An efficient and reliable method for characterizing the nature of stacking fault tetrahedra in f.c.c. metals using electron microscope diffraction image contrasts is presented. By using the 220 reflection, and thereby eliminating the contrast from overlapping stacking faults, one can differentiate between intrinsic-type stacking fault tetrahedra due to lattice vacancies and extrinsic type due to interstitial atoms. The validity of the method is examined by the observation of vacancy-type stacking fault tetrahedra in quenched metals, and by the observation of interstitial-type faulted dislocation loops. Stacking fault tetrahedra introduced by plastic deformation, electron irradiation, neutron irradiation and ion irradiation are all confirmed to be vacancy type. It was found that interstitial-type stacking fault tetrahedra do not exist.
|ジャーナル||Philosophical Magazine A: Physics of Condensed Matter, Structure, Defects and Mechanical Properties|
|出版ステータス||Published - 1989 3|
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