Research on Cored Wire Re-Sulfurization Injection for Compacted Graphite Cast Iron

Abstract

To promote the application process of compacted graphite cast iron in non-automotive industry, cored wire re-sulfurization injection was developed for the production of compacted graphite cast iron. Firstly, ductile cast iron was produced by cored wire injection. Then, the effective final residual Mg level was reduced to the appropriate range for compacted graphite formation by feeding sulfidizing cored wire containing 99% S. In this paper, the influencing factors on percentage of compacted graphite were analysed, such as the final residual Mg level, cored wire injection speed. The results show that compacted graphite cast iron with less than 20% nodularity can be produced steadily on the condition of adopting the correct speed and the added sulfidizing cored wire in the range from 0.8m/t to 0.9m/t. Practice has proven that cored wire re-sulfurization injection would be most appropriate for jobbing foundries intending to manufacture compacted graphite cast iron castings for engineering industries.