Comparative investigation of microarea quasilattice parameters of Al–Si–Mn and Al–Cu–Fe icosahedral phases using HOLZ line patterns

Abstract

Some differences between the higher-order Laue zone (HOLZ) line patterns of A176Si4Mn20 and A165Cu20Fe15 icosahedral phases (I phases) have been observed. These differences originate from the fact that A176Si4Mn2o belongs to a simple icosahedral quasilattice whereas A165Cu20Fe~5 belongs to an ordered face-centred icosahedral quasilattice, and from the minor difference in their quasilattice parameters. By computer simulation of these HOLZ line patterns using a 'standard' quasilattice parameter of 0.460 nm for the I phase of Aly6Si4Mn2o, the quasilattice parameter of the I phase of A165Cu2oFe~5 has been determined to be 0.8966 nm.