抄録
A refined technique for etch-pitting in copper crystals has been developed in order to distinguish between different kinds of dislocations and to produce stainless, well-defined etch-pits in multiple etching. The technique has been applied to study the configurations of grown-in dislocations emerging on a {111} crystal surface of well-annealed copper crystals. The results obtained are as follows.
(1) Two etchants (modified Young’s etchant), [A] (FeCl3·6H2O:28 g, HBr:2.1 cm3, HCl:120 cm3 and H2O:80 cm3) at the working temperature 281.5 K and [B] (FeCl3·6H2O:43 g, HBr:4.3 cm3, HCl:100 cm3 and H2O:100 cm3) at the working temperature 293 K, are found most suitable for distinction between edge and screw dislocations and between opposite edge dislocations, respectively. (2) Multiple etching can be successfully performed by the use of intermediate etching in a solution of chromic acid and HCl. (3) Grown-in dislocations both in edge orientation and in near-screw orientation frequently have large super-jogs as high as 40∼60 μm. (4) Grown-in dislocations in a surface layer within a depth of 20 μm are perpendicular to the trace of the slip plane on the surface, but in the interior beyond that depth they are often bent on individual slip planes. (5) Threefold nodes occasionally exist very close to the as-annealed surface. (6) Edge dislocation dipoles have been observed on the as-annealed surface. (7) Ratio of grown-in dislocations in 30°-screw orientation to those in edge orientation is about 2 in crystals with a dislocation density higher than 5×103/cm2, but it decreases to about 0.7 in crystals with a dislocation density of 5×102/cm2.
