بررسي اثر جوانه زايي كاربيد سيليسيم بر ريز ساختار چدن نشكن

The Effect of SiC Inoculation on the Microstructure of Ductile Iron

This study focuses on the effects of inoculation on the microstructure of ductile iron (nodurality, nodule count per unit area, the amount of ferrite and pearlite and variation of hardness). 0.1, 0.2, 0.3, 0.4, and 0.5 weight percent of silicon carbide added to ductile iron in order to nomination inoculantsʹ s optimum amount. Also 0.5 weight percent of ferrosilicon for achieving desired mechanical properties have been used. Observation and experiments on the basis of complete solution at the time and temperature of inoculation treatment showed that adding 0.3% of silicon carbide as inoculants to ductile iron in compare with adding 0.5% ferrosilicon has a more positive effect on morphology and distribution of graphite nucleus in microstructure. More efficiency of SiC in inoculation is due to formation of clusters of dispersed carbon I melt that has a similar crystallography structure with graphite and these ease inoculation. Results also showed that decreasing cooling rate cause to increasing solidification time and as a result the effect of silicon carbide on inoculation will be decreased