Diffraction contrast of small point-defect agglomerates as studied by transmission electron microscopy (TEM)

Point Defect Agglomerates (PDA) are frequently observed in particle-irradiated or quenched metals. The sizes of the PDA are often so small that their shape cannot be resolved directly with the electron microscope. In the paper methods are outlined by which the shape (cavities, Frank dislocation loop or perfect dislocation loop) and nature (clusters of vacancies or interstitials) can be determined by means of an electron microscopical analysis.