Abstract
The influence of alloying elements on graphite morphology and cooling curves was studied using Ni-C eutectic alloys. Ninety grams of Ni-C parent alloys, prepared using high purity metals, was melted in an Ar atmosphere at 1500°C and cooled at the rate of 40K/min. Their cooing curves were monitored every 0.1s using a B-type thermocouple located at the center of the samples. The graphite morphologies of the samples were observed using an SEM and optical microscope.
Experimental results showed that spheroidal graphite formed after the crystallization of chunky graphite. This phenomenon completely differed from that of the Fe-C alloys, in which after the spheroidal formation the chunky graphite crystallizes. These results were confirmed by the cooling curves and microstructure.
