A new technology,semi-solid casting(thixocasting) method,was used to replace the conventional hot forging process to form AISI420 stainless steel air-turbine blade.The power law cut-off(PLCO) material model in Procast software was used to simulate the thixocasting process.The thixocasting process was simulated.The results show that the reasonable technology parameters for air-turbine blade thixocasting process are obtained:billet temperature 1 483-1 485 °C,piston velocity 12-15 m/s and die temperature is about 400 °C.
There exist many problems in producing four-way valve of HPb59-1 alloy for an air-conditioner by traditional solid state hot forging,i.e.larger forming loads,lower material utilization,larger subsequent machining allowance and nonuniform microstructure.For this reason,based on the orthogonal test,the semisolid diecasting process of a certain type of four-way valve was simulated with FLOW-3D.The simulation results show that the optimized process parameters are:the pouring temperature of 897.25 ?C,the shot velocity of 2.0 m/s and the preheated die temperature of 260 C.The simulation results demonstrate that the cavity can be filled smoothly and completely,the surface defects are small,the temperature field and the pressure field are uniform,and the casting quality is satisfactory.The effectiveness and availability of applying this technology are well verified by the numerical simulation.
