研究論文
アルミニウム液滴の凝固後の形状に及ぼす圧力の影響
2002 年 74 巻 9 号 p. 563-570
詳細
2002 年 74 巻 9 号 p. 563-570
Die castings have various defects which depend on the initial solidification phenomenon. The metal drop method is useful for clarify the formation of these defects.
In this study, a melted aluminum droplet in a crucible was dropped onto a plane copper mold by pressure. The external shape and the shape of a vertical section of solidified specimens were examined. The maximum thickness of the specimens was measured. Also measured were area, periphery length, and shape factor of the bottom of the specimens quantitatively. Experiments using water drop were also performed.
The shape of the solidified specimen changed from TypeA, TypeB to TypeD as increasing maximum pressure (TypeA : disk-like or columnar, TypeB : doughnut-like at peripheral region and thin plate-like at center TypeD : complex at main part and simple at dispersed parts). A TypeB-D shape was also observed, which was neither the shape of TypeB nor that of TypeD. The solidification mechanism was proposed to obtain these shapes.
