Self diffusion of Mn in icosahedral Al-Pd-Mn quasicrystals

Abstract

This paper presents an experimental study on Mn diffusion in the icosahedral quasicrystal Al69.9Pd20.5Mn9.6. The diffusion was measured by depositing Mn on the surface and measuring the rate of change in surface composition as a function of temperature by Low Energy Ions Scattering (LEIS), followed an Arrhenius relation from which an activation energy for the diffusion could be derived. The surface composition was monitored over the temperature range of 355K to 575K. Activation energy (0.20 ±0.01) eV has been measured for self diffusion of Mn in icosahedral Al-Pd-Mn. No deviation from Arrhenius behavior was detected in the temperature range covered by the present experiment.