A lecture given by John Speer, at the Adventures in the Physical Metallurgy of Steels (APMS) conference held in Cambridge University. The quench and partitioning process involves partial transformation to martensite, followed by an increase in temperature to permit the excess carbon to partition into the residual austenite. The quenching and partitioning (Q&P) concept was first introduced about a decade ago, to utilise carbon in as-quenched martensite to stabilise retained austenite and thereby enhance the mechanical properties. This presentation will provide an update of advancements made in understanding important aspects of physical metallurgy and microstructure development, within the authors laboratories and elsewhere, which have led to interest in Q&P as a potential route for producing commercial steels in volume. A variety of applications have been explored in Q&P laboratory investigations. Initial industrialisation has focused on automotive sheet steels, and substantial activity is now underway to meet aggressive near-term targets for vehicle lightweighting using Q&P steels or other novel approaches to generate microstructures with enhanced austenite fractions. The current status of some of these efforts will be reported. |