一、前 言 压铸铝合金时,瞬时以高速、高压由狭窄的浇口压入型腔内的液态金属,在型腔内引起紊流,致使铸件中卷入空气。分析压铸件中气体成份(表1),说明卷入的空气中含氮气较多。因此,压铸件不能进行象砂型及金属型铸件通常所进行的热处理和焊接工序。 表1 压铸零件中含气量的分析结果(％) 然而,近年来开发了PF法、真空压铸法、层流铸造法,使铝合金压铸件的热处理成为可能。而进一步要求高质量的普通压铸法在其铸件中的含气 First, the preface Die-casting aluminum alloy, the instantaneous high-speed, high pressure by the narrow gate into the liquid metal cavity, causing turbulence in the cavity, resulting in the casting into the air. Analysis of die-casting gas composition (Table 1), indicating that the air entrained in the nitrogen-containing more. As a result, die-castings can not be subjected to the heat treatment and welding procedures typically performed for sand and metal-type castings. However, in recent years, the PF method, the vacuum die-casting method, and the laminar casting method have been developed to make the heat treatment of aluminum alloy die-castings possible. Further demands for high quality common die casting method in its casting gas