期刊
MICROSCOPY AND MICROANALYSIS
卷 28, 期 4, 页码 1359-1369出版社
CAMBRIDGE UNIV PRESS
DOI: 10.1017/S1431927621012988
关键词
CuNi alloys; interdiffusion; miscibility gap; thin films
The miscibility of CuNi alloys was investigated using APT, revealing a miscibility gap at 573 K and total mixing at higher temperatures. The critical temperature and Ni concentration of the miscibility gap were determined through experiments and modeling.
The unclear miscibility of CuNi alloys was investigated with atom probe tomography (APT). Multilayered thin film samples were prepared by ion beam sputtering (IBS) and focused ion beam (FIB) shaping. Long-term isothermal annealing treatments in a UHV furnace were conducted at temperatures of 573, 623, and 673 K to investigate the mixing process. The effective interdiffusion coefficient of the nanocrystalline microstructure (including defect diffusion) was determined to be D-eff = 1.86 x 10(10) m(2)/s x exp(-164 kJ/mol/RT) by fitting periodic composition profiles through a Fourier series. In nonequilibrium states, microstructural defects like grain boundaries and precipitates were observed. While at the two higher temperatures total mixing is observed, a clear experimental evidence is found for a miscibility gap at 573 K with the boundary concentrations of 26 and 66 at%. These two compositions are used in a subregular solution model to reconstruct the phase miscibility gap. So, the critical temperature T-C of the miscibility gap is found to be 608 K at a concentration of 45 at% Ni.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据