Abstract
In this study, the effect of powder characteristics on the reactivity of Mg powder with water was examined through thermal analysis and chemical reaction kinetics analyses. Mg powders with different particle size distributions were prepared via sieving; specific surface area analysis revealed that the specific surface area of these Mg powders linearly correlated with their inverse equivalent volume diameter. An exothermic reaction between Mg and water, which generates magnesium hydroxide, was analysed using a Calvet calorimeter, and the onset temperature of the reaction was found to decrease with a decrease in the particle size of the Mg powder. Chemical reaction kinetics analysis revealed that the apparent activation energy and natural logarithm of the pre-exponential factor decreased with specific surface area, and reaction rate constant linearly correlated with the specific surface area or inverse equivalent volume diameter. The results of this study can be used to explore the problem of aging and safety of Mg.