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The TVR Tuscan Speed Six, (produced by TVR Engineering in Blackpool, England) is a high performance automobile, by any measure. This low volume sports car weighs 1,100 kg (2,420 lbs) and is powered by a 4-litre in-line six-cylinder engine that develops over 350 bhp and 310 ft-lb of torque. TVR Engineering selected an Austempered Ductile Iron (ADI) crankshaft for its combination of low cost, low weight and high torsional strength. Not since Ford dabbled with ADI in its race cars in the 1980's has a manufacturer chosen ADI for its crankshafts. Although virtually all the major automotive producers and the Motor Industries Research Association (MIRA) have investigated ADI for use in crankshafts, this is the only known production application of ADI crankshafts in automobiles. ADI presents a useful set of properties for the design engineer. With ever increasing specific power requirements for new engine designs, new material/process combinations for engine components are being explored.

Austempered cast irons have a unique microstructure (ausferrite) that provides for excellent wear properties. This paper will examine the available data in the literature on wear in several modes: abrasive wear, adhesive wear (frictional or sliding and rolling), and erosive wear. Additional wear data, including that from competitive materials as well as from private communications, will be presented along with examples of applications of austempered ductile cast irons where wear properties are of concern

Austempered Ductile Iron was first commercially applied in 1972. By the mid 1970's it had found its way into Chinese Military trucks and into commercial truck applications in Europe. By 1978, austempered ductile iron had been applied to light cars and trucks in the US. Today, it is estimated that over 50,000 tons per year of austempered ductile iron components are installed in cars and trucks world-wide. That production appears to be growing at a rate of exceeding 10% per year. As a family of materials, austempered ductile iron capably addresses the issues of weight, strength, stiffness, noise, cost and recyclability. From the first differential gear sets installed by General Motors in 1978, to light-weight truck-trailer wheel hubs, to high performance automobile suspensions, austempered ductile iron has found itself in many unique applications. This paper will review those applications, the reason(s) for the conversions, and the performance of those components.