A modified maxwell-pulse thermoplastic constitutive model of in-situ Ta-particle reinforced Zr-based bulk metallic glass composites

• Published in: Progress in natural science 2024-08, Vol.34 (4), p.753-766
• Main Authors: Gong, Pan, Wang, Zhuang, Yu, Guoqing, Li, Maojun, Zhuo, Xin, Tang, Xuefeng, Zhang, Mao, Deng, Lei, Jin, Junsong, Churakova, A.A., Wang, Xinyun
• Format: Article
• Language: English
• Subjects: Bulk metallic glass composites; Constitutive model; Influence mechanism; Supercooled liquid region; Thermoplastic deformation
• ISSN: 1002-0071
• DOI: 10.1016/j.pnsc.2024.07.004

The impact of different Ta contents on the mechanical properties and thermoplastic forming ability of in-situ Ta-particle reinforced Zr–Cu–Al–Ni bulk metallic glass composites was studied. The composition (Zr55Cu30Al10Ni5)94Ta6 with the best comprehensive performance was chose for a systematic investigation into its thermoplastic behavior in the supercooled liquid region (SLR), with quantitative analysis conducted by the strain rate sensitivity index and activation volume. The steady-state flow stress and the stress overshoot intensity were augmented with deformation temperature decreasing, strain rate increasing, and the addition of the secondary phase, leading to a transition from Newtonian to non-Newtonian flow regime. The addition of the secondary phase deteriorated the rheological properties of the material. To solve the problem that the Maxwell-Pulse constitutive model showed an inability to accurately describe the steady-state flow process. A modified constitutive relationship, introducing the effect of the volume fraction of Ta particles on viscosity and elastic modulus in the steady-state flow process which was ignored in Maxwell-pulse model, was established. The fitting results of the true stress-strain curves of the modified Maxwell-pulse constitutive model were in better agreement with the experimental date than those of the Maxwell-pulse constitutive model, with higher prediction accuracy. The modified constitutive model well predicted the thermoplastic deformation behavior of (Zr55Cu30Al10Ni5)94Ta6. The influence mechanism of Ta particles on the flow behavior was explained that Ta particles increased the viscosity of amorphous matrix, thereby hindering its flow and ultimately leading to an increase in flow stress. •The best performance combination composition was selected from different Ta contents reinforced Zr-based BMGCs.•The m and Vact were employed to quantitatively evaluate the rheological behavior of BMGCs.•The modified Maxwell-Pulse constitutive model provided well prediction of the thermoplastic deformation behavior.•The weak stress area strongly induced the sluggish viscous flow of the amorphous matrix.