Rare Earth Inoculation of Grey Iron Craft

grey ironRare earth inoculation of grey iron craft depends on the adding methods of nucleating agent, mainly including internal inoculation, late inoculation and in-mold inoculation. Because the inoculant is time effective, namely, inoculation effect of inoculant will weaken along with the extension of time, so the time to add nucleating agent is general in the process of grey iron casting or directly put in the casting mold. And it is better to equal the inoculation time with solidification time of the grey iron casting which will improve the effect of inoculation. Thus the general choice about the inoculation type are late inoculation and in-mould inoculation.

Now the inoculation that are commonly used is pour-in method, porous plug method, in-mold processing method, wire injection, blowing process, and tundish method. The pour-in method is the most widely used which has significant effect on the performance of the grey iron.

The instantaneous inoculation, one of the common inoculation methods of grey iron casting, present the best effect. Instantaneous inoculation can significantly improve the organization form of grey iron, and there will be no bulky graphite. while the grey iron cast by ladle inoculation will generate bulky graphite. Therefore instantaneous inoculation can maximize and promote graphite nucleation, but won’t affect the growth of graphite.


Organization and Performance of Grey Iron Casting

Organization of grey iron casting

Ferrite grey iron casting —— fully carry on graphitizing process

Pearlite grey iron casting ——fully carry on graphitizing process of stage 1 and graphitizing process of stage 2,graphitizing process of stage 3.

Pearlite grey iron casting ——fully carry on graphitizing process of stage 1 and graphitizing process of stage 2,hardly carry on graphitizing process of stage 3.

grey iron casting (1)Performance of grey iron casting

Performance of grey iron casting mainly depends on the performance of matrix and quantity, form,size, disposition of graphite, among these , the performance of pearlite matrix and the performance of grey iron casting which is made from graphite is optimal. The range of applications is most extensive.

Tensile strength and ductility of grey iron casting is much more lower than steel has the same matrix.But graphite flake has no influence to the compression strength of grey iron casting.

Grey iron casting has better casting performance and handling characteristics. Graphite has effects of anti-attrition and shock absorption.
Treatment of alteration:

Join alterant in iron liquid before pouring, promote grain refinemen

The passage above talks about parts of organization and performance of grey iron casting.