Experimental study on the filling process of the lost foam casting process of a cast iron plate

Lost foam casting owns a series of advantages, however, EPS pattern burns while the liquid metal fills, which makes the filling process complicated and directly leads to defects in castings. A measurement system of the liquid metal filling based on a modified contact time method (MCTM) was established. The filling of measured points is illustrated by a LED pattern, and the filling time of all the points is obtained by the analysis of the recorded movie. This method is free of limitation of signal acquisition channels. The system was applied into the experimental study of the filling of a vertical plate-shaped specimen of cast iron. The filling of one hundred positions was measured, and the filling profiles and filling velocity during filling process were obtained, which reflected the features of its filling process. The influence of some parameters including the metastatic head, the density of the EPS pattern, the thickness of coating and the permeability of sand mould on the filling process were investigated.