Effects of mechanical vibration on cooling rate and DAS of AC4C aluminum alloy gravity die castings

Abstract

Gravity die casting of AC4C aluminum alloy with mechanical vibration (0-120Hz) was conducted. Columnar rod specimens (φ25 mm × L210 mm) were cast to investigate the effect of mechanical vibration on the cooling rate and the dendrite arm spacing of AC4C aluminum alloy castings. The cooling rate increased by imposition of the mechanical vibration, and increased with the increase of the vibration frequency. When the mechanical vibration imposed, the mold temperature increased quickly and reached higher temperature compared with no vibration condition. The dendrite arm spacing in outer region of the specimen decreased by mechanical vibration, and decreased with the increase of the vibration frequency. In the case without mechanical vibration, the specimen showed smooth surface. But the surface of specimen became rough by the imposition of the mechanical vibration. © 2009 The Japan Institute of Metals.