2009 Volume 50 Issue 11 Pages 2604-2608
Gravity die casting of AC4C aluminum alloy with mechanical vibration (0–120 Hz) was conducted. Columnar rod specimens (φ25mm×L210mm) 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.