Bulk mechanical properties of quasicrystals

摘要

Elastic moduli,anharmonicity,hardness and high temperature plastic behavior of icosahedral and decagonal quasicrystals are reviewed.Elastic properties are discussed in relation to the bonding nature of the quasicrystals.The plastic deformaiton behavior at high temperatures is discussed based on the characteristics of hte dislocation mechanism in the quasiperiodic lattice.A Peierls potential,a phason relaxation and a dragging stress due to productin of a defect field are considered as the controlling factors for the thermally activated dislocation glide; a dislocation in quasiperiodic lattice is accompanied not only by the elastic (phonon) strain field but also by the phason strain field which is difficult to be relaxed completely with the disolcation glide.