(a) Figure 6. (a) The effect of carbon equivalent on cell27
(b) and (b) nodule count is shown above.28
Table 2. Nucleation Coefficients
Effect of Inoculation Practice
It is well known that a drastic method commonly employed in increasing the cell count in hypoeutectic iron or nodule count in ductile iron is through inoculation. The effects associated with this process depend on: (a) the chemical composition of the cast iron, (b) the amount and type of inoculant, (c) the temperature and time of bath superheating of the base cast iron and (d) the temperature of the inoculation process and the time lapse from the inoculation time moment (fading).
International Journal of Metalcasting/Summer 10
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Type of inoculant—silicon-containing inoculants are effective because they contain small amounts of im- portant elements (Ca, Al, Ba, Sr, La, Ce) since pure silicon and pure ferro-silicon do not inoculate. There are currently a few hundred32
types of inoculants of
varying strengths. An example of the influence of various types of inoculants on cell or nodule count is shown in Fig. 8. In general, Ca levels of roughly 1% in FeSi yield a good cell and nodule count.33 the content of rare earths (RE) should be at an op-
Also, 41
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