Long-period superstructures in Cu3±xPd

作者：Dirk Broddin, Gustaaf Van Tendeloo, Joseph Van Landuyt, Severin Amelinckx, Richard A. PORTIER, Michel Guymont, Annick Loiseau · 发表于：Philosophical magazine. A/Philosophical magazine. A. Physics of condensed matter. Structure, defects and mechanical properties · 年份：1986 · DOI：10.1080/01418618608240723 · 被引用次数：87 · 研究领域：nanoparticles nucleation surface interactions、Theoretical and Computational Physics、Metallurgical and Alloy Processes

The one- and two-dimensional long-period superstructures in Cu3Pd are analysed by means of high-resolution electron microscopy and electron diffraction. Minor, but nevertheless significant, modifications of the phase diagram are suggested from detailed microstructural observations. The half-period M varies not only with composition but also with temperature. A systematic decrease in M with increasing temperature has been established. At low Pd concentrations the M values are incommensurate; this is confirmed by structural imaging. At high Pd concentrations, M decreases and locks in at simple commensurate values such as 4·5, 3·5, or 3. A comparison of high-resolution images of the periodic antiphase boundaries of the one-dimensional long-period superstructure with computer simulations seems to indicate that the diffuse character of the boundary images is due to compositional disorder along the boundaries.