also created. According to the character of heat stress and stress field during the foundry process, constitutive equation of heat elastoplastic model after the cast freezing is established, and full analysis are conducted on the parameter sampling, the parameters are terminal condition of cast/casting mould, high-temperature mechanical property of the material, and made a decision of using indirect model to calculate the heat stress.Analysis method on temperature field and heat stress field based on ANSYS is developed. Character of material properties varied according to the temperature is considered, nonlinear analysis is adopt. FEM analysis on the 3D temperature field and heat stress field of typical cast is conducted. According to the analysis result, on one hand, more reasonable distribution can be adopt to improve the pass percent of the casts, one the other hand, more suitable temperature, sand mould(material, dimension) and cooling position of casting can be selected to the target of cast processing optimization and servicing practical production.