Antiphase boundaries in Ni3Al ordered intermetallic—application of the CBED method

The antiphase domain structure in Ni3Al ordered intermetallics with perfect L12 superstructure has been examined. Transmission electron microscopy (TEM) investigations were performed using Jeol JEM 3010 and Philips CM30 microscopes. Conventional TEM studies, convergent-beam electron diffraction (CBED) and high-resolution electron microscopy (HRTEM) were used to elucidate the structure of the alloys. For advanced studies of the nature of antiphase boundaries, the large-angle convergent-beam electron diffraction (LACBED) method was employed. The recognition between symmetry-related and displacive domains can be performed with high accuracy using LACBED and dark-field images, even for nanosized domains.