Since the start of this decade, Zanardi Fonderie has also been producing isothermal ductile iron (IDI), a material studied and patented by the company, obtained by heat treating ferritic spheroidal graphite iron. Isothermal ductile iron (IDI) acquires mechanical properties making it particularly suited to the production of very thick components requiring high static strength and good fatigue behaviour.
High-performance mechanical applications in austempered ductile iron (ADI), spheroidal graphite iron (GJS), and isothermal ductile iron (IDI)
Zanardi Fonderie S.p.A. has decided to focus its production on these three materials – austempered ductile iron (ADI), spheroidal graphite iron (GJS), and isothermal ductile iron (IDI) – due to their mechanical properties and the benefits they offer to designers of components for the agricultural sector and earth moving sector, for the railway sector and forestry sector, as well as for applications such as reducers, off-road and on-road vehicle suspensions, hydraulic and fluid-power components. The decision to concentrate mainly on austempered ductile iron (ADI) and invest in the development of an internal division dedicated to austempering heat treatment, is linked to its excellent mechanical properties, including:
- fatigue behaviour
- lightness
- good machinability
- wear resistance.
The ample design freedom afforded by austempered ductile iron in the development of mechanical components makes it a valid alternative to the most well-known and commonly used hardened steels.
Track axle for combine harvester in austempered ductile iron ADI: the Zanardi Fonderie case history 
https://zanardifonderie.com
Among the many successful mechanical applications developed in recent years by Zanardi Fonderie for important global players, one of the most interesting is the case history of the conversion of a track axle for combine harvesters from forged steel (42CrMo4V + Hardened) to a casting in austempered ductile iron ADI1050-6. The track axle for combine harvesters is a very important component because it connects the two tracks on the right and left side to the frame of the combine harvester, supporting the weight of the agricultural vehicle. This Zanardi Fonderie case history highlights the opportunities for improvement in terms of performance, lightness, and cost reduction achieved by designing (or re-designing) a component in austempered ductile iron (ADI). In this case, the client opted for a change of material precisely to reduce the weight of the components and contain production costs. Using a casting in austempered ductile iron (ADI), in replacement of the previous solution in 42CrMo4V forged and hardened steel, it was in fact possible to obtain a 22% reduction in weight with consequent benefits in terms of vehicle consumption, less material waste during production, and reduced mechanical machining costs, which led to an overall reduction of the total cost.
Thanks to an efficient Supply Chain Management service, Zanardi Fonderie supports clients from the design stage through to the finished product
Zanardi Fonderie is a single point of reference for the design, production, and delivery of unfinished or mechanically machined components. The case history of the track axle for combine harvesters described above, is a perfect example. Zanardi Fonderie supported the client from the re-design of the track axle from a component in steel to a component in austempered ductile iron ADI, offering its design services to best optimise the form. Once the project was defined, Zanardi Fonderie immediately managed – and continues to do so – the entire supply chain: from the casting of the cast part in ADI to the austempering heat treatment, up to the mechanical machining, which was similarly managed internally, and finally the delivery of the finished product directly to the client. A reorganised company structure today manages the entire Zanardi Fonderie supply chain, ensuring interfacing between all departments of the company’s integrated internal process – foundry, austempering heat treatment, deburring, and mechanical machining – and the large network of external suppliers, to deliver a finished, ready-to-use product to the client. Zanardi Fonderie celebrates its ninetieth anniversary by continuing to work with the same spirit that has forever set it apart, looking to the future and focusing on technological innovation, customer service, research, and quality processing of austempered ductile iron (ADI) and ductile iron in general.
