N. B. Pugacheva, D. I. Vichuzhanin, S. V. Smirnov, S. T. Kalashnikov, V. S. Chekushkin, N. P. Antenorova, A. A. Pankratov
STUDYING THE CHANGES IN THE STRUCTURE AND PROPERTIES OF A MAGNESIUM ALLOY AFTER OPERATION AND LONG ANNEALING AT TEMPERATURES OF 50 AND 70 °C
The microstructure and mechanical properties of magnesium alloy samples cut out from a shell structure after 20 years' operation in climatic conditions are studied, as well as the effect of subsequent annealing at temperatures of 50 and 70 °C during up to 3000 h on the change in the mechanical properties and the values of electrical resistivity. The magnesium alloy is shown to consist of an α-solid solution of alloying elements in magnesium, a β-solid solution of alloying elements in lithium, and intermetallic compounds of aluminum, zinc, magnesium, manganese and lithium. At the studied temperatures, the aging processes in the alloy proceed extremely inertly, with an insignificant decrease in hardness and unchanged values of electrical resistivity. Changes in mechanical properties are recorded only within the first 1000 hours of annealing at 70 °C.
Keywords: magnesium alloy, microstructure, intermetallic compound, hardness, strength, aging, electrical resistivity