Oxidization thermo-dynamics of ignition-proof element and oxides properties in magnesium alloy

The electro-negativities, Gibbs free energy of oxidation reaction and physical properties of some alloying elements and their oxides were compared. It is pointed out that alkaline earth and rare earth elements, especially Be element, are dominant ignition-proof elements of magnesium alloy. RE elements is used to substituting Be and Ca due to high toxicity of Be and be inferior to mechanical properties of the Mg alloy with Ca. The oxidation and ignition temperatures of AZ91 magnesium alloy with somewhat Ce addition were measured. The results show that although the oxidation and ignition temperatures of the alloy are raised, their increasing velocity is slowed with Ce addition increase, increasing by 33°C and 61°C, respectively, with 1% Ce addition, compared with those of the AZ91 magnesium. The advisable Ce addition is about 0.6% for ignition-proof AZ91Mg alloy.

Duke Scholars

Author Zhaohui Wang Pathology