It was noted that, in metals that yielded as a result of mechanical twinning, the yield stress was a function of the grain size in almost the same way as it was for dislocation glide. However, the sensitivity to the grain size was usually greater. It was shown here that this could be understood, at least partly, in terms of a size-effect that accompanied twinning. Some confirmatory data obtained from a magnesium alloy were presented.

A Rationale for the Strong Dependence of Mechanical Twinning on Grain Size. M.R.Barnett: Scripta Materialia, 2008, 59[7], 696-8