Evolution of inoculation thermal analysis and solidification morphology of compacted graphite iron

Abstract

This paper describes one possible thermal analysis method to anticipate and control the inoculation effect during the solidification of CGI melt. Results show that 0.10–0.45 % ferrosilicon inoculation in the sample cup can promote the solidification morphology of the melt to evolve from hypoeutectic to eutectic or even low hypereutectic. With the stepwise more inoculant additions, the minimum eutectic temperature difference for the two stepwise additions decreases. The inoculation saturation value is basically reached in the 0.30 % inoculant sample cup, of which the minimum eutectic temperature increase is 5.3 ◦ C compared with that of the original melt. When inoculated, the carbon potential and eutectic inoculation potential of the melt are improved. At 0.45 % inoculant, the melt can solidify in the form of low hypereutectic. In this case, the nodularity rate increases significantly to 34 %, and large particles of graphite nodule appear.