Cast iron in combination with nodular graphite is known as ‚Ductile cast iron’. Its graphite structure causes qualities similar to those of non-alloyed steel castings. Its carbon content is significantly higher than 2%.
Like grey cast iron ductile cast iron can be very well machined, but its weldability is limited. Because of its high level of strength this group of materials is, amongst other things, used for vehicle parts such as brake discs, steering knuckles, connecting rods, wheel hubs and gear levers.