Investigation on Isothermal Spheroidizing of Carbides in Hot Deformed Medium Chromium Cast Semi-steel

The spheroidizing behaviors of carbides formed from deformation at high temperature in medium chromium cast semi steel had been studied during isothermal spheroidizing process.The results showed that the carbides grown under the way that the bigger carbide particles merged the smaller ones or short bar like carbide separated and the bar ends resolved to spheroidize itself.The carbide size increased as its number decreased gradually,when the isothermal spheroidizing temperature is at 650℃,the growth speed of spherical carbide could be expressed by the experimental equation:V r=1 2274×10 -3 (0 323+0 0062t) 2( μm /min)