High Volume Fraction Research Articles

Deciphering the Stability of Porous Ionic Liquids: Flow Dynamics, Liquid Structure and Suspension Energetics.

The rheological behavior of porous ionic liquids comprising ZIF-8 suspensions in two Newtonian ionic liquids - trihexyltetradecylphos- phonium bis(trifluoromethylsulfonyl)imide and tri- hexyltetradecylphosphonium chloride - exhibited distinct and unexpected differences. ZIF-8 suspensions in the bis(trifluoromethylsulfonyl)imide-based liquid showed Bingham behavior with a measurable yield stress, whereas those in the chloride-based liquid remained Newtonian, even at high solid volume fractions of up to 17.4%. Remarkably, the viscosities of these porous liquids were not significantly higher than those of the pure ionic liquids. While explaining these behaviours, we could elucidate how the stability and dynamic properties of porous ionic liquids are governed by the highly structured liquid phases, determined experimentally and using molecular dynamics simulations, and by the balance between particle-particle and ZIF-8-ionic liquid inter- actions, as evidenced by the heat effects measured during particle dispersion.

Reversibly thermosecreting and convertible lubricative oil-in-water mixtures using multiple hydrogen bonding interactions

Achieving homogeneous oil and water mixing requires thorough droplet dispersions of both liquids. An additional component, such as a surfactant, particle, solvent or ion is normally required to stabilize the small liquid droplets by providing sufficiently low interfacial tensions or strong repulsive forces. Here we show that very stable oil-in-water mixtures can be created even at very high oil volume fractions by building multiple, high-strength hydrogen bonding interactions between water and a biocompatible and biodegradable oil trimethylolpropane trioleate, which make the oil molecules at the contact interface behave as pseudo-surfactants with ultrahigh interfacial activity. The resultant oil microdroplets can be reversibly thermosecreted from the continuous aqueous phase and lead to controllable formation/dissociation and switchable lubrication of the binary liquid mixture owing to the inherent thermal responsiveness of the intermolecular hydrogen bonding. Interestingly, although water is uncovered to possess a relatively poor lubricity, the liquid mixture yields an optimized lubrication that is even exceedingly comparable to pure oil at a water volume fraction as high as 80%.

Multi-scale finite element analysis of the strengthening and damage behavior of carbides with different characteristics in nickel-based superalloys

This study proposes a novel multi-scale numerical approach to explore the mechanical behavior and damage evolution in nickel (Ni)-based superalloys containing various carbide particles. At the nanoscale, the elastic properties of two distinct carbides are determined using first-principles calculations. At the microscale, finite element simulations (FEM) in ABAQUS are used to analyze the stress–strain relationship and local stress distribution within a three-dimensional representative volume element, as well as damage and fracture behavior. The model integrates the elastic–plastic response of the Ni matrix, the elastic-brittle fracture of micro-scale carbides, and the interface behavior between carbide and matrix. FEM findings are consistent with tensile test data, indicating that skeletal carbide promotes plasticity while blocky carbide elevates strength. The interface between blocky carbide and matrix is susceptible to cracking. When the carbide is oriented at 45° to the load direction, offering a balance of strength and plasticity. Stress concentration is reduced when carbides are uniformly distributed and present in high-volume fractions. The numerical method is well-suited for a thorough analysis of the comprehensive behavior of reinforced phase/metal-matrix composites.

The influence of diamine structure on low dielectric constant and comprehensive properties of fluorinated polyimide films

Three kinds of polyimide (PI) films with low dielectric constant and excellent comprehensive properties were prepared by polycondensation reaction employing 6FDA as the dianhydride monomer and 6FODA, TFMB and 6FDAM as the diamine monomers, respectively. The effects of diamine moieties on the low dielectric constant and comprehensive properties were investigated by experiments and theoretical simulations. All three PI films show excellent high temperature resistance. For instance, the 5 % weight loss temperature ranges from 495 to 511 °C, and the Tg from 305.5 to 347.2 °C. 6FDA/6FODA exhibits a higher dielectric constant (k) compared with the other two PIs because of low free volume fraction and low rotating energy barrier of torsion angle for 6FODA moieties. 6FDA/TFMB exhibits ultra-low k (1.84 at 104 Hz) being benefit from its high free volume fraction caused by the strong rigidity of molecular chain. Despite having the highest free volume fraction among the three PIs, 6FDA/6FDAM exhibits a slightly higher dielectric constant than 6FDA/TMFB due to the fact that the torsion angle for 6FDAM moieties has low rotating energy barrier, which is beneficial for improving the molecular polarizability. Meanwhile, all the PI films show excellent transparency in the visible light range as well as excellent mechanical properties. The results indicate that the microstructure of PI can be effectively adjusted, thus achieving an ultra-low k and excellent comprehensive properties by rationally designed diamine moiety.

Particle Sedimentation in a Fluid at Low Reynolds Number: A Generalization of Hindered Settling Described by a Two‐Phase Continuum Model

AbstractParticle‐fluid separation by settling is a ubiquitous process in Earth and Planetary Sciences. The settling velocity of particles is controlled by a balance between buoyancy and drag forces. Since the seminal work of George Gabriel Stokes, parameterizations for the reduction of particle velocities caused by viscous dissipation due to mutual interactions have been described by a non‐linear mapping between particle volume fraction and separation velocity. We argue that these parameterizations neglect important physical behavior at high particle volume fractions (>80% of the maximum packing) and are only appropriate when considering suspensions where the particle volume fraction does not evolve in space or time. We introduce a more general model that accounts for the energy dissipation caused by changes in local particle volume fraction, which introduces a new term similar to the compaction term at higher particle volume fraction. This term depends on a consolidation/compaction viscosity that measures the resistance to changes in solid volume fraction. We derive closure equations for this compaction viscosity under dilute and concentrated particle volume fraction limits. Numerical simulations show that the extended hindered settling model predicts two significant differences compared to traditional hindered settling. First, while the steepening of particle volume fraction fronts remains, a dynamic instability is also generated at the front. Second, the rate of growth and structure of a cumulate layer growing above a no‐flux boundary is affected by the compaction‐like term and predicts the trapping of a higher volume fraction of interstitial melt in a correspondingly thicker cumulate layer.

Mechanical force modeling and experimental verification of ultrasonic vibration assisted milling of high volume fraction SiCp/AL

Mechanical force modeling and experimental verification of ultrasonic vibration assisted milling of high volume fraction SiCp/AL

A new SLM-manufactured Al[sbnd]Si alloy with excellent room and elevated-temperature mechanical properties

The synergistic strengthening of multiple phases has long been an effective method of enhancing conventional metallic structural materials. However, the assembly of solute atoms with high solubility and low diffusion rate into highly stable and high-volume fraction nano-precipitates using the selective laser melting (SLM) technique is challenging. In this study, a new Al-9.0Si-2.8Fe-2.1Mn-1.1Ni (in wt%) alloy was fabricated using the SLM. The melt pool structure of the alloy exhibits equiaxed grain characteristics under optimum parameters, with large volume fractions of in-situ precipitated IMC-Al15(Fe,Mn,Ni)3Si2 and Si phases within the grains. The alloy demonstrates commendable tensile properties at room temperature (YS 373 ± 8 MPa, UTS 602 ± 12 MPa, El 4.2 ± 0.5 %) and retains excellent strength and ductility as well as creep resistance at elevated temperatures of 400 °C (YS 92 ± 3 MPa, UTS 100 ± 5 MPa, El 24 ± 0.7 %, steady-state creep rate ~ 10−5 s−1 under 60 MPa). Lamellar nano-Si phases can induce strain delocalization effects and grain boundary relaxation through partial dislocation twinning behavior, thereby coordinating high-temperature deformation. Under large deformations and prolonged creep processes, the transmission of external loads and the evolution of defects (The edge dislocation at interfaces, the stacking faults and deformation twins within the Si phase) effectively transfer stress to low-load-bearing regions, promoting the delocalization of deformation. The abundant second phases within the alloy (IMC and Si phases) hinder dislocation movement and promote dislocation multiplication, maintaining ultra-high deformation resistance and low steady-state creep rate. Due to the absence of heat treatment and the addition of expensive elements, the alloy has wide industrial application potential.

Growth of MoS2 Nanosheets on Brush-Shaped PI-ZnO Hybrid Nanofibers and Study of the Photocatalytic Performance.

The design and preparation of advanced hybrid nanofibers with controllable microstructures will be interesting because of their potential high-efficiency applications in the environmental and energy domains. In this paper, a simple and efficient strategy was developed for preparing hybrid nanofibers of zinc oxide-molybdenum disulfide (ZnO-MoS2) grown on polyimide (PI) nanofibers by combining electrospinning, a high-pressure hydrothermal process, and in situ growth. Unlike simple composite nanoparticles, the structure is shown in PI-ZnO to be like the skeleton of a tree for the growth of MoS2 "leaves" as macro-materials with controlled microstructures. The surface morphology, structure, composition, and photocatalytic properties of these structures were characterized using scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and UV-vis spectroscopy. The ultra high-volume fraction of MoS2 can be grown on the brush-shaped PI-ZnO. Decorating ZnO with nanosheets of MoS2 (a transition metal dichalcogenide with a relatively narrow band gap) is a promising way to increase the photocatalytic activity of ZnO. The hybrid nanofibers exhibited high photocatalytic properties, which decomposed about 92% of the methylene blue in 90 min under visible light irradiation. The combination of MoS2 and ZnO with more abundant surface-active sites significantly increases the spectral absorption range, promotes the separation and migration of carriers, and improves the photocatalytic characteristics.

Impact of sintering temperature and KMnO4 addition on the growth of Bi2212 ceramics

In this study, the highest volume fraction was obtained by the combined effect of KMnO4 doping and different sintering temperatures (840 and 850 °C). Bi2Sr2CaCu2(KMnO4)xO8+δ compounds with x = 0, 0.01, 0.03, 0.05 and 0.07 were prepared by the conventional solid-state reaction method. The phase composition and microstructure were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and Raman Spectroscopy. The XRD phase study showed that the optimum sintering temperature was 850 °C with a KMnO4 doping concentration of 0.05. With increased doping (x), the texture of Bi2212 became more crystalline, with a grain growth preference along the (00l) direction. It is clear that the rate of formation of the Bi2212 phase is favored by high sintering temperature and addition of KMnO4. The line intensities of the Bi-2212 phase were found to increase significantly with KMnO4 addition up to the critical value of x = 0.01 and the cell structure volume is seen to decrease with increasing doping rate. This may be attributed to inhomogeneities in oxygen concentration This indicates that the sintering temperature has a strong influence on the structural and morphological properties. As reported in the literature, the Raman modes at 489.76 cm-1 and 630 cm-1 are associated with the vibrations of O(3)BiA1g and O(2)SrA1g along the c axis for the Bi-2212 phase. The A1g modes are symmetric for vibrations of Bi, Sr, Ca, Cu, OBi, OSr and OCu along the c axis.

Tuning the Microstructure and Mechanical Properties of Al-Co-Cr-Fe-Ni-Ti Compositionally Complex Alloys Manufactured by Means of L-DED

Abstract In the current study, a combinatorial high-throughput screening approach based on CALPHAD simulations and experimental validation has been utilized to explore a Co2CrFeNi2-Al-Ti CCA-system. This technique, introduced by Kaspar et al. (High Entropy Alloys Mater. https://doi.org/10.1007/s44210-023-00023-x), allows to perform an accelerated alloy development within a wide compositional range and automated fabrication of graded components with varying chemical composition and microstructure. Extended by semi-automated analytical characterization of the produced samples, this approach enables to design novel compositionally complex alloys (CCAs) with promising properties for specific requirements. In our current work, a multiphase design of L12 γ′-strengthened Co2CrFeNi2-Al-Ti CCAs partially tolerating the disordered BCC-A2 or ordered B2 phases in the alloy microstructure has been utilized. The samples with three different chemical compositions were manufactured by means of laser directed energy deposition (L-DED). By subsequent two-step heat treatment, different phase compositions and microstructures have been realized with a main objective to achieve a high volume fraction of L12 γ′ precipitations. Mechanical properties of investigated alloys were characterized by means of tensile tests. Depending on chemical and phase composition of the alloys, the ultimate tensile strength varied in the range of 1060-1150 MPa. The formation of BCC-B2 phase led to decreased yield to tensile strength and showed a detrimental effect on ductility of investigated alloys.

Effect of Laser Quenching on Wire-Powder Collaborative Arc Additive Manufacturing of Ti6Al4V-Cu Alloys with 2.4% and 7.9% Copper Content.

In this work, Ti6Al4V-Cu alloys with different Cu contents (2.4 and 7.9 wt.%) were fabricated using novel wire-powder synchronous arc additive manufacturing to analyze the effect of laser quenching on Ti6Al4V-Cu alloys. The results show that this method can successfully produce Ti6Al4V-Cu alloys with a uniform composition. As the copper content increased, the alloy transitioned from a Widmanstätten structure to a basketweave structure, and the yield strength and tensile strength of the alloy increased by approximately 35% due to grain refinement and the high volume fraction of Ti2Cu with eutectic lamellae. The microhardness of the alloys significantly increased after laser quenching, particularly for those with low copper contents (from 311 HV to 510 HV). Laser quenching also enhanced the corrosion resistance of the alloy in a 3.5% NaCl solution.

The Influence of Resin Volume Fraction on Selected Properties of Polymer Concrete.

Polymer concrete is a promising material with applications in construction and architecture; however, guidelines for its design and optimization are not well-established in the literature. This study aimed to evaluate how resin volume fraction and aggregate size distribution affect key properties of polyester polymer concrete, including flexural strength, compressive strength, water absorption, and material cost. Three types of quartz aggregates with different particle size distributions were used, as follows: small (below 0.5 mm, quartz dust), medium (0.2-2.0 mm, quartz sand), and large (2.0-10.0 mm, quartz gravel). The resin volume content varied from 5% to 30%. Differences in apparent density, open porosity, water absorption, flexural strength, compressive strength, and material cost were analyzed as functions of resin volume content and aggregate size. The results showed that apparent density and mechanical properties are positively correlated with resin content for small and medium aggregates; however, in the case of large aggregates, flexural strength decreased when the resin volume content exceeded 20%. A significant reduction in material porosity and water absorption (to ~0.4% and ~0.2%, respectively) was observed at high resin volume fractions.

Trabecular Bone Ontogeny of the Human Distal Tibia.

There is an increasing understanding of how trabecular bone adapts to biomechanical changes during ontogeny. However, limited research exists regarding the distal tibia, which is important in weight-bearing locomotion as part of the ankle joint. This study aims to document the ontogenetic trabecular patterns of the distal tibia, in addition to changes in its structural heterogeneity. Thirty-eight distal tibiae, ranging in age from 28 intrauterine weeks to 8 postnatal years, from the Scheuer juvenile skeletal collection were examined. Trabecular bone was analyzed using a quantitative volume of interest approach and qualitative whole bone mapping following microcomputed tomography. Fetal and perinatal tibia lack mature organization and are associated with high bone volume fraction. During the first year of life, there is a decrease in bone volume fraction and an indication of early re-organization of trabecular struts in the distal tibia. After one year of age, the distal tibia exhibits increased trabecular structural heterogeneity. The trabecular architecture of the fetal and perinatal distal tibia lacks mature organization and instead reflects ossification patterns. At these stages, there is a rapid accumulation of bone mass associated with gestational overproduction, hypothesized to be in preparation for subsequent postnatal changes. During the first year of life there is a decrease in volume fraction, associated with constructive regression. It is postulated this is related to changing biomechanical forces associated with the bipedal gait, in addition to growth demands. After one year of age, the distal tibia exhibits structural heterogeneity with trabecular adaption to accommodate specific bipedal stresses.

A Complex Concentrated Alloy with Record-High Strength-Toughness at 77 K.

High strength and large ductility, leading to a high material toughness (area under the stress-strain curve), are desirable for alloys used in cryogenic applications. Assisted by domain-knowledge-informed machine learning, here a complex concentrated Fe35Co29Ni24Al10Ta2 alloy is designed, which uses L12 coherent nanoprecipitates in a high volume fraction (≈65 ± 3 vol.%) in a face-centered-cubic (FCC) solid solution matrix that undergoes FCC-to-body-centered-cubic (BCC) phase transformation upon tensile straining. Unlike FCC-to-BCT phase transformation involving brittle carbon-enriched martensite, the BCC martensite in this alloy does not cause brittleness at 77 K. The Fe35Co29Ni24Al10Ta2 multi-principal element alloy achieves a high yield strength ≈1.4GPa, a high work hardening rate >4GPa, an ultimate tensile strength ≈2.25GPa, and a large uniform elongation ≈45%, leading to record-high material toughness compared with previous cryogenic alloys such as 316L series stainless steels and recent high-entropy alloys. The nanoprecipitates with nanoscale spacing (≈7.5nm), apart from serving as dislocation obstacles for strengthening and dislocation sources for sustainable ductility, also undergo deformation twinning. Taken together, these mechanisms are found to be highly effective in strengthening and strain hardening upon tensile straining at liquid nitrogen temperature. These findings demonstrate how to effectively integrate strengthening mechanisms to synergize superior mechanical properties in special-purpose alloys.

Effect of MnO2 addition on the microstructure and properties of high-volume fraction SiCp/Al composites fabricated by pressureless melt infiltration

High-volume fraction silicon carbide particles reinforced aluminum matrix composites (SiCp/Al) with low coefficient of thermal expansion (CTE) and high thermal conductivity (TC) were fabricated by infiltrating Al-Si-Mg alloy in air atmosphere without pressure into porous SiC preforms doped with different manganese dioxide (MnO2) content in order to investigate the effectiveness of MnO2 as infiltration aid. The effect of MnO2 on the infiltration time, microstructure and thermo-mechanical properties of the composite materials were studied. The volume ratio of SiC to MnO2 was set at 100:0, 100:5, 100:10 & 100:15 respectively. Obtained results showed the effectiveness of MnO2 as infiltration aid as the infiltration time was significantly reduced, the wetting between SiC and Al and interfacial bonding strength were considerably improved with the addition of MnO2. Harmful and brittle aluminum carbide (Al4C3) was not detected at the interface of the Al alloy and SiC ceramic phase. The composites with 100:15 MnO2 and 100:10 MnO2 content were found to have less incubation period and infiltration time. Optimum dispersion of SiC particles in the Al alloy and better properties were obtained with 100:10 MnO2 content composite samples. The properties are; a coefficient of thermal expansion (RT to 473 K) of 9.3 × 10−6 K−1, a thermal conductivity of 200.5 W/(mK), a hardness of 145.2 HBW and a bending strength of 338.0 MPa.

Prolate spheroids settling in a quiescent fluid: clustering, microstructures and collisions

In this study we investigate the sedimentation of prolate spheroids in a quiescent fluid by means of the particle-resolved direct numerical simulation. With the increase of the particle volume fraction $\phi$ from $0.1\,\%$ to $10\,\%$ , we observe a non-monotonic variation of the mean settling velocity of particles, $\langle V_s \rangle$ . By virtue of the Voronoi analysis, we find that the degree of particle clustering is highest when $\langle V_s \rangle$ reaches the local maximum at $\phi =1\,\%$ . Under the swarm effect, clustered particles are found to preferentially sample downward fluid flows in the wake regions, leading to the enhancement of the settling speed. As for lower or higher volume fractions, the tendency of particle clustering and the preferential sampling of downward flows are attenuated. The hindrance effect becomes predominant when the volume fraction exceeds 5 % and reduces $\langle V_s \rangle$ to less than the isolated settling velocity. Particle orientation plays a minor role in the mean settling velocity, although individual prolate particles still tend to settle faster in suspensions when they deviate more from the broad-side-on alignment. Moreover, we also demonstrate that particles are prone to form column-like microstructures in dilute suspensions under the effect of wake-induced hydrodynamic attractions. The radial distribution function is higher at a lower volume fraction. As a result, the collision rate scaled by the particle number density decreases with the increasing volume fraction. By contrast, as another contribution to the particle collision rate, the relative radial velocity for nearby particles shows a minor degree of variation due to the lubrication effect.

Deformation of a macroscopic yield stress hydrogel during the free fall of a sphere

We investigate the deformation of a macroscopic yield stress fluid consisting of a mixture of water and hydrogel (superabsorbent polymer) with high solid volume fractions and different grain size distributions during the settling of a sphere. The fluid's rheology combines viscous, elastic, and plastic behaviors and is described by a shear-thinning yield stress model. Experiments were conducted in two motion regimes: the continuous fall, where the sphere reaches a constant terminal velocity, and the intermittent regime, with alternating periods of motion and no-motion. Particle image velocimetry and spatiotemporal images of laser-illuminated fluid cross sections were used to determine the yield surface and analyze local grain motion dynamics. In both regimes, a yield surface similar to an ovoid spheroid is observed. A scaling law is derived for lateral deformation (perpendicular to the fall direction), dependent on sphere size and Yield number (Y). This scaling law provides reliable estimations of maximum deformation widths, consistent with experiments in the literature using different yield stress fluids. For all fluid samples used, the flow within the yielded region shows a strong fore-aft asymmetry, characterized by a negative wake at the back of the sphere related to the elastic component of the bulk deformation. In the intermittent motion regime, we find that the transition from no-motion to motion is associated with reaching a maximum level of compression or triggering sufficient irreversible plastic events in the region of fluid under compression. This leads to a sudden avalanche-type of event where stresses are relaxed and the sphere starts moving downward again.

Particle dynamics at fluid interface by pseudo-potential lattice Boltzmann method coupled with smoothed profile method

Fluid–solid coupling widely exists in some natural phenomena and industrial applications. However, it is still an important challenge to correctly capture the transient changes of particles at fluid interface. We develop a lattice Boltzmann model for particle dynamics at fluid interface, which adopts a coupling strategy by combining the pseudo-force (Shan-Chen) multiphase multicomponent model and the smoothed profile method. In the coupling strategy, a novel extrapolation boundary condition is applied for fluid–solid interface, a repulsive force (bounce-back force) between solid node and fluid node is introduced in the coexistence region (at the fluid–solid interface), to form the interaction between fluid and solid particle. Thanks to the proposed fluid–solid coupling method, the drag force on solid particles can be correctly described, especially for situations of high solid volume fractions. It is found that the wetting angle θ between fluid interface and particle surface is basically linear with the repulsive force coefficient difference ΔG. What is more, to further validate the reliability of our proposed model, we performed two groups of simulations for different Bos = 0.51 (0.84) and 0.83 (1.35), they are the single particle trapped under gravity at deformed fluid interface and the falling single particle impacts fluid interface in the presence of gravity, respectively, and good agreements between simulation results and experimental ones in the description of the relationship between the inertial force and the interfacial tension are obtained, and their correlations are both close to 1, which proves the reliability of our proposed model.

Jet Interaction with Galaxy Cluster Mergers

Active galactic nucleus (AGN) bubbles in cool-core galaxy clusters are believed to facilitate the transport of cosmic-ray electrons (CRe) throughout the cluster. Recent radio observations reveal the complex morphologies of cluster diffuse emission, potentially linked to interactions between AGN bursts and the cluster environment. We perform 3D magnetohydrodynamical simulations of binary cluster mergers and inject a bidirectional jet at the center of the main cluster. Kinetic, thermal, magnetic, and cosmic ray (CR) energy are included in the jet and we use the two-fluid formalism to model the CR component. We explore a wide range of cluster merger and jet parameters. We discuss the formation of various wide-angle-tail and X-shaped sources in the early evolution of the jet and merger. During the last phase of the evolution, we find that the CR material efficiently permeates the central region of the cluster reaching radii of ∼1–2 Mpc within ∼5–6 Gyr, depending on the merger mass ratio. We find that solenoidal turbulence dominates during the binary merger and we explore the possibility for the CR jet material to be reaccelerated by super-Alfvènic turbulence and contribute to cluster scale radio emission. We find high volume fractions, ≳70%, at which the turbulent acceleration time is shorter than the electron cooling time. Finally, we study the merger shock interaction with the CRe material and show that it is unlikely that this material significantly contributes to the radio relic emission associated with the shocks. We suggest that multiple jet outbursts and/or off-center radio galaxies would increase the likelihood of detecting these merger shocks in the radio due to shock reacceleration.

Microstructures and mechanical properties of a novel Al-5Mg-3Zn alloy with the combined additions Sc and Zr

The study investigated the impact of Sc and co-addition of Sc and Zr on the dispersoids, subsequent grain structures and aging precipitations, and the ultimate mechanical properties of Al-5Mg-3Zn-xSc-yZr (x + y = 0.2wt.%) alloys were studied. The results indicate that the co-addition of Sc and Zr produces the highest number density of dispersoids among the three alloys. The Al-5Mg-3Zn alloy mainly comprises fully recrystallized equiaxial grains (close to 100%) after solution treatment. In contrast, the recrystallization ratio of Al-5Mg-3Zn-0.1Sc-0.1Zr remarkably decreases to 9% owing to the presence of fine and dense Al3M dispersoids to impede the mobility of sub-grain boundaries. Adding the Sc element alone reduces the number density of the T-Mg32(Al, Zn)49 and enhances their size during the subsequent aging treatment, while the co-addition of Sc and Zr elements shows an opposite trend. The primary factor contributing to this result is that the microalloying of Sc and co-addition of Sc and Zr affects the diffusion of Mg and Zn solute atoms in Al-5Mg-3Zn alloys. Consequently, the peak-aged Al-5Mg-3Zn-0.1Sc-0.1Zr alloys exhibit a yield strength of 481MPa, an ultimate tensile strength of 547MPa, and an elongation of 12%, which is superior to the reported Al-5Mg-3Zn alloys. The good strength-ductility synergy can be attributed to the combination of a high number density of dispersions, grain refinement, and high-volume fraction nanoprecipitates.