MODELING OF THERMAL STRESS DURING CASTING SOLIDIFICATION PROCESS

Numerical simulation of thermal stress during casting solidification process can predict crack, residual stress concentration, deformation. Though stress simulation involves too many complex problems such as numerical model, mechanical boundary condition and high thermo-mechanical parameters, it still retains as a difficult hotspot of macro-simulation of casting nowadays. Based on finite difference method (FDM), a 3D FDM/FDM numerical simulation system for temperature and stress analysis during casting solidification process was developed. To verify the system, a standard stress frame model and a practical casting were simulated. Pouring experiments have been carried out in the laboratory. The results of simulation coincided with those obtained from experiment and practical results. When adopting FDM to calculate casting thermal stress, thermal analysis and stress analysis can use the same FD model, which can avoid matching between different models and reduce the errors of temperature load transferring. It makes the simulation of fluid-flow, temperature and stress unify into one model.