STUDY OF DISLOCATIONS IN COPPER BY WEAK BEAM, STEREO, AND IN SITU STRAINING TEM

摘要

Conventional transmission electron microscopy (TEM) has been an invaluable tool for verifying and developing dislocation theories since the first direct observations of dislocations were made using a TEM in the 1950s. Several useful techniques and technological advancements have been made since, helping further the advancement of dislocation knowledge. The present paper concerns two studies of dislocations in copper made by coupling several of these techniques, specifically weak beam, in situ straining, and stereo TEM. Stereo-TEM coupled with in situ straining TEM was used for tracking 3D dislocation motion and interactions in low dislocation density copper foils. A mechanism by which dislocations in a pileup bypass a dislocation node is observed and discussed. Weak beam TEM is used in conjunction with stereo-TEM to analyze the dislocation content of a dense dislocation wall (DDW).