皮下气孔是铸态球墨铸铁的常见缺陷,气孔形成的机理还没有被阐明,一般都假设它们的发生与硫化镁和水蒸汽间的化学反应有关。本文作者提出了新的假设:球墨铸铁形成皮下气孔是因为它有独特的凝固特点,而上述化学反应仅在某种程度上促使皮下气孔的形成。作者作了一些试验,在某种程度上证实了自己的假设。 Subcutaneous stomatal is a common defect of cast ductile iron, the mechanism of stomatal formation has not been elucidated, generally assume that their occurrence is related to the chemical reaction between magnesium sulfide and water vapor. The authors propose a new hypothesis that ductile iron forms subcutaneous pores because of its unique solidification characteristics, and the above chemical reaction only contributes to the formation of subcutaneous pores to some extent. The authors made some experiments, to some extent, confirmed their own assumptions.