Influence of similar atom substitution on glass formation in (La-Ce)-Al-Co bulk metallic glasses
Influence of similar atom substitution on glass formation in (La-Ce)-Al-Co bulk metallic glasses
复制标题
相似原子取代对(La-Ce)-Al-Co块状金属玻璃中玻璃形成的影响
DOI：
10.1016/j.actamat.2007.02.026
复制
发表时间：
2007-06-01
期刊：
影响因子：
9.4
通讯作者：
Zhang, Tao
中科院分区：
文献类型：
--
作者：
Li, Ran;Pang, Shujie;Zhang, Tao
通过铜模铸造，确定了La-Al-Co、Ce-Al-Co和(La-Ce)-Al-Co伪三元系大块非晶玻璃的形成范围。通过在(LaxCe1-x)(65)Al10Co25合金(0<；x<；1)中用La逐步替代溶剂CC，采用倾注铸造的方法成功地制备出直径达25min的(La0.7Ce0.3)(65)Al10Co25合金的全玻璃棒材。与单一稀土合金La65Al10Co25和Ce65Al10Co25的玻璃形成能力(GFA)相比，原子尺寸相近、价电子结构不同的La和Ce的共存明显改善了(LaxCe1-x)(65)Al10Co25 BMG的玻璃形成能力，这不能用原子尺寸失配和负混合热等传统的玻璃形成能力标准来解释。提出了一个热力学模型来评价这种替代效应，对相似原子共存引起的GFA的明显改善给予了合理的解释。(C)2007年Acta Materialia Inc.由爱思唯尔有限公司出版。保留所有权利。
The glass-formation range of bulk metallic glasses (BMGs) based on lanthanum and cerium was pinpointed in the La-Al-Co, Ce-Al Co and pseudo-ternary (La-Ce)-Al-Co systems, respectively, by copper mold casting. Through the stepwise substitution of La for solvent Cc in (LaxCe1-x)(65)Al10Co25 alloys (0 < x < 1), the fully glassy rods of the (La0.7Ce0.3)(65)Al10Co25 alloy can be successfully produced up to 25 min in diameter by tilt-pour casting. Compared with the glass-forming ability (GFA) of single-lanthanide-based alloys, La65Al10Co25 and Ce65Al10Co25, the coexistence of La and Ce with similar atomic size and various valence electronic structure obviously improves the GFA of (LaxCe1-x)(65)Al10Co25 BMGs, and this cannot be explained by the conventional GFA criteria for BMGs, e.g. atomic size mismatch and negative heats of mixing. A thermodynamic model was proposed to evaluate this substitution effect, which gives a reasonable explanation for the obvious improvement of GFA induced by the coexistence of similar atoms. (c) 2007 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.