New rheocasting technology of semi-solid AlSi7Mg alloy

The new technology for preparing semi-solid slurry of AlSi7Mg alloy and influence of specific pressure and injection speed on the rheodiecating process was investigated. The results show that the slurry prepared by low superheat pouring and weakly electromagnetic stirring for a short time is very homogeneous, and the rheodiecasting technological parameters are wider and helpful to obtain semi-solid castings of high quality. The thickness of the casting piece, the injection pressure and the injection speed have great influence on the filling ability. For 10 mm thick piece, the injection pressure should be equal to or more than 15 MPa, the injection speed should be equal to or more than 0.384 m/s; but for 5 mm thick piece, the injection pressure should be equal to or more than 20 MPa, the injection speed should be equal to or more than 1.152 m/s.