2004 Volume 76 Issue 3 Pages 185-191
Aiming at manufacturing excellent iron castings which possess better toughness, wear resistance, solid lubricity, etc., than traditional iron castings, the semi-solid casting process has been studied extensively by using various methods. However few trials have been carried out on semi-solid casting systematically to develop a practical process. In the present study, fundamental estimation of the semi-solid casting process was done for the purpose of making about 50 kg iron castings, using mechanical rotation and cooling plate as a solid particles distributing/fining method. The mold filling ability of semi-solid slurry was investigated as well as the microstructure and mechanical properties of the cast material.
Experimental results of mold filling using stepwise shaped mold confirmed that semi-solid iron fills smoothly into cavity with a thickness of 10 mm. It was also observed that 3 mm thickness cavity is filled completely when solid fraction is less than 0.05. The microstructure and mechanical properties of semi-solid iron casting are better than usual castings. Furthermore, simulation of flow and heat transfer was also attempted to predict the cooling process of metal slurry on the cooling plate. It was possible to quantitatively estimate the effects of the cooling plate.