Abstract
The effect of centreless grinding and abrasion of zone‐melted molybdenum single crystals on their dislocation structure is investigated by thin‐foil transmission electron microscopy. The observations reveal that typical dislocation arrangements result from the mechanical pretreatment of the crystals. It is possible to distinguish between grown‐in dislocations and those configurations introduced by grinding. In addition some etch‐pit studies are carried out to test the reliability of this method. The results are discussed in relation to adequate preparing tensile specimens and correct analysing electron micrographs.