浅析铸铁中硫的功能与控制

Analysis on Function and Control of Sulfur in Cast Iron

硫在铁液中主要以自由硫、化合硫和硫夹杂物的形式存在。本文分析了铸铁中硫的三种存在形式和它们之间的平衡关系,总结了自由硫的表面活性功能、硫化反应功能和抑制吸氮功能对铸铁组织性能的影响。结合生产实际,汇总了目前硫含量的测定方法和常用增硫脱硫措施,为铸铁中硫的合理控制提供了指导方向。

Sulfur mainly exists in the form of free sulfur, sulfur compounds and sulfur inclusions in liquid iron. In the paper, the three existing forms of sulfur and their equilibrium relationship in cast iron are analyzed. The influences of free sulfur’s surface activity, sulfuration and inhibition of nitrogen dissolution on structure and properties of cast iron are summarized. The determination methods of sulfur and measures of resulfurization together with desulfurization are introduced based on the production practice, which can provide a good guide for the reasonable control of sulfur in cast iron.