Li Shuang, Wang Wenyan, Cui Yunfeng, Xie Jingpei, Wang Aiqin, Mao Zhiping, Zhang Feiyang
School of Materials Science and Engineering, Henan University of Science and Technology, Luoyang 471023, China.
Digital Molding Engineering Research Center of Tungsten and Molybdenum Materials in Henan Province, Luoyang 471822, China.
Materials (Basel). 2025 Mar 26;18(7):1480. doi: 10.3390/ma18071480.
This study investigates how Zr doping influences the deformation behavior of Cu-Zr/AlCu/Al composites through molecular dynamics simulations. The impact of Zr content (ranging from 0 to 0.8 wt%) and strain rate on phase evolution, dislocation dynamics, and fracture mechanisms under vertical and horizontal tensile loading was examined. The results indicate that Zr doping achieves a balance between strength and plasticity by means of solute drag, amorphization, and phase competition. At a Zr concentration of 0.2 wt%, the formation of the body-centered cubic (BCC) phase reached a peak (22.04% at ε = 0.11), resulting in a maximum tensile strength of 9.369 GPa while maintaining plasticity due to limited face-centered cubic (FCC) decomposition. A moderate Zr content of 0.6 wt% maximizes strength through amorphization but significantly diminishes plasticity due to excessive FCC-to-BCC transitions. Higher Zr concentrations (0.8 wt%) lead to solute supersaturation, which suppresses phase transitions and slightly reduces toughness by causing hexagonal close-packed (HCP) phase accumulation. The strain rate markedly enhances both strength and plasticity in vertical loading by accelerating dislocation interactions. Vertical tensile deformation initiates brittle fracture, whereas horizontal loading results in ductile failure through sequential load transfer from AlCu layers to Al/Cu interfaces, ultimately causing interfacial decohesion. These findings underscore the essential roles of Zr content and strain rate in modulating phase transformations and interface responses. The research offers a framework for creating gradient Zr-doped or multi-scale composites with optimized strength, plasticity, and damage tolerance suitable for aerospace and electronics applications, where trace Zr additions can reinforce Cu matrices.
本研究通过分子动力学模拟研究了Zr掺杂如何影响Cu-Zr/AlCu/Al复合材料的变形行为。研究了Zr含量（范围为0至0.8 wt%）和应变速率对垂直和水平拉伸载荷下相演变、位错动力学及断裂机制的影响。结果表明，Zr掺杂通过溶质拖拽、非晶化和相竞争实现了强度与塑性之间的平衡。在Zr浓度为0.2 wt%时，体心立方（BCC）相的形成达到峰值（在ε = 0.11时为22.04%），从而产生了9.369 GPa的最大拉伸强度，同时由于有限的面心立方（FCC）分解而保持了塑性。中等Zr含量0.6 wt%通过非晶化使强度最大化，但由于FCC向BCC的过度转变而显著降低了塑性。较高的Zr浓度（0.8 wt%）导致溶质过饱和，抑制了相变，并通过引起六方密排（HCP）相堆积而略微降低了韧性。应变速率通过加速位错相互作用在垂直加载中显著提高了强度和塑性。垂直拉伸变形引发脆性断裂，而水平加载则通过从AlCu层到Al/Cu界面的顺序载荷转移导致韧性失效，最终引起界面脱粘。这些发现强调了Zr含量和应变速率在调节相变和界面响应中的重要作用。该研究为创建具有优化强度、塑性和损伤容限的梯度Zr掺杂或多尺度复合材料提供了一个框架，适用于航空航天和电子应用，其中微量Zr添加可以增强Cu基体。
