Computer Simulation and Experimental Validation of Low Pressure Sand Casting Process of Magnesium Alloy V6 Engine Block

Aluminum alloys have commonly used for engine blocks in the past ten years, and continues to rise in automotive industry. In order to future decrease the dioxide carbon emission and fuel consumption of cars, using magnesium alloys instead of aluminum alloys for fabricating engine blocks are very attractive for automotive industry. This paper reports the development of Mg alloy engine blocks produced by low pressure sand casting (LPSC) process with a new heat-resistant JDM1 alloy. For the purpose of predicating and eliminating the casting defects in Mg engine blocks, the LPSC process is modeled and simulated by computer. The effect of gating system geometries, iron chills, and the melt temperature on the shrinkage and porosity distribution of LPSCed Mg engine blocks are investigated, and then the optimum gating system design and LPSC parameters are obtain. Several engine blocks are practically cast with different LPSC parameters, and the result of dissecting the block casting validates the simulation accuracy very well. Finally, the Mg V6 engine block castings without defects go through GM leakage test standard and shows good mechanical properties on bulkhead, with yield strength(YS), ultimate tensile strength(UTS) and elongation of the magnesium engine block is nearly 150Mpa, 300Mpa and 10%, respectively.