Aging effects of dodecagonal quasicrystal formed in Mn-Cr-Ni-Si alloys

The formation of Mn-Cr-Ni-Si dodecagonal quasicrystal has been studied at 600 and 700 C. The growth process of the quasicrystal from as-cast beta-Mn phase was explained by Johnson-Mehl-Avrami equation. In order to evaluate structural quality of the quasicrystal, distortion in the diffraction pattern observed along the 12-fold axis was analyzed. This analysis indicated that the aging at 600 C for 100 h is the best condition to synthesize the quasicrystal.