Etch Pits at Dislocations in Copper

Abstract

A possible mechanism for the development of etch pits at dislocations in copper by etching in solution is presented, and experiments are described which may substantiate this mechanism. Etchants which will develop pits at clean dislocations on the (111), (100), and (110) faces of copper are described. These etchants are capable of distinguishing between clean dislocations and dislocations with a ``Cottrell atmosphere'' in 99.999% copper. Clean edge and screw dislocations can also be differentiated with these etchants. Some observations concerning the relation of facet structure, developed by etching, to the dislocation structure of the crystal are reported.