Internal friction behavior of twin boundaries in tensile-deformed Mn–15 at.% Cu alloy

An orientation image microscope was used to characterize the orientation features in a deformed Mn–15 at.% Cu alloy. It was found that twinning and subsequent de-twinning prevailed during the deformation process of the twin bands, which were separately identified as massive and twinning type bands. The 〈111〉 and 〈100〉 fibers steadily developed along the tensile direction as the prestrain increased. The internal friction due to the movement of the twin boundary was investigated using a dynamic mechanical analyzer. It was deduced that the twin-boundary internal friction greatly depended on the arrangement of the twin variants, which can be changed by deformation or a thermal treatment.