由于我厂是小型工厂,缺少硅铁和原生铁,因此,炉料采用85％的回炉铁。用这种铁水浇注的铸件白口层厚,不能进行机械加工。我们针对这个问题,根据铝是促进石墨化的元素,同时又能促进形成铁素体组织,增加强度,在炉前加入少量的铝(加入铁水量的0.4％),解决了上述问题。 Because I plant is a small factory, the lack of ferrosilicon and primary iron, therefore, the charge used 85% of the iron back. Castings cast with this hot metal have a thick white layer and can not be machined. In response to this problem, we solved the above problems based on the fact that aluminum is an element that promotes graphitization and at the same time promotes the formation of ferrite and increases the strength by adding a small amount of aluminum (0.4% of the amount of molten iron) before the furnace.