Abstract
Both the casting shrinkage and the total thermal expansion in a solid state (from room temperature to melting or solidus temperature) of ZAC#1, Silmin (13%Si), AZ91 and pure Zn were measured when there was nothing to prevent the thermal shrink of casting such as insert cores. The relationship between the casting shrinkage and the total thermal expansion was also discussed. The main results are as follows. (1) The casting shrinkage of metals takes a value close to the total thermal expansion of metals in a solid state, but the relationship between them is very complicated. (2) Both the solidification manner of castings and the temperature distribution in castings during solidification are very important functions for the relationship between them. For the solidification of casting in a pasty manner, the casting shrinkage becomes larger than for the solidification of casting by the skin formation, and the casting shrinkage becomes smaller as the temperature gradient in castings increases.
