The role of rare earth in nodular cast iron
Rare earth can make the graphite spheroidizing. Since h. Morrogh nodular cast iron using cerium, first has many people research the spheroidizing behaviors of various rare earth elements cerium found is the most effective element of spheroidizing, other elements also have varying degrees of spheroidizing ability.
Combined with national conditions, the spheroidizing effect of rare earth in China a lot of research work, found that rare earth elements on the commonly used nodular cast iron component (C3.6 ~ 3.8 wt %, Si2.0 ~ 2.5 wt %), it is difficult to obtain with magnesium nodular cast iron as a complete uniform spherical graphite; And, when the amount of rare earths, there will be various abnormal shape of the graphite, chilling tendency also increases, but, if it is high carbon eutectic composition (C > 4.0 wt %), rare earth residue was 0.12 ~ 0.15 wt %, ?