Title: | The thermal stability and mechanical behaviors of Zr-Cu-Ni-Ti-Be bulk metallic glasses |
Authors: | Tsau, Chun-Huei Wu, Chih-Chung Wu, Shyue-Sheng |
Contributors: | 化材系 |
Keywords: | Zr-Cu-Ni-Ti-Be activation energy crystallization elastic modulus oxidation resistance thermal stability |
Date: | 2007 |
Issue Date: | 2009-11-16 11:15:15 (UTC+8) |
Abstract: | Four compositions of Zr-Cu-Ni-Ti-Be bulk metallic glasses with 3 mm in thickness were made by arc melting and die casting processes. The transformation temperature and activation energies of T-g and T-x points of these alloys were examined and calculated, also the hardness and high-temperature elastic modulus of these alloys were analyzed. Results revealed that the increasing of Be-content could increase both of the T-x and Delta T (Delta T= T-x1 - T-g). T-x1 increased from 640 to 691 K and the Delta T increased from 24 to 61 K while the Be-content increased from 11.9 to 27.5 at.%. These exhibited that increasing the Be-content resulted in increasing the glass formability of the alloys in the present study. The activation energies of Zr38.5CU15.25Ni9.75Ti16.5Be20 had a lowest value of 165 kJ/mol among these metallic glasses. Also, increasing the Be-content could enhance the oxidation resistance. In addition, the bulk metallic glasses with the Be-content more than 20 at.% would decrease their high-temperature thermal stabilities. The results showed that the Zr-Cu-Ni-Ti-Be alloys with more than 20% of Be-content would crystallize while they annealed at elevated temperature for several hours, even though the annealing temperatures were lower than the T-x point. (c) 2006 Elsevier B.V. All rights reserved. |
Relation: | JOURNAL OF MATERIALS PROCESSING TECHNOLOGY Volume: 182 Issue: 1-3 Pages: 257-261 |
Appears in Collections: | [化學工程與材料工程學系暨碩士班] 期刊論文
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