Influence of temperature on crystallographic orientation induced anisotropy of microscopic wear in an AZ91 Mg alloy

Herein, the temperature-dependent wear behavior of individual grains of solution treated AZ91 alloy with different crystallographic orientations was investigated. Nanoindentation was employed to measure the hardness and wear of differently oriented grains at 25 degrees C (RT), 100 degrees C and 150 degrees C. Scratching at RT showed strong anisotropy in wear for different crystallographic orientations where the wear resistance of basal orientation was found to be highest, followed by pyramidal and prismatic orientations at RT. At 100 degrees C, the wear anisotropy reduced significantly and at 150 degrees C, the anisotropic behavior was absent. The decrease in anisotropy with temperature can be rationalized by considering the variation in active deformation mechanisms. Additionally, at 100 degrees C and 150 degrees C, dynamic recrystallization was observed and the evolved texture was independent of initial orientation.

Automated summary

The research investigated the temperature-dependent wear behavior of individual grains of solution treated AZ91 alloy with different crystallographic orientations. It was found that the wear resistance showed strong anisotropy at room temperature, but decreased significantly at 100 degrees C and was absent at 150 degrees C. Dynamic recrystallization was observed at higher temperatures and the evolved texture was independent of initial orientation.