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This article reviews the research and development focus of metallic glasses in the field of biomedical applications. Metallic glasses exhibit a short-range ordered and long-range disordered glassy structure at the microscopic level, devoid of structural defects such as dislocations and grain boundaries. Therefore, they possess advantages such as high strength, toughness, and corrosion resistance, combining characteristics of both metals and glasses. This novel alloy system has found applications in the field of biomedical materials due to its excellent comprehensive performance. This review discusses the applications of Ti-based bulk metallic glasses in load-bearing implants such as bone plates and screws for long-term implantation. On the other hand, Mg-based metallic glasses, owing to their degradability, are primarily used in degradable bone nails, plates, and vascular stents. However, metallic glasses as biomaterials still face certain challenges. The Young's modulus value of Ti-based metallic glasses is higher than that of human bones, leading to stress-shielding effects. Meanwhile, Mg-based metallic glasses degrade too quickly, resulting in the premature loss of mechanical properties and the formation of numerous bubbles, which hinder tissue healing. To address these issues, we propose the following development directions: (1) Introducing porous structures into titanium-based metallic glasses is an important research direction for reducing Young's modulus; (2) To enhance the bioactivity of implant material surfaces, the surface modification of titanium-based metallic glasses is essential. (3) Developing antibacterial coatings and incorporating antibacterial metal elements into the alloys is essential to maintain the long-term effective antibacterial properties of metallic biomaterials. (4) Corrosion resistance must be further improved through the preparation of composite materials, while ensuring biocompatibility and safety, to achieve controllable degradation rates and degradation modes. [ABSTRACT FROM AUTHOR]

Pure titanium is an ideal material for tissue replacements and implant materials for its superior biocompatibility and corrosion resistance, but its limited strength remains a major obstacle to its wide applications. A promising strategy for enhancing the strength is to alloy the pure titanium with oxygen. Herein, we reported an oxygen solid solution strengthening for pure titanium by achieving a titanium-oxygen (Ti–O) alloy using ball milling (BM) and spark plasma sintering (SPS). The effect of oxygen contents, ranging from 0.33 to 2.08 wt%, on the mechanical properties of pure titanium was systematically investigated. Experimental results indicate that the Ti–O alloy with the oxygen content of 1.95 wt% reached an ultrahigh yield strength of 2026 MPa and showed a large ductility of 11.2% in compression. According to the quantified analysis of strengthening mechanisms, solid solute oxygen atoms are responsible for the balance of superior yield strength and ductility of the Ti–O alloys. • The titanium-oxygen (Ti–O) alloys with ultrahigh strength and excellent ductility were prepared by ball milling and spark plasma sintering processes without any precious elements or heat treatment. • Outstanding properties of Ti-1.95O alloys are achieved with an ultrahigh compressive yield strength of 2026 MPa and good ductility of 11.2%. • The Ti-1.95O alloy overcomes the strength-ductility dilemma, resulting in the unexpected and dramatic increase in the ductility accompanied by increasing strength. [ABSTRACT FROM AUTHOR]

Oxygen solid solution reinforced Ti–O alloys with high strengths and good ductility were designed and synthesized via mechanical milling and spark plasma sintering (SPS) processes. The grain size and dispersion state of the Ti–O alloys were optimized by regulating the milling time of the composite powders. Outstanding properties were achieved by 4 h milling with a yield strength of 1082 MPa, 100% higher than that of commercially pure titanium (CP–Ti). According to the quantified results of the strengthening mechanism, fine grains are responsible for the balance of superior strength and ductility of the Ti–O alloy. • A novel Ti–O alloy with excellent mechanical properties was developed based on the grain refinement and solid-solution strengthening by oxygen. • The Ti–O alloy presents the yield strength of 1082 MPa and the ductility of ∼30%, which is 100% higher than that of the widely used CP–Ti. • The Ti–O alloy shows a excellent biocompatibility, which is similar with pure titanium. [ABSTRACT FROM AUTHOR]

Biodegradable metallic glasses are used as disposable green devices whose constituents decompose into harmless byproducts, leaving no residual waste and requiring no removal surgery. Here, the large size Ca-based (Ca 65 Mg 15 Zn 20) bulk metallic glasses (BMGs) were fabricated by consolidating gas-atomized metallic glassy alloy powder using a spark plasma sintering (SPS) technique. The effects of sintering temperature on structure, mechanical properties, and biodegradation rate of the developed Ca-based BMGs in Hank's solution were evaluated. The high-strength consolidated samples with a fully glassy phase and suitable biodegradation rate were produced by the SPS process at a sintering temperature of 120 °C with a loading pressure of 600 MPa. The Ca–Mg–Zn bulk metallic glass alloys developed by the SPS process can offer excellent properties and satisfy large sample-size requirements, which opens possibilities of application as biodegradable materials. • The large-size degradable Ca-based (Ca 65 Mg 15 Zn 20) bulk metallic glasses (BMGs) with good strength of 226 MPa were prepared by spark plasma sintering process. • This process produced Ca 65 Mg 15 Zn 20 BMGs exhibit best mechanical properties and degradable rate when the sintering temperature was set to 120 °C. • Crystal phases appeared in the Ca 65 Mg 15 Zn 20 BMGs with increasing the sintering temperature, resulting in the decrease in the strength and corrosion resistance. [ABSTRACT FROM AUTHOR]

The high strength and low cost of titanium alloys have led to the development of these alloys for aerospace applications. In this study, ultra-high-strength Ti–N alloys were fabricated by ball-milling (BM) and spark plasma sintering (SPS), and the effects of the nitrogen content on the microstructure and mechanical properties of the alloys were studied. TiN powder was used as the raw material for doping the alloys with N atoms, and the N content was controlled by tuning the amount of TiN powder added. The yield strength of the Ti–N alloys increased with an increase in the N content and surpassed 2000 MPa when the N content reached 2.66 wt%. Quantitative analysis using the Hall-Petch equation and Labusch model demonstrated that fine-grain strengthening and solution strengthening worked in synergy to enhance the strength of the Ti–N alloys. The ultra-high-strength Ti–N alloys can be applied in the aerospace field for structure use, such as aircraft engines, fasteners, and burn-resistant materials. The preparation of novel Ti–N alloys validates the theoretical application of ubiquitous elements in titanium alloys. • The fully dense Ti–N alloys were fabricated successfully by one-step consolidation process via SPS technology. • Ultra-high yield strength Ti–N alloy of 2012 MPa was achieved when the N content was 2.66 wt%. • The quantitative analysis revealed the main strengthening mechanisms of the Ti–N alloys were solution strengthening and fine-grained strengthening. • The fracture mode affecd by the nitrogen of the titanium alloys was studied. microporous polymeric and cleavage. [ABSTRACT FROM AUTHOR]

• A novel Ti-O alloy with ultrahigh oxygen content is developed based on the solid-solution strengthening mechanism. • This alloy presents a yield strength of 1005 MPa and a ductility of 37%, which is among the best performance in titanium alloys. • The ball milling influences the mechanical behaviors of the alloy via tuning the grain size distribution. Element substitution by light, economic, and innoxious components has been a promising strategy to improve the mechanical performances of Ti alloys. In this study, we develop a novel Ti-O alloy using ball milling (BM) and spark plasma sintering, which exhibits an excellent yield strength, 150% higher than that of commercially pure titanium and similar to that of the commercial Ti-6Al-4V alloy. In addition, the microstructure of the Ti-O alloy can be controlled by simply tuning the ball-to-powder ratio in the BM. An optimization is carried out, leading to a uniform distribution of the crystalline grains and refined grain size. Consequently, both yield strength and ductility can be enhanced. This study not only reveals the mechanism of microstructure refinement and homogenization in titanium alloys by the BM, but also provides a feasible strategy for the advancement of high-performance titanium alloys. [ABSTRACT FROM AUTHOR]

Mg–Zn–Ca bulk metallic glasses have emerged as a new biodegradable metal due to the excellent mechanical properties and good biocompatibility. In this study, we prepared nano Fe particles reinforced Mg 66 Zn 30 Ca 4 bulk metallic glass composites via spark plasma sintering. Nano Fe particles covered on the surface of Mg 66 Zn 30 Ca 4 glassy powder and formed a core-shell microstructure. We investigated the influence of different contents of Fe on strength and electrochemical behavior of the sintered composites. The strength increased from 574 MPa to 765 MPa with different contents of Fe. Moreover, with the addition Fe, the standard potential of Mg–Zn–Ca bulk metallic glasses improved 0.10 V and 0.14 V in Hank's and Saliva solutions, respectively. Thus, both of strength and corrosion resistance have significantly enhanced with the addition of Fe. In vitro cells experiment also proved that the materials are non-toxic, and it's beneficial to cells proliferation by adding Fe nanoparticles. The Fe@Mg 66 Zn 30 Ca 4 BMG composites with high strength and controllable degradation can be considered a promising candidate for degradable implant materials. • Fe nanoparticles as reinforcement covered on the surface of Mg 66 Zn 30 Ca 4 and formed Fe@Mg 66 Zn 30 Ca 4 core-shell structure composites. • The strength increased from 574 MPa to 765 MPa with contents of Fe from 0 to 10%.and the corrosion resistance also increased with the addition of Fe. • The composites greatly improve the mechanical properties, corrosion resistance and biocompatibility. [ABSTRACT FROM AUTHOR]

[Display omitted] • A non-toxic Zn-0.8Li-0.4Mn alloy is designed and prepared. The synergistic enhancement of strength and plasticity of Zn-0.4Mn-0.8Li alloy is achieved through hot rolling, with an ultimate tensile strength of 449.1 MPa and an elongation rate exceeding 75%. • A correlation between alloy deformation and the corrosion mechanism of Zn-0.4Mn-0.8Li alloys is revealed. The application of biodegradable Zn-based vascular alloy stents proves to be an ideal solution for addressing cardiovascular diseases. In this work, a Zn-0.8Li-0.4Mn alloy is designed with no biological toxicity, and optimized microstructure and properties through a hot rolling process. The resulting alloy shows a combined enhancement in both mechanical strength and resistance to corrosion. Noteworthy is the effectiveness of rolling deformation in refining alloy grains, promoting the uniform distribution of precipitates, and enhancing strength and ductility. After 90 % deformation, the Zn-0.8Li-0.4Mn alloy demonstrates excellent mechanical properties, with peak yield strength and ultimate tensile strength of 406.0 MPa and 449.1 MPa, respectively, and elongation exceeding 75 %. Corrosion studies indicate a relationship between the degradation rate increase and grain refinement, with the primary corrosion mechanism being pitting corrosion. The corrosion product Li 2 CO 3 exhibits high stability, providing a passivation effect on the alloy surface. This work establishes a theoretical foundation and practical reference for the development of new biodegradable Zn-based alloys tailored for biomedical applications. [ABSTRACT FROM AUTHOR]

Highlights Due to the exceptional flame retardancy, environmental protection, cost‐effectiveness, and ease of processing, halogen‐free flame‐retardant polyethylene (PE) composites are attracting wide attention. However, the addition of halogen‐free flame retardants usually leads to significantly decreased mechanical properties of PE composites, which greatly limits its application. Herein, we report a halogen‐free flame‐retardant PE/ethylene‐vinyl acetate copolymer composite (PE/EVA) with excellent flame retardancy and mechanical properties by combining compatibilizer, crosslinking agent, and carbon fiber. The presence of compatibilizer not only improves the compatibility of halogen‐free flame retardants and matrix, but also interacts with the crosslinking agent to form a cladding structure on the surface of carbon fiber. The enhanced interaction between carbon fiber surface and matrix then results in significantly enhanced flame retardancy and mechanical properties of the composite. Specifically, adding 4 phr compatibilizer, 0.5 phr crosslinking agent, and 10 phr carbon fiber will lead to the halogen‐free flame‐retardant PE/EVA composite with a UL‐94 V‐1 level, limiting oxygen index of 27.1, and an increased tensile strength by 84.02% reaching 19.12 MPa. Moreover, further carbon fiber surface modification can further enhance the flame retardancy of the composite probably due to a synergistic flame‐retardant effect caused by the surface modified nitrogen and silicon elements. As a result, the composite achieves UL‐94 V‐0 level and the limiting oxygen index of 27.7 with well‐retained high tensile strength of 15.19 MPa. This work provides a practical strategy for enhancing the flame retardancy and mechanical property of PE‐based composite simultaneously. Compatibilizer interacts with crosslinking agent to form a cladding structure on the surface of carbon fiber. Crosslinking agent promotes the formation of chemical bonds between modified carbon fiber, compatibilizer, and matrix. Carbon fiber surface modification can enhance the flame retardancy of the composite due to the synergistic flame‐retardant effect. [ABSTRACT FROM AUTHOR]

Abstract In this study, the number and size distribution characteristics of fine nanoscale precipitates and their effects on hydrogen diffusion and hydrogen induced ductility loss were investigated in X80 pipeline steel. The results showed that with the increase of vanadium content, more vanadium carbides precipitated in the tested steels and the proportion of precipitates with size less than 10 nm distinctly increased, which fixed a large amount of diffusible hydrogen atoms as effective traps. The hydrogen diffusion coefficient decreased from 5.12 × 10−6 cm2 s−1 in the vanadium-free V1 steel to 9.94 × 10−7 cm2 s−1 in the V4 steel with 0.13% V. In addition, for the tested steels containing vanadium, the hydrogen embrittlement gradually decreased with increasing nanoscale vanadium precipitates, which pinned the movable dislocations and weakened the hydrogen-enhanced localized plasticity. The V4 steel with 0.13% V had the best performance to resist to hydrogen induced ductility loss. [ABSTRACT FROM AUTHOR]

Chromium Nitride (CrN) coatings have widespread utilization across numerous industrial applications, primarily attributed to their excellent properties. Among the different methods for CrN coating synthesis, direct current magnetron sputtering (DCMS) has been the dominant technique applied. Nonetheless, with the expanded applications of CrN coatings, the need for enhanced mechanical performance is concurrently escalating. High-power impulse magnetron sputtering (HiPIMS), an innovative coating deposition approach developed over the past three decades, is gaining recognition for its capability of yielding coatings with superior mechanical attributes, thereby drawing significant research interest. Considering that the mechanical performance of a coating is fundamentally governed by its microstructural properties, a comprehensive review of CrN coatings fabricated through both techniques is presented. This review of recent literature aims to embark on an insightful comparison between DCMS and HiPIMS, followed by an examination of the microstructure of CrN coatings fabricated via both techniques. Furthermore, the exploration of the underlying factors contributing to the disparities in mechanical properties observed in CrN coatings is revealed. An assessment of the advantages and potential shortcomings of HiPIMS is discussed, offering insight into CrN coating fabrication. [ABSTRACT FROM AUTHOR]

High-entropy alloys (HEAs) have emerged as promising biomaterials owing to their favorable mechanical properties and resistance to corrosion. This investigation focuses on the impact of incorporating Si on the microstructure and properties of TiZrHfNbSi x HEAs. The inclusion of Si leads to the formation of complex compositional silicides, showing multiple structures as the Si content varies. At low Si content, the BCC-silicide eutectic structure blocks the expansion of the shear zone during the deformation process, accounting for the increase in strength. The TiZrHfNbSi 0.25 alloy presents a balanced combination of yield strength (∼1129 MPa) and plasticity (∼17 %). Additionally, TiZrHfNbSi 0.5 exhibited optimal corrosion resistance in Hank's balanced salt solution (I corr = 1.713 × 10−7 A cm−2, E corr = −0.327 V, 310 K) owing to the reduction in the number of protocells brought about by Si. The remarkable properties of TiZrHfNbSi x HEAs renders it a highly promising option for application of silicide reinforcement in biomedical materials. • The TiZrHfNbSi 0.25 alloy presents a balanced combination of compressive strength (∼1129 MPa) and plasticity (∼17 %). • The microstructure formation and strengthening mechanism of TiZrHfNbSi x alloys is revealed. • The TiZrHfNbSix alloys exhibit high corrosion resistance in Hanks' balanced salt solution. [ABSTRACT FROM AUTHOR]

A novel high-strength conductive Cu-based composite, utilizing AlCrCuFeNi 2.5 (Ni2.5) high-entropy alloy particles as the reinforcing phase, is synthesized through a combination of ball milling and spark plasma sintering processes. The mechanical and electrical properties of the composites are optimized by adjusting the composition. Under the synergistic effect of multiple strengthening mechanisms, the fabricated Cu-20 wt% Ni2.5 composites achieve an exceptional compressive strength of 920 MPa while maintaining an electrical conductivity of 44.3 % IACS (International Standard Copper Standard). The establishment of robust interface bonding between Ni2.5 reinforcement and Cu matrix stands as a pivotal assurance for the holistic performance of composites. Ni2.5 HEA is distinguished by good plasticity and high strength compared with traditional brittle reinforcements. An insight into the differences brought about by the distinctive dual-phase structure in terms of interfacial bonding, crack propagation, and performance is provided. It paves the way for selecting and projecting the composites for electrical contact applications, ushering in a realm of fresh possibilities. [ABSTRACT FROM AUTHOR]

To mimic the biomechanical properties of natural bone, the porous Ti 45 Zr 10 Cu 31 Pd 10 Sn 4 bulk metallic glass (BMG) with bone-like mechanical characteristics was developed by one step SPS method. In this work, the introduced pore contributions to the corrosion behavior in simulated body fluid and the biocompatibility of BMG were further explored. According to the findings, the porous BMG not only outperforms commercial Ti-based orthopedic implants (CP-Ti and Ti-6Al-4V) in terms of corrosion resistance, but also ranks among the porous biomedical alloys that have been reported. Simultaneously, in vitro investigations revealed that MC3T3 cells co-cultured with porous BMGs could multiply normally, indicating the porous BMG's remarkable biocompatibility. • The corrosion mechanism of porous BMG was studied by EIS and XPS. • The influence of porous structure on the biocompatibility of porous BMG was studied. • The porous BMG had better corrosion resistance than pure Ti and TC4 alloy. [ABSTRACT FROM AUTHOR]

In this work, the electronic, mechanical and thermodynamic properties of two polymorphs of LuAlB 4 ceramics (α -LuAlB 4 and β -LuAlB 4) were predicted through first-principles calculations. The formation enthalpy of α -LuAlB 4 and β -LuAlB 4 is −1.433 kJ/mol and −1.429 kJ/mol, respectively, indicating that LuAlB 4 ceramics are stable. Crystal structure and electronic structure analysis revealed that strong B–B bonds greatly contributes to the high hardness of LuAlB 4 ceramics. The analysis of state density showed that LuAlB 4 is a layered ternary boride with metallic properties. Elastic anisotropy indexes, 3D surface constructions and 2D projections of elastic modulus showed that the elastic anisotropy of α -LuAlB 4 is higher than β -LuAlB 4. In addition, the phonon dispersion curves verified the thermodynamic stability of LuAlB 4 ceramics. Finally, according to elastic constants and modulus, the Debye temperature, directional sound velocities and thermal conductivities of LuAlB 4 ceramics were discussed. • The metal characteristics of LuAlB 4 mainly composed of Lu- p , Lu- d , Al- p and B- p state decisions. • Judging by Poisson's ratio v and Pugh's modulus ratio G / B , the plasticity of LuAlB 4 is better than that of other Lu-B system ceramics that have been reported. • The elastic universal anisotropy index A U indicates that the order of elastic anisotropy is: α-LuAlB 4 > β-LuAlB 4. [ABSTRACT FROM AUTHOR]

Metallic glass-reinforced Cu-based composites offer a promising avenue for overcoming the trade-off between high strength and high electrical conductivity in materials. In this investigation, heterogeneous CuZrAl metallic glass-reinforced CuCrZr alloy composites are prepared through spark plasma sintering and a one-step hot pressing. The microstructural evolution of the composites during the preparation process and its correlation with mechanical and electrical properties are revealed. Grain refinement and dislocation accumulation in the CuCrZr alloy matrix resulted in strength gain and a trade-off in electrical conductivity. However, precipitation of the Cr-rich phase compensates for the loss of conductivity. Directional strengthening and toughening of the composites are achieved by inducing deformation of the CuZrAl metallic glass reinforcement in the undercooled liquid region to attain its ordered arrangement. Furthermore, the electrical and mechanical properties of the crystalline phase Cu 10 Zr 7 at the edge of metallic glass are predicted and investigated using first-principles calculations, with a focus on its impact on the performance of composites. A novel Cu-based metallic glass composites fabricated using an efficient processing approach offers valuable insights into material selection for electrical conductor applications. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, the number and size distribution of vanadium precipitates and their effects on hydrogen trapping efficiency and hydrogen-induced cracking (HIC) susceptibility were investigated in X80 pipeline steel. The results showed that as the vanadium content increased, the number of nanoscale vanadium precipitates clearly increased. Furthermore, the amount of hydrogen atoms trapped by vanadium precipitates gradually increased and the hydrogen diffusion coefficient decreased from 4.74 × 10 −6 cm 2 s −1 in the vanadium-free V0 steel to 8.48 × 10 −7 cm 2 s −1 in the V4 steel with 0.16% V, according to hydrogen permeation results. It also reduced the possibility of hydrogen atoms diffusing into the sites of harmful defects such as large-size oxides and elongated MnS inclusions, where cracks were caused more easily. In addition, the V3 steel with 0.12% V, containing the largest number of vanadium carbide particles of less than 60 nm, had the lowest HIC susceptibility. [ABSTRACT FROM AUTHOR]

Metal implants usually are regarded as the best choice to replace hard tissue, such as hip and knee joints, which is due to their excellent mechanical properties. However, osseointegration should be improved between the implant materials and the surrounding bone tissue. Surface modification is a solution to addressing this issue, in which electrochemical anodization is an easy and cost-effective method to fabricate the nanotubes on the implant surface. In this work, coral-like multi-component metal oxide nanotubes with micro/nano-textured on ultra-high strength TiZrNbTa highentropy alloy substrates that possess 2033 ± 81 MPa for yield strength and 6.9 % ± 1.3 % for plasticity have been successfully fabricated by anodization. Surface morphology, surface chemistry analyses, hydrophilicity, mechanical properties, and biocompatibility were studied in detail. In comparison, the addition of coral-like multi-component metal oxide nanotubes with micro/nano-topography on the TiZrNbTa surface reveals better biocompatibility than smooth TiZrNbTa, which provides a possibility as implant materials to apply. [Display omitted] • Combined the mechanical alloying with the spark plasma sintering technology, TiZrNbTa HEA substrate was fabricated. • The coral-like MONTs on TiZrNbTa HEA with hybrid micro/nano-topographies was fabricated by the anodic oxidation. • The TiZrNbTa HEA with hybrid micro/nano-topography shows better biocompatibility than bare TiZrNbTa HEA. [ABSTRACT FROM AUTHOR]

Grain refinement is perfectly efficient for improving strength, but accompanies by a dramatic loss of ductility. Here we report a bimodal grain size structure design by inducing ultra-high strength TiZrNbTa high entropy alloy (HEA) with nanoscale grain size into pure Ti with coarse grain size to achieve the strength-strain balance by establishing bimodal grain size distribution (BGSD). Through optimizing the TiZrNbTa HEA content, the 60 wt.% TiZrNbTa/Ti titanium matrix composite (TMC) exhibits a yield strength of 1426 ± 30 MPa, ultimate compressive strength of 2133 ± 88 MPa, and an acceptable compressive strain of 22.3% ± 1.8%, respectively. The compressive yield strength of 60 wt.% TiZrNbTa/Ti TMC is 3.6-fold for c.p. Ti (393.0 ± 7.1 MPa). The unusual high strength is attributed to the nanoscale grain size provided by TiZrNbTa HEA, and the acceptable compressive strain is obtained from the co-effect of coarse grain Ti and TiZrNbTa HEA. The excellent mechanical properties of 60 wt.% TiZrNbTa/Ti TMC undoubtedly greatly increase the possibility of its application as an orthopedic implant in the biomedical field. [Display omitted] • A bimodal grain size structure design is beneficial to the strength-ductility balance. • The strength and plasticity of TiZrNbTa/Ti MMCs achieve the best combination by the composition optimization of TiZrNbTa HEA. • The yield strength (1426 ± 30 MPa) of 60 wt% TiZrNbTa/Ti MMC with plasticity of 22.3% ± 1.9% is 3.6-fold for c.p. Ti (393.0 ± 7.1 MPa). [ABSTRACT FROM AUTHOR]

Cu/Cu-Zr-Al metallic glass composites (C/CMGCs) are high-strength conductive materials that have been synthesized by a combination of ball milling (BM) and spark plasma sintering (SPS). This study investigated how the rotational speed of BM process before SPS consolidation affects the microstructure, mechanical properties and electrical properties of fabricated bulk C/CMGCs were investigated. Increasing the BM speed significantly enhanced the mechanical strength while maintaining a high electrical conductivity. However, when the speed exceeded 375 rpm, the high centrifugal force hindered effective impact between the balls and powder to impede further performance optimization. Using the grain boundary strengthening strategy, nanocrystalline copper was strengthened by tuning the milling parameters. The simultaneous achievement of high conductivity and superhigh strength in the C/CMGCs will prompt further explorations of functionalized bulk metallic glass composites with vast untapped potentials. • Nanocrystalline Cu/Cu50Zr43Al7 composites were prepared by ball milling and spark plasma sintering. • Control of milling speed resulted in balanced mechanical and electrical properties. • The high mechanical strength is due to grain refinement of crystalline Cu phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metallic glass (MG)-particle-reinforced nanocrystalline CuCrZr alloys with ultrahigh strengths and good conductivities are synthesized via mechanical milling and spark plasma sintering. • Outstanding properties of composites are achieved with ultimate compressive strengths of 1099 ± 33 MPa and 1185 ± 29 MPa and high conductivities of 29.9 ± 0.8% IACS and 25.2 ± 0.6% IACS, respectively. • The strengthening and conductivity mechanisms of the composites are discussed to analyze the excellent mechanical and electrical properties. Metallic glass (MG)-particle-reinforced nanocrystalline CuCrZr alloys with ultrahigh strengths and good conductivities are designed and synthesized via mechanical milling and spark plasma sintering (SPS). The particle morphology and dispersion state of the CuZrAl MG reinforcement in the CuCrZr alloy matrix are optimized by regulating the milling time of the composite powders prior to SPS consolidation. Outstanding properties are achieved by 5 h and 10 h milling processes with ultimate compressive strengths of 1099 ± 33 and 1185 ± 29 MPa and high conductivities of 29.9 ± 0.8% IACS and 25.2 ± 0.6% IACS, respectively. According to the quantified results of strengthening and conductivity mechanisms, MG reinforcements and ultrafine grains are responsible for the balance of superior strength and conductivity of the composites. [ABSTRACT FROM AUTHOR]