Exploring the Influence of the Coarse Grain Size and Ag Atomic Content on Mechanical Properties of Bimodal Nanotwinned Cu-Ag Alloys

• Published in: JOM (1989) 2023-07, Vol.75 (7), p.2763-2770
• Main Authors: Zhi, Youran, Guo, Ao, Zhang, Feng, Tang, Qiaoyun, Yang, Huan
• Format: Article
• Language: English
• Subjects: Alloys; Atom concentration; Chemistry/Food Science; Copper; Copper base alloys; Deformation; Deformation mechanisms; Ductility; Earth Sciences; Engineering; Environment; Experiments; Grain boundaries; Grain Boundary Segregation; Grain size; Mechanical properties; Metals; Molecular dynamics; Physics; Segregation; Silver; Simulation; Strain analysis; Technical Article; Tensile tests; Ultrafines; Yield stress
• ISSN: 1047-4838; 1543-1851
• DOI: 10.1007/s11837-023-05810-w

The deformation mechanism of bimodal nanotwinned (NT) Cu-Ag alloy with grain boundary segregation has been simulated by the molecular dynamics method. The equidistance scaling method has been used to generate a grain boundary affect zone. Construction of a bimodal NT Cu-Ag alloy model was achieved by implanting coarse NT grains in an ultrafine grain matrix. Uniaxial tensile experiments were carried out on NT Cu-Ag alloys to explore the deformation mechanism of Cu-Ag alloys in different strain conditions. By analyzing atomic stress–strain images obtained by uniaxial tensile testing, the strength of the bimodal NT Cu-Ag alloy models has been discovered to have a relationship with the coarse grain size and Ag atom concentration. A detailed description is given based on the dislocation activity and the associated deformation mechanism. The properties of the bimodal NT Cu-Ag alloys have been analyzed by surveying the intrinsic dislocation activity of the models.