Age Strengthening of Gray Iron - Kinetics Study
Kinetics of gray cast iron strengthening at room and elevated temperature (100°C, 182°C and 285°C) were studied using 100 specimens cast from one industrial heat of gray iron. Tensile strength and Brinell hardness was measured during age strengthening. Peak aging was observed at shorter times for higher temperatures and over-aging was observed at 182°C and 285°C. Statistically significant data was used for evaluating aging kinetics and the determination of activation energies for precipitation. Tensile strength-temperature-time curves were described using Arrhenius and Avrami-Johnson-Mehl kinetics and an attempt was made to create a predictive model for age strengthening in gray iron. Earlier literature and a current study with another foundry indicate improvement of machinability with aging. The proposed model will help in optimizing the process for maximum tool life.
V. Richards et al., "Age Strengthening of Gray Iron - Kinetics Study," AFS Transactions, American Foundry Society (AFS), Jan 2008.
Materials Science and Engineering
Article - Journal
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