长流程高压压铸工艺参数优化与应用研究OA

The influence mechanism of process parameters of long flow high pressure die casting(HPDC)on the quality of Al-Si-Mg alloy castings is studied systematically by the method of finite element analysis and orthogonal test.Taking a long process general cavity model as the research object,the comprehensive effects of four parameters of pouring temperature,mould preheating temperature,filling rate and injection speed on shrinkage cavity volume,filling time and solidification time of castings are studied.The flow and solidification behavior of molten metal is analyzed by numerical simulation.Combined with orthogonal test design,the multi-objective optimization index is weighed by comprehensive balance method.The optimal process parameters determined by optimization are 720℃pouring temperature,180℃mould preheating temperature,45％filling rate and 5.5 m/s injection speed.Under this parameter combination,the shrinkage volume of the casting is reduced to 2.606 cm3,72.7％less than the initial process;the filling time is reduced to 0.763 s and the setting time is reduced by 5％.The numerical simulation and experimental verification show that after optimization,the defects of castings are significantly reduced,the filling sequence and solidification sequence tend to be reasonable,and the improvement effect is obvious especially for the hot joint area easy to produce shrinkage cavity in the long flow structure.The quantitative relationship between process parameters and casting quality is revealed,which provides theoretical basis and engineering practice guidance for process optimization of complex thin-wall aluminum alloy die castings.