The Advantages of Investment Casting Technology and the Benefits of Ductile Iron S ince ductile iron was developed in the 1940's, this remarkable metal has proved its value in tens of thousands of engineering and casting applications. Ductile iron is created by an alloying process which converts the crack-promoting graphite flakes of gray iron into nodules. With this microstructural transformation, the metal acquires superior ductility, elongation characteristics, and machinability. The ductile iron family offers the design engineer a unique combination of strength, wear resistance, fatigue resistance, and toughness, as well as excellent ductility characteristics. In all its grades, ductile iron exhibits mechanical properties that make it an ideal alloy for investment casting.
Ductile iron represents the fastest growing segment of the iron market.
It is a cost-effective substitute for carbon and low alloy steels, and in some applications, ductile iron can even outperform steel. By applying the two-stage heat treatment process known as austempering, the metal acquires even more advantageous properties, challenging the performance of medium grades of steel. The investment casting process offers superior quality and economics. An original sand-cast part is shown on the left. The converted ductile iron investment casting on the right provided the customer with better quality, near net shape, improved surface finish, elimination of most costly machining, reduction in rejected parts and significant cost savings.