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The usage of forging a preformed, near net shape, compacted and sintered metal powder has been widely accepted since the eighties and is now one of the mainstays for producing Connecting rods in North America. However, its use in Indian subcontinent is limited as its counterpart i.e. conventional steel forging is still the most dominant. Powder metallurgy route has many advantages like good dimensional accuracy; minimum scattering of weight etc. Despite these advantages, the Powder metallurgy process is still not preferred predominantly due to technical (endurance) and infrastructural limitations. This work envisages combining the benefits of powder metallurgy process with the required mechanical properties viz. tensile and fatigue strength alongside design modifications to meet the requirements of a connecting rod for a 2-cylinder diesel engine. The connecting rods met the fatigue life at the required FOS equaling the performance of a conventionally forged connecting rod.

The automotive industry is facing a challenge as efficiency improvements are required to address the strict emission norms which in turn requires high performance downsized, lightweight IC engines. The increasing demand for lightweight engine needs high strength to weight ratio materials. To meet high strength to weight ratio, castings are preferable. However due to strength limitations for critical crankshaft applications, it forces to use costly forgings such as micro alloyed forging steel and Martensitic (after heat treatment) forging steel. To reduce the cost impact, high strength Austempered Ductile iron (ADI) casting is developed for crankshaft applications to substitute steel forgings. Austempered Ductile Iron is having an excellent mechanical properties due to aus-ferritic structure. The improved properties of developed ADI Crankshaft over steel forged crankshaft offers additional weight advantage.