単ロール法と回転円盤アトマイズ法によるＺｎ‐２２Ａｌ急冷凝固材の特性比較

Abstract

Rapidly solidified Zn-22Al superplastic ribbon was produced by melt spinning process. The ribbon was pulverized and compacted in a closed-die, then subjected to forward extrusion under a condition at temperature of 250C. Tensile test of the extruded compact was carried out at 250C. Characteristics of the ribbon, the pulverized ribbon and the extruded compact were compared to those of rapidly solidified Zn-22Al superplastic powder and the extruded compact made by centrifugal atomization process already investigated.The ribbon had a fine and homogeneous microstructure similar to that of the powder by the centrifugal atomization. It was estimated that cooling rate of the rapidly solidified ribbon was almost equal to that of the powder, namely, 105C/s. Elongation of the extruded compact made by the pulverized ribbon was inferior to that made by the powder because of existence of pores in the compact.