Threshold stress during tensile and compressive creep in AE42 magnesium alloy

摘要

The use of magnesium alloys in engine or powertrain applications is one of the greatest challenges in development of light weight magnesium alloys. Whereas room temperature applications are already in use for a long time for example in steering wheels, inner door frames or steering columns, components with service temperatures of more than 150°C require specific strength and creep resistance. Aluminum and rare earth containing magnesium alloy AE42 is expected to be a candidate for such applications. High creep resistance is attributed to AlRE-precipitates which form during solidification. Tensile and compressive creep tests are performed at temperatures between 150°C and 240°C with applied stresses between 40 and 120 Mpa. In this investigation the influence of direction on the minimum or secondary creep rate is examined. Additional analysis of creep rates in terms of determining deformation mechanisms during creep are investigated in this paper.