Effect of amorphous layer parameters on tensile behavior of amorphous/crystalline CuZr/Cu composites

• Published in: Materials today communications 2024-12, Vol.41, p.110887, Article 110887
• Main Authors: Doan, Dinh-Quan, Chu, Van-Tuan, Tran, Anh-Son, Pham, Anh-Vu, Nguyen, Van-Thoai, Vu, Hong-Son, Hoang, Van-Han, Pham, The-Tan
• Format: Article
• Language: English
• Subjects: Amorphous shell; Amorphous/crystalline composite; Interface; MD simulation
• ISSN: 2352-4928; 2352-4928
• DOI: 10.1016/j.mtcomm.2024.110887

This study investigates the mechanical behavior and deformation property of CuZr/Cu amorphous/crystalline (AC) composites subjected to uniaxial tensile loading. The results reveal significant insights by varying amorphous shell thickness and amorphous alloy composition. Reducing the amorphous shell thickness from 20 Å to 5 Å increases the tensile strength of the composite from 2.715 GPa to 4.668 GPa due to the enhanced AC interface effect. The insertion of crystalline phases in the amorphous matrix induces nucleation zones for the shear bands and dislocations, affecting the plastic flow distribution. The shear strain and residual stress predominantly manifest in the amorphous shell. A thinner amorphous shell induces substantial shear strain in crystalline phases, promoting homogeneous deformation. The dislocations prompt plastic deformation in crystalline phases, altering atomic configurations. The AC interfaces initiate deformation nucleation, generating partial dislocations, stacking faults, and twinning in the tension. Besides, the total dislocation length rises with strain increase and thinner amorphous shell. Moreover, the increase of Cu content in the amorphous CuZr shell leads to increased tensile strength and elastic modulus. The higher Cu content increases the concentration of shear strain regions in the composites. The deformation mechanism is also switched from the dominant shear band to the homogenous deformation with increasing Cu content in the amorphous shell. Finally, the phase change shows that the FCC phase decreases and the amorphous phase gain is less as the percentage of Cu in the amorphous increases. [Display omitted] ●Studying CuZr/Cu AC composites with changes in shell thickness and alloy composition of amorphous reveals insights.●Thinner amorphous shell enhances tensile strength and elastic modulus due to AC interface effects.●The AC interface is the zone of nucleation of shear bands and dislocations, affecting plastic flow.●Thinner amorphous shell promotes deformation in crystalline phases.●The increased Cu content boosts tensile strength and switches the deformation mechanism from shear band to homogeneous.