ISO 185:2005《灰铸铁》国际标准解读

Interpretation of the ISO 185:2005 GREY CAST IRON Standard

本文介绍了灰铸铁材料金相组织的基本构成要素,灰铸铁金相结构中的石墨形态和大小决定了灰铸铁的力学性能大小,而非基体组织。具有相同化学成分的灰铸铁件具有不同的力学性能,这和铸件的断面敏感性有关。灰铸铁的高强度是通过良好的孕育处理以改善石墨形态和大小获得的,而不是通过添加合金元素来实现。灰铸铁的热处理,并不是提高性能的最好方式,因为石墨形态决定了灰铸铁的性能,通过热处理使基体的任何变化带来性能的改进是有限的。

This paper introduced the basic composition of microstructure of grey cast iron. The tensile properties of the grey cast iron depend on the morphology and dimension of graphite rather than the matrix. The gray cast iron castings with the same chemical composition have different mechanical properties due to section sensitivity of the castings. The higher strength grades of grey cast iron are achieved with a well formed graphite form resulting from good inoculation, rather than by the introduction of unnecessary alloying elements. Heat treatment is generally applied to enhance material properties. Grey cast irons do not respond well to a heat treatment, because the graphite form principally dictates the properties and any change in the matrix resulting from a heat treatment operation provides little improvement.