An Evaluation Model for the Nodule Count of Graphite Particles in Ductile Iron Castings

Abstract

An evaluation model on the nodule count of graphite particles in ductile iron castings was developed based on a series of orthogonal experiments. The model is proposed for evaluating the count of graphite particles in ductile iron castings with different carbon equivalent (CE), local solidification time (t_s), and maximum undercooling. According to the nodule count spacial distribution theory, the graphite nodule density N_v equals nuclei density after solidification. The measurement of N_A values were carried out on experimental ductile iron castings designed according to the orthogonal principles. N_v was calculated from area densities N_A using Owadano rules. The results indicate that the count of graphite particles has a close relationship to CE, t_s and instead of one of these three parameters.