The effects of low-speed process on the porosity

microstructure and mechanical properties of YZAlSi9 Cu3 die-casting parts were investigated by means of optical microscopy

X-ray inspection and mold flow analysis

etc

combined with orthogonal test and mechanical testing.The experimental results show that the air hole in the machining surface of an engine cylinder block is mainly caused by the unreasonable design of the low speed process.When the slow injection speed is more than 0.4 m/s

the entrapped-gas volume of the castings is increased

and the liquid of the piston is more than the piston oil

so comprehensive performance is decreased.When the slow injection low speed is 0.2 m/s

the casting structure presents sound with a little slag content and low porosing

so the mechanical properties are desirable.