Creep of Reinforced and Unreinforced AZ91 Magnesium Alloy

摘要

Constant stress tensile creep tests were conductedat temperatures 423 and 473 K on an AZ 91 (Mg- 9 wt percentAl – l wt percent Zn) alloy reinforced with 20 volume percentA1_2O_3 short fibres and on an unreinforced AZ 91 matrixalloy. In essence, the creep resistance of the reinforced materialis shown to be considerably improved compared to the matrixalloy. The minimum creep rate for reinforced specimens is twoto three orders of magnitude less than that of unreinforcedspecimens under the same loading. The creep life of thecomposite is an order of magnitude longer than the unreinforcedalloy. By contrast, the presence of the reinforcement leads to asubstantial decrease in the creep plasticity.