Using synchronized rapid video imaging and calibrated acoustic emission(AE) measurements, a direct correspondence is found between the length of emerging twin and its AE transient response during insitu testing of Mg polycrystals. The detectability limit for twin nucleation in Mg and its alloys is evaluated to be as small as 0.3 mu m or even less.
It is shown that the use of appropriate calibration procedures enables quantitative evaluation of the kinetics of twinning by means of an advanced AE technique.