The development of ADI and IDI in Italy

Abstract

This paper gives the State-of-The-Art of the knowledge of Ductile Iron (DI), Austempered Ductile Iron (ADI) and Perferritic Isothermed Ductile Iron (IDI®), resulting from research programs executed in Italy at Zanardi Fonderie. It gives information about DI, ADI and IDI fatigue properties, notch sensitivity and fatigue properties with un-machined surface. It will be also shown some case studies. The following grades of ADI have been developed: SAE J2477 AD750, ISO 17804 JS/800-10, ISO 17804 JS/900-8 and ISO 17804 JS/1050-6. In recent years, the cost increase of alloying the low hardness grades of ADI has led to a slower rate of growth of new applications, thus, created the opportunity for the invention of Perferritic IDI (Patent pending). The high strength grades of ADI ISO 17804 JS/1200-3, ISO 17804 JS/1400-1 (ISO 17804 JS/HBW400), ISO 17804 JS/HBW450 are also proposed to engineers, with competitive opportunities for machining, integrated into the manufacturing process. One of the key success factors of ADI has been the process integration: design, foundry and heat treatment processes and machining have to be considered as one single process.