Effect of solute atoms on the motion of a low angle tilt boundary

Abstract

Modes of boundary motion in crystals containing controlled amounts of Ag as an alloying element in high-purity Zn crystals were examined. A discontinuous motion found in the alloy crystals at room temperature could be attributed to the diffusivity of solute atoms since such behavior is not observed in the alloy crystals at liquid nitrogen temperature and in the pure crystals at room temperature. A situation similar to the dynamic strain aging seems to have been created around the moving boundary. A further study is necessary to determine the diffusion mechanism. The absence of such discontinuous motion in the pure crystal seems to be due to the lack of sufficient impurity atoms. It appears that the jerky motion observed in pure crystals at room temperature is due to a higher impurity content of approx.100 ppM compared with that of <10 ppM impurity content in specimens exhibiting smooth and continuous motion. (JRD)