Because of the peculiar atomic structure of quasi-crystals, which are neither crystalline nor amorphous, there have been high expectations for their many attractive mechanical properties. Because these quasicrystals have been obtained usually as a powder by a melt-spinning technique and a mechanical alloying (MA) method, except for several stable quasicrystals such as Al-Cu-(Fe, Ru) [1] and Al-Pd-Mn [2], which can be obtained by a slow solidification technique, it has been very difficult to obtain bulk samples of quasicrystalline alloys. Therefore, few studies [3-6] concerning their mechanical properties have been reported. In recent reports, Mg-AI-Zn quasicrystals have been synthesized as a metastable phase by the MA technique [7], and the formation range of quasicrystals and related approximant crystal has been studied [8]. In this letter, we investigated the phase stability under high pressure, up to 5.4 GPa, and suitable consolidation conditions of Mg-AI-Zn alloy quasicrystalline powders using a high-pressure technique. Mechanical properties of the quasicrystalline bulk samples obtained were clarified and compared with those of related crystalline material.
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