Question - Which Of Different Types Of Cast Irons Is Stronger? Is Their Strength Superior To Steels?
Answer -
Generally, steels are considered to have better mechanical properties and ductility. However, there are some types of cast irons like ductile iron, which, in contrast to other types of cast irons, are not brittle. The strength of these ductile irons can be enhanced by controlling their matrix via an austempering heat treatment. This Austempered Ductile Irons (ADI) has very good mechanical properties comparable to those of some grades of steel. However, keep in mind that in spite of lower mechanical properties and being brittle, cast irons have good fluidities and are cheaper than steels.
By the way, there are some special purpose gray and white irons, which are frequently used for special applications like where resistance to corrosion, wear, and heat is required.