収縮及び強度測定によるアルミニウム合金の凝固温度範囲の区分

抄録

  A number of semi-solidus temperature of Al-Cu and Al-Si alloys were determined employing two experimental methods, namely by measuring the starting temperature of contraction and the critical temperature below which the cast material acquires strength. A slight difference was found between values of these two methods, the latter method having a tendency to show lower semi-solidus. It is thus suggested that the liquid-solid zone in phase diagram is divided into three zones by the following criteria. (1) Seme-liquid zone. (2) Primary semi-solid zone : range between semi-solidus determined by the contraction measurement and strength measurements. In this range, the material is characterized by low strength and high elongation. (3) Secondary semi-solid zone : range between semi-solidus determined by the strength measurement and solidus. In this range, the material shows medium strength and low elongation.