What effect does magnesium play in nodular cast iron?
Magnesium is played by spheroidizing.Nodular cast iron is added a certain amount of spheroidizing agent (magnesium or rare earth magnesium alloy) to the paste before casting, so that all or most of the carbon is spherical graphite and is distributed on the base.
The role of magnesium as spheroidizing agent used in iron spheroidizing treatment, promote water ink is made of iron, carbon in liquid iron spherical graphite precipitation.
Magnesium can be graphite precipitated in spherical form.But the specific mechanism is not clear, and now it is still debated in the academic circles.In addition, magnesium and sulfur generate MgS, which removes S from molten iron, which impedes the formation of spheroidal graphite.Therefore, Mg has two functions to eliminate the influence of S on Nodular Iron and promote the precipitation of graphite in spherical form.
