Size-dependent thermal oxidation kinetics in Sm2(Co, Fe, Cu, Zr)17 alloy powder

This study investigates the interrelationship between the oxide growth kinetics and the microstructural changes induced by dry, thermal oxidation in Sm<inf>2</inf>(Co, Fe, Cu, Zr)<inf>17</inf> alloy powder (of varying particle sizes and compositions). Whereas, model-free iso-conversional methods are used to determine the kinetic-triplets during the non-isothermal oxidation stage, power-law dependent kinetic model is considered during the entire oxidation process to calculate the reaction order, rate constant and the apparent-activation energy. A distinctly different oxide growth kinetics, with strong dependency on the initial particle size(s) and the alloy composition-induced oxide microstructure is seen here.