Abstract The interfaces introduced in metals by heterostructural design play crucial roles in mechanical behaviors. Here the effect of gradient interfaces on mechanical behavior was investigated in a laminated Cu–30Zn sample composed of coarse-grained and ultrafine-grained layers. Tensile tests revealed a superior strength-ductility synergy with extraordinary strengthening and work hardening. By combining the measurements of height contour and strain distribution using digital image correlation, the development of strain gradient was detected in the near-interface zone during tension, which was caused by the mechanical incompatibilities across interfaces and the synergetic constraint between layers. The intensity of strain gradient in the near-interface zone increased with tensile strain, which was accommodated by the accumulation of geometrically necessary dislocations, thereby resulting in extra back stress and dislocation strengthening.

中文翻译：

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粗/超细晶粒层压板的额外强化：梯度界面的作用

摘要 通过异质结构设计在金属中引入的界面在机械行为中起着至关重要的作用。在这里，在由粗晶粒和超细晶粒层组成的层状 Cu-30Zn 样品中研究了梯度界面对力学行为的影响。拉伸试验显示出优异的强度-延展性协同作用，具有非凡的强化和加工硬化。通过使用数字图像相关性结合高度轮廓和应变分布的测量，在张力过程中在近界面区检测到应变梯度的发展，这是由界面之间的机械不相容性和层间的协同约束引起的。近界面区的应变梯度强度随着拉伸应变的增加而增加，