Effect of alloying elements on graphite and cementite eutectic temperature of cast iron

摘要

The effects of alloying elements on graphite (T{sub}EG) and cementite eutectic temperature (T{sub}EC) of cast iron, and the difference between them (ΔT{sub}E) were investigated. A thermal analysis system consisting of three cups was used tomeasure eutectic temperature. The order of the expanding effect on ΔT{sub}E is as follows: Si> Al> C{sub}(<2.9%)> Cu> Co> P> Ni> C{sub}(>2.9%). The order of the narrowing effect on ΔT{sub}E is as follows: B> S{sub}(>0.44%)> V> Cr> S{sub}(<0.44%)> Mn>Nb> Ti> Sn> W> Mo> Sb. Mn and Ti form sulfide, so that they expand ATE for a low content of element and narrow ΔT{sub}E when the content is less than the transition content. It can be concluded that ΔT{sub}E is not related to carbon activity but to thedistribution coefficient of element between cementite and austenite.