ダイカスト製品に発生した内圧を有するガス欠陥に対する鋳巣低減圧縮処理

抄録

  In the high pressure die casting products, it is difficult to prevent the formation of gas porosities, which adversely affect the mechanical properties or air-leakage resistances of such products. In this work, the products after casting were subjected to compression tests to reduce gas porosities having an inner pressure. From the experiments of compressing the products, the porosities were reduced efficiently by applying a 10% compressive strain. These porosities were quantitatively confirmed to be gas porosities by the analysis of the fractal dimensions of the shape of the porosities. From the finite element analysis of the model containing a circular defect with an inner pressure under compression, the porosities were reduced efficiently by applying a 10% compressive strain. From the results of both experiments and finite element analysis, it is concluded that compression processing is an effective method of reducing gas porosities and improving the mechanical properties and air-leakage resistances of die casting products.