Inoculant Steel Casting
Inoculant steel casting can promote graphitization, reduce the tendency of white mouth, improve the shape and distribution of graphite, increase the number of eutectic groups as well as refine the matrix structure. It has good effect in a short time(about 5-8minutes) after he incubation process. Inoculant steel casting has various applications in metallurgy, machinery, additives and other industries. And it has good processing ability for harmful elements such as sulfur and phosphorus.
Inoculation treatment refers to adding a small amount of other substances to the liquid metal during the solidification process to promote nucleation, inhibit growth and achieve the purpose of refining the grains. Generally, the addition of additives to steel casting iron is called incubation; adding an additive to a non-ferrous alloy is called metamorphism. Essentially, the inoculation treatment mainly affects nucleation and promotes grain liberation; However, the metamorphism treatment is to change the growth mechanism of the crystal (inhibition of growth) to affect the crystal morphology.
Inoculant for casting iron inoculation treatment has little effect on the chemical composition of cast iron with a small amount of addition and has a great influence on its micro structure. Therefore, inoculant steel casting can improve the mechanical properties of gray cast iron and has a significant effect on its physical properties. Good gestation treatment has the following effects:
- Eliminate or reduce the tendency of white mouth;
- Avoid excessively cold tissue;
- Reduce the wall thickness sensitivity of the cast iron parts, so the difference in micro structure between the thin and thick section of the casting is small, and the hardness difference is also small;
- Conducive to eutectic nucleation, so the number of eutectic groups will increase;
- The shape of the graphite in the cast iron is mainly a fine and evenly distributed type A graphite, therefore, inoculant steel casting can improve the mechanical properties of the cast iron.