β Scribed by M. V. Klassen-Neklyudova; V. G. Govorkov; A. A. Urusovskaya; N. N. Voinova; E. P. Kozlovskaya
No coin nor oath required. For personal study only.
The stressβstrain curves and the defect structure of corundum single crystals (sapphire and ruby) were studied. The influence of impurity (Cr) presence, crystallographic orientation, temperature, and deformation rate was investigated. Chromium makes corundum harder and causes a yield point phenomenon. The yield point was also increased by the transition from 60Β° to 90Β° orientation of the specimens, by lowering the temperature, and by an increase in the deformation rate. In 60Β°βspecimens the deformation occurs by means of gliding on basal planes in γ1120γ and γ1010γ directions. In 90Β°βsamples beside this one gliding in (1010), (1011), (2021) and (2243) is found.
π SIMILAR VOLUMES
Single crystal ice we8 deformed in tension at oonstant strain rates 8t temperetures between -42Β°C end 0Β°C. For shear stresses below 100 pei and nominal atreins less than 25 per aent (startin with BB- grown cry&&), besel slip w8a the prim8ry meohenism of deform8tion. No preferred cry& & ogrephic slip
Strengthening in the early aged state is attributed to a shear of thin a-Mn precipititte particles by dislocations which produces chemical hardening and generates new faulted interfaces inside the manganese particles. Activation energies and volumes have been calculated for this process from the dep