低温空気を用いた凍結鋳物生成における水分含有鋳造砂型の凍結・融解挙動

抄録

This paper reports the freezing and melting characteristics of a sand mold containing water on the freeze mold method. In the freeze mold method, water in the cast sand is frozen and the sand mold becomes hard without caking additives. In this study, the sand mold was cooled by cold airflow for using the freeze mold method in practical applications.
In the experiments, the sand containing water was filled into a rectangular container, and then cold air of -30°C was flowed into the container. After water in the sand was frozen, molten aluminum alloy of 900°C was cast into the sand mold to make a test piece. The freezing and melting behavior of water in the sand was investigated experimentally under the various water amount conditions.
As a result, it was found that water of 1 mass% in the sand was evaporated by the cold airflow in the freezing process. In the casting process, the movement of evaporation interface becomes slow as the water amount in the sand increases, on the other hand, the movement of melting interface is not influenced by the water amount so much.