Search for content and authors |
Self diffusion of Al and Mn in icosahedral Al-Pd-Mn quasicrystal |
Feridoun Samavat |
Physics Department, Bu-Ali sina university, Mahdiyeh St., Hamedan Hamedan, Iran |
Abstract |
Self diffusion of Al and Mn in icosahedral Al-Pd-Mn quasicrystal Feridoun Samavat a,b, Bruce V. King a, D. John O’Connor a a School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, New South Wales, 2308, Australia b Department of Physics, Bu-Ali Sina University, Hamedan, Iran AbstractThe self diffusion of Al and Mn in a single grain icosahedral Al69.9Pd20.5Mn9.6 quasicrystal has been determined by a Low Energy Ions Scattering (LEIS) technique. LEIS technique has been able us to focus on the dynamics of concentration profiles at the surface and between the surface layers. The diffusion was determined by depositing the different elements (Al, Mn) on the surface and measuring the rate of change in surface composition as a function of temperature by LEIS, followed an arrhenius relation from which an activation energy for diffusion could be derived. The surface composition was monitored over the temperature range of 355K to 675K for Al and 355K to 575K for Mn. Activation energies of 0.17±0.02 eV and 0.20±0.01 eV have been measured for self diffusion of Al and Mn in i-Al-Pd-Mn respectively. No deviation from Arrhenius behavior was detected in the temperature range covered by the present experiments. From the low values of activation energy we propose that this range of diffusion is phason related, reflecting the specific nuture of the icosahedral structure. Keywords: Diffusion; Aluminum; Palladium; Manganese; Quasicrystals; Low Energy Ion Scattering (LEIS); Al-Pd-Mn; Metalic surfaces . |
Legal notice |
|
Related papers |
Presentation: Poster at Joint Fith International Conference on Solid State Crystals & Eighth Polish Conference on Crystal Growth, by Feridoun SamavatSee On-line Journal of Joint Fith International Conference on Solid State Crystals & Eighth Polish Conference on Crystal Growth Submitted: 2007-01-14 16:36 Revised: 2009-06-07 00:44 |