Transition from shear to stress-assisted diffusion of copper–chromium nanolayered thin films at elevated temperatures
Transition from shear to stress-assisted diffusion of copper–chromium nanolayered thin films at elevated temperatures
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铜铬纳米层薄膜在高温下从剪切到应力辅助扩散的转变
DOI：
10.1016/j.actamat.2015.08.016
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发表时间：
2015
期刊：
影响因子：
9.4
通讯作者：
G. Dehm
中科院分区：
文献类型：
--
作者：
R. Raghavan;J. Wheeler;T. Harzer;V. Chawla;Soundès Djaziri;K. Thomas;B. Philippi;C. Kirchlechner;B. N. Jaya;J. Wehrs;J. Michler;G. Dehm
研究了Cu-Cr纳米膜和名义成分为Cu20Cr80at的合金膜的力学行为。%在25 ~ 300℃的温度下进行微压缩试验。与纳米层膜相比，膜层厚度越小，应力水平越高，塑性变形和破坏就越明显。纳米层薄膜的塑性始于较软的Cu层，随后在应力-应变曲线上出现有限应变硬化响应。在25°C和100°C时，纳米层膜在Cr柱状边界处由于剪切和撕裂而出现峰值强度后的应变软化响应。在200°C和300°C的高温下，Cu - cr界面发生了由剪切和裂纹形成的转变，导致纳米晶Cu层的异常晶粒生长或珠化。另一方面，Cu20Cr80at。合金薄膜在高温下均表现为柱状屈曲破坏，但在室温下，薄膜中强度最高的屈曲促进了剪切。
The mechanical behavior of Cu–Cr nanolayered films and an alloy film of nominal composition Cu20Cr80at.% was studied by microcompression testing at temperatures from 25 °C to 300 °C. Comparing nanolayered films, plastic deformation and failure occurred at consistently higher stress levels in the film with the smaller layer thicknesses. Plasticity in the nanolayered films always initiated in the softer Cu layers followed by a finite strain-hardening response in the stress–strain curves. Failure indicated by a strain-softening response following the higher peak strength due to shearing and tearing at columnar boundaries of Cr was observed in the nanolayered films at 25 °C and 100 °C. A transition from shearing and crack formation across the Cu–Cr interfaces leading to anomalous grain growth or beading of the nanocrystalline Cu layers was observed at elevated temperatures of 200 °C and 300 °C. On the other hand, the Cu20Cr80at.% alloy film exhibited failure by columnar buckling consistently at elevated temperatures, but shearing promoted by buckling at the highest strengths among the films at ambient temperature.
影响因子：
9.4
作者：
Knorr, I.;Cordero, N. M.;Volkert, C. A.
通讯作者：
Volkert, C. A.