Amorphous alloy composition with high glass-formation ability in the pseudoternary Zr-[IQC-Al 62 Cu 25.5 Fe 12.5 ]-[DQC-
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o-Dahlborg and J.M. Dubois LSG2M, CNRS-UMR7584, Ecole des Mines, Parc de Saurupt, 54042 Nancy Cedex, France
Zukun Hei Institute of Material & Technology, Dalian Maritime University, Dalian 116024, People’s Republic of China
P. Weisbecker LSG2M, CNRS-UMR7584, Ecole des Mines, Parc de Saurupt, 54042 Nancy Cedex, France
Chuang Dong State Key Laboratory for Materials Modification & Department of Materials Engineering, Dalian University of Technology, Dalian 116024, People’s Republic of China (Received 5 January 2003; accepted 9 April 2003)
A pseudoternary alloy system was constructed by combining icosahedral quasicrystal (IQC), decagonal quasicrystal (DQC), and Zr into one alloy system. Different proportions of Zr were added into pseudobinary alloy IQC80DQC20 (in wt.%). The structural evolution in these alloys is discussed. An amorphous alloy composition was found in this system. Melt-spinning amorphous alloy was produced in this composition. Through differential scanning calorimetry experiments, the amorphous alloy exhibited a high glass-forming ability comparable to that of the Inoue alloy Zr65Al7.5Cu17.5Ni10. I. INTRODUCTION
If the existence of icosahedral order to interpret the structure of metallic glasses, or amorphous metallic materials, was for a long time not widely accepted and the subject of great controversy, the strong relationship between amorphous and quasicrystalline phases via the icosahedral order has now become an important issue since new families of metallic glasses can be produced in large dimensions.1 These metallic glasses are mostly multicomponent alloy systems containing more than three elements with significant atomic size differences. One of the structural characteristics of these alloy systems is their highly dense packed atomic configurations and the unambiguous existence of polyhedra such as icosahedra in their structures. Among these systems, the Zr-based amorphous alloys are of high interest because of their good glass-forming ability and large supercooled liquid region.1
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The use of icosahedral order in the interpretation of amorphous metallic structure can be traced back to some years before the production of the first amorphous metallic materials in 1956–1960 by different groups. Detailed study on the amorphous structure by Frank2,3 indicated that an icosahedral cluster is an energetically stable polyhedron present in many multi-element systems. Later, the interpretation of the structural results from amorphous metallic material, so-called “metallic glasses,” via icosahedral models has been reported by several authors for different simple systems (e.g., for Ni81P194 or more generally for A2B alloys,5 where A ⳱ Co, Fe, Cu, or Ni and B ⳱ Zr or Y). More recently, the formation of stable or metastable icosahedral quasicrystals (IQCs) during the crystallization of metallic glasses has been observed by several authors6,7 in different Zrbased systems with compositions Zr 63 Cu 25 Al 12 , Zr65Cu17.5Ni10Al7.5, Zr69.5C
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