Published online by Cambridge University Press: 15 March 2011
This paper investigates the effect of solute in Al alloys on grain boundary character and mobility based on experiments in which individual boundaries migrate under a stored energy driving pressure acquired from prior plastic strain; among those studied are Zr, Fe and Si. A compensation effect is noted for both alloys studied with respect to both temperature and solute content. As supported by the literature, boundaries exhibit a maximum mobility for a 38-39°<111> misorientation in initial annealing experiments; this mobility maximum is asymmetric with a sharp cutoff below 38-39° but a more gradual decrease at misorientations beyond 40°. The presence of a minimum at 38-39° is found at both higher temperatures and higher solute concentrations. A shift in texture dependency with solute and temperature is also observed. This transition from a local mobility maximum to a minimum is discussed within the context of recent developments in solute drag theory.