Effects of Additions of Magnesium and Aluminum on the Graphite Morphology and Mechanical Properties of 3.6wt.%C-2.5wt.%Si Cast Iron Poured into Shell Stack Mold

The effects of addition of magnesium only and the simultaneous addition of magnesium and aluminum on the graphite morphology of the cast iron with the composition of 3.6wt.% and 2.5wt.%Si poured into shell stack mold were investigated. The nodularity and mechanical properties of the specimen with smaller cross-section were higher than those with langer one, when copper was not added. When the magnesium only was added, the nodularity was decreased with decreased residual magnesium content and the C. V, graphite was obtained with the magnesium content in the range of 0.010~0.015wt.%. When the magnesium and aluminum were added together, the nodularity was decreased with decreased residual magnesium and increased aluminum contents. When copper was added, the volume fraction of pearlite in the matrix, strength and hardness were higher and elongation was lower for specimen with smaller cross-section. The volume fraction of pearlite, strength and hardness were increased and the elongation was decreased with increased copper content for the specimen with C, V, graphite.

쉘 스택 주조 3.6wt.%C-2.5wt.%Si 주철의 흑연 형상과 기계적 성질에 미치는 마그네슘 및 알루미늄 첨가의 영향