An X-Ray Topography Study of Dislocation Formation and Motion in Aluminium

Preyield dislocation formation and motion as a function of stress were studied in the stressed state in a zone-refined aluminium single crystal at room temperature using Lang X-ray topography technique. The initial dislocation density was about 500 lines/cm2. Projection topographs show that grown-in dislocations may be sources of stress-induced dislocations. When formed, fresh dislocations move at room temperature at a resolved shear stress σm = (5.7 ± 1.4) p/mm2 = (2.1 ± 0.5) × 10−6 G, G being the shear modulus.