Formation of nano-sized Ti68Fe26Si6 icosahedral quasicrystalline phase by rapid quenching and mechanical alloying

Investigation using rapid quenching (RQ) and mechanical alloying (MA) were conducted to produce Ti68Fe26Si6 icosahedral quasicrystals. Subsequent heat treatment was performed on both rapidly quenched ribbons and mechanically alloyed powders in a vacuum furnace under various heat treatment conditions of temperature ranging from 440 to 900 degreesC with a constant heating ra te of 10 degreesC/min and holding time up to 30 h. The amorphous phase of T i68Fe26Si6 ribbon was successively achieved by RQ for the first time from t he present investigation. During the heat treatment, the icosahedral quasic rystalline phase was transformed from the melt-spun amorphous ribbon at the glass transition temperature of 430 degreesC and remained up to approximat ely 520 degreesC. The quasicrystalline phase, however was somewhat difficul t to be obtained from heat treatment of the Ti68Fe26Si6 powder milled for 5 h under the present experimental conditions. (C) 2001 Elsevier Science B.V , All rights reserved.