液体Ni-Cu中的化学短程订单
Dirk Holland-Moritz1, Fan Yang1, Thomas C Hansen2
1Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt, 51170 Köln, Germany.
概括
中子衍射揭示了液态-铜 (Ni-Cu) 合金中的化学短程秩序,表明非理想的溶液行为. 这一发现挑战了先前的假设,并表明了Ni-Cu的关键组成波动.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 经常假定Ni-Cu系统是形成理想的解决方案.
- 了解液体金属合金的行为对于各种工业应用至关重要.
研究的目的:
- 为了调查液体Ni-Cu合金中化学短程秩序的存在.
- 为了确定Ni-Cu是否表现出非理想溶液行为.
主要方法:
- 使用同位素替代与零散射器62Ni和63Cu的中子衍射.
- 对度-度结构因子的分析,S_CC(q).
主要成果:
- 在S_CC中的振荡提供了证据,证明液体Ni-Cu中的化学短程秩序.
- 观察到的行为表明非理想的溶液特性,与混合测量的自由度保持一致.
- 在低动量转移时S_CC(q) 的温度依赖性表明了关键的组成波动.
结论:
- 液体Ni-Cu合金显示化学短程顺序,与理想溶液行为假设相矛盾.
- 这些发现凸显了Ni-Cu化的复杂性质及其对组成波动的倾向.
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