【摘要】 对镁在球墨铸铁件中的分布状况及石墨球化的机理进行了研究。结果表明,镁在球墨铸铁件表面大量富集,在整个横截面上由外到内呈梯度分布。这是因为球墨铸铁液中的气泡在挤压力作用下双向迁移造成镁分布的不均匀,这种挤压力来源于由温度下降而引起的体积收缩及球墨铸铁中的石墨化膨胀。更多还原

【Abstract】 The distribution of magnesium in ductile iron and the mechanism of graphite modularization were studied.The experimental results show that the surface of ductile iron casting has a large amount of magnesium,and there is a gradient distribution of magnesium from outside to inside in the cross section.It can be explained that the heterogeneous distribution of magnesium is caused by the bilateral migration of the bubbles in the molten metal,the bubble migration is caused by the extrusion force which derives from the volume shrinkage of the liquid metal and the graphite expansion.更多还原