Structure evolution of EV31 Mg alloy

Abstract Structure modifications and precipitation hardening of EV31 Mg alloy have been monitored by calorimetric measurements (DSC), TEM observations and positron annihilation spectroscopy (PAS). At the early stages of precipitation DSC measurements and TEM observations evidenced the formation of a β″ phase, while the presence of an intermediate β′ is supported by positron data. Overageing is correlated to the formation of an incoherent β 1 phase, which transforms in situ into the equilibrium β precipitate.