Density functional theory investigation on the stability, adhesion strength, tensile properties and fracture behavior of γ-Fe/Cu heterogeneous nucleation interface
Density functional theory investigation on the stability, adhesion strength, tensile properties and fracture behavior of γ-Fe/Cu heterogeneous nucleation interface
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DOI：
10.1016/j.rinp.2021.104143
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发表时间：
2021-04-18
影响因子：
5.3
通讯作者：
Fu, Yi-Zheng
中科院分区：
文献类型：
--
作者：
Wang, Ming-Jie;Zhang, Guo-Wei;Fu, Yi-Zheng
为了从理论上研究钢/铜双金属中γ-Fe/Cu界面的稳定性和非均匀形核特性，用密度泛函理论研究了6种表面模型和7种界面模型。用第一性原理计算了三种典型的Fe/Cu界面模型的界面稳定性、结合能、电子性质、拉伸过程和断裂行为。同时，揭示了纯铁在铜基合金上异质形核的机理。结果表明，当层数分别为9层和7层时，三种Fe/Cu界面的Bramfitt晶格失配率均为4.11%，且所有的铜表面和铁表面都有收敛的趋势。在三种具有HCP结构的Fe/Cu界面中，Fe(110)/Cu(110)界面具有较高的金属键强度和稳定的离子性质。当应变为37%时，拉伸应力的最大值约为20.3 Gpa，Fe和Cu原子之间的电子密度下降到消失。计算出具有HCP结构的Fe(110)/Fe(110)界面的粘附功为1.88J/m(2)，高于铜/铜熔体之间的粘附功(1.78J/m(2))，证明了Fe颗粒促进了铜原子的异质形核，从而解释了铜基合金的细化作用。
To theoretically study the stability and the heterogeneous nucleation characteristics of gamma-Fe/Cu interface in steel/ copper bimetallic, the six surface models and seven interface models were investigated through density functional theory. Besides, the interface stability, adhesion energy, electronic properties, tensile process and fracture behavior of three kinds typical Fe/Cu interface model were calculated by first-principles calculations. Simultaneously, the mechanism on heterogeneous nucleation of pure Fe on Cu-based alloy was revealed. The results indicate that the bramfitt's lattice mismatches of all the three Fe/Cu interfaces were both 4.11%, and all the Cu surfaces and the Fe surfaces were trends to converge, when the number of layers were 9 and 7, respectively. Among three kinds Fe/Cu interfaces with HCP structure, the Fe (1 1 0)/Cu (110) interface shown higher strength of metallic bonds and stable ionic properties. When the strain is 37%, the maximum value of the tensile stress is about 20.3GPa and the electron density between Fe and Cu atoms drop to disappear. The calculated adhesion work of Fe (11 0)/Cu (110) interface with HCP structure is 1.88 J/m(2), is higher than that between Cu/Cu melt (1.78 J/m(2)), which proved that the Fe particles can promote heterogeneous nucleation of Cu atoms and then account for the grain refinement of Cu-based alloy.