Abstract：A new method is proposed to evaluate the process parameters by the solid-liquid interface position, thermal gradient angle and the axial thermal gradient. The effects of the process parameters on the solid-liquid interface position, thermal gradient angle and the axial thermal gradient were simulated by ProCAST using LMC(Liquid Metal Cooling) and HRS(High Rate Solidification) processes. The results show that HRS process is little affected by the mold thickness, the dominant heat transfer factor in HRS is radiation from the mold surface, and the dominant heat transfer factor in LMC either mold thermal conductivity or mold-metal interface heat transfer; increasing furnace temperature is beneficial to increase the axial thermal gradient; the withdrawal rate is the most important process parameter which significantly affects the thermal field during solidification, as the withdrawal rate increases, the axial thermal gradient first increases and then decreases, therefore, it is necessary to apply different withdrawal rates for different alloys. After holding 10min at different pouring temperatures, a uniform temperature is achieved, and it has slight influence on the subsequent solidification. It has been put forward that the solid-liquid interface position, thermal gradient angle and the axial thermal gradient can be utilized as a serial of efficient analysis standards for optimization of process conditions independent of casting geometry.
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2016, Vol. 44 
