Crystallographic Dependence of a Dislocation Etch for Zinc Single Crystals

Abstract

Additional observations have been made on the crystallographic dependence of a dislocation etch for zinc single crystals originally developed by Brandt, et al. The original work confirmed that the etch technique was suitable for revealing basal and nonbasal dislocation intersections with {1010} prism planes. A new set of crystal surface orientations has been found where etch pits are revealed. A 2 in. diameter hemispherical crystal of 99.999 per cent purity zinc was etched and etch pits were found on all surfaces located between 3° and 12.2° to the [0001] axis. Figure 1 shows the regions of good, marginal and poor etching. Attempts to etch the (0001) basal plane were generally unsuccessful although it was found that by etching freshly cleaved surfaces some etch pits were revealed that were obviously associated with twinning damage. A fresh surface was produced by quenching a specimen in methanol immediately after cleaving it in liquid nitrogen. No further attempts were made to etch (0001) planes because it is generally undesirable to subject large specimens to the thermal strains involved in the quenching process.