The high-temperature compressive deformation behavior of icosahedral and decagonal quasicrystals was reviewed. In icosahedral quasicrystals, the true stress versus true strain relationship exhibited a pronounced yield-drop, followed by gradual softening towards a minimum at a true strain of about 0.5. This then changed to hardening at higher strains. The yield and flow stresses were quite sensitive to the temperature and the strain rate. In

decagonal quasicrystals, the yield stress depended weakly upon orientation in spite of its anisotropic structure. For both types of quasicrystal, the yield stress was higher in higher-quality samples. The deformation mechanism of the quasicrystals was explained in terms of dislocation glide governed by the Peierls mechanism. This mechanism, in quasicrystals, differed from that in crystals in that dislocation glide was accompanied by a phason strain relaxation and the Peierls potential was not periodic but quasi-periodic.

Deformation Mechanism of Quasicrystals. S.Takeuchi, K.Edagawa, R.Tamura: Materials Science and Engineering A, 2001, 319-321, 93-6