Hot Compression Deformation and Activation Energy of Nanohybrid-Reinforced AZ80 Magnesium Matrix Composite

Abstract

The hot deformation test of the nano silicon carbide (nano-SiC) and carbon nano tubes (CNT) hybrid-reinforced AZ80 matrix composite was performed at compression temperatures of 300–450 °C and strain rates of 0.0001–1 s−1. It could be observed that the flow stress of the nanocomposite rose with the reduction of deformation temperature and the increase of strain rate. The hot deformation behaviors of the composite could be described by the sine-hyperbolic Arrhenius equation, and deformation activation energy (Q) was calculated to be 157.8 kJ/mol. The Q values of the extruded nanohybrid/AZ80 composite in this study and other similar studies on extruded AZ80 alloys were compared in order to analyze the effect of the addition of reinforcement, and the effects of deformation conditions on activation energy were analyzed. Finally, the compression microstructure in an unstable condition was carefully analyzed, and results indicated that the phenomenon of local instability was easy to occur at the compression specimen of the nanohybrid/AZ80 composite under deformation conditions of low temperature with high strain rate (300 °C, 0.1–0.01 s−1), and high temperature with low strain rate (450 °C, 0.0001 s−1).

Hot deformation behavior and processing map development of Mg/Al2O3 composite: A case study of extrusion ratio effects

“…This behavior can be attributed to: (1) Smaller grain size with more grain boundaries after the 20:1 extrusion ratio since the slide of grain boundary is easier in the materials with fine-grained microstructure during the hot compression process, thus reducing the activation energy value, and (2) Twinning, known as a barrier for moving dislocation, thus increasing the value of Q of the composite extruded at a lower extrusion ratio that contains more twins than the fine-grain composite. [62][63][64] Zener-Hollomon parameter. In order to evaluate the correlation between Z and σ, ln Z was drawn versus ln(sinh(as)) for the first and second extrusion passes of Mg/Al 2 O 3 are shown in Figure 9(a) and (b).…”

Graphene Family Nanomaterial Reinforced Magnesium-Based Matrix Composites for Biomedical Application: A Comprehensive Review

“…The immobilization of CNT and Gr in metallic biomaterials prevents the exposure of adjacent tissues, therefore providing biosafety for these kinds of particles [47]. It is worth noting that the application of biodegradable Mg-GFN composites fabricated through various fabrication procedures and structural modifications for load-bearing implant process for bone substitution and reproduction attracts a huge amount of attention [166][167][168][169][170][171][172][173][174][175][176][177][178][179][180]. Taking into consideration the outstanding biological response and incredible mechanical characteristics of Gr, as described in earlier sections, it is anticipated that a number of implants and scaffolds will be created in the near future.…”