다이캐스팅 모바일 기기의 기공결함 감소를 위한 유동구조 설계

Abstract

Usually, the die-cast components used in small mobile devices require finishing processes, such as computernumerically controlled coating. In such cases, porosity is the most important defect. The shape of the moltenaluminum that passes through the runner and gate in a mold is the one of the factors that influences gasporosity. To define the spurt index, which numerically indicates the shape of molten aluminum after the gate,Reynolds number and Ohnesorge number are used. Before die fabrication, computer-aided engineering analysis isperformed to optimize the filling pattern. Finally, X-ray and surface inspection are performed after casting andmachining to evaluate how the spurt index affects porosity and other product parameters. Based on the resultsobtained herein, a new gating system design process is suggested.