Spheroidizing is a highly effective annealing process that improves the machinability, toughness, and ductility of high-carbon steels and tool steels by converting carbide particles into a spherical shape. This process requires precise control of temperature, soaking time, and cooling rate to achieve the desired microstructure. This slow cooling process is key in forming the spherical carbide particles. The slower the cooling, the more uniform the structure and carbide shape will be.