Effect of phosphorus on sulfide precipitation in strip cast low carbon steel

The effect of phosphorus addition on sulfide precipitation for strip casting low carbon steel containing copper was investigated and discussed with respect to the morphology, size and composition of sulfide. Both experimental results and mathematical calculation showed that the addition of phosphor-us retards the sulfide precipitation at high temperature, promotes the supersaturation of sulfur and makes more copper bearing and smaller sulfide at low temperature. Phosphorus also promotes sulfide precipitation in alpha-Fe instead of in gamma-Fe, so that with high cooling rate small and spherical copper sulfide forms instead of copper sulfide with a plate-like shape.