Subsequent Spark Plasma Sintering Research Articles

Microstructure and constitutive modeling of an ultrafine-grained refractory high-entropy alloy fabricated by powder metallurgy

In the present study, a novel AlCr0.3FeMoNbTiV2 alloy was prepared by means of mechanical alloying and subsequent spark plasma sintering, resulting in an ultrafine-grained (UFG) microstructure consisting of a bcc matrix phase with an average grain size of 0.32 μm accompanied by Ti carbide, Laves phases, and minor contents of Al2O3. Excellent thermal stability was exhibited by the alloy, since no considerable phase transformations were observed after a heat treatment at 1350 °C for 16 h, beyond microstructural coarsening, as can be appreciated from the increase of the average bcc grain size up to 1.50 μm. Compression tests were performed at elevated temperatures (950 – 1100 ºC) at strain rates ranging 0.0005 – 0.01 s-1. According to the constitutive analysis of the peak stress using the hyperbolic sine law, an experimental creep exponent of 2.17 was obtained, which indicates that deformation is mainly controlled by grain boundary sliding, as typically observed in UFG materials, with a large apparent activation energy of 527.7 kJ·mol-1, superior to that of other RHEAs reported in literature.

Effect of V Content on Corrosion Behavior of Al-V Alloys Produced by Mechanical Alloying and Subsequent Spark Plasma Sintering

Abstract Al-V alloys produced via high-energy ball milling have been reported to show simultaneous improvement of corrosion resistance and mechanical properties compared to traditional Al alloys. In these alloys, V content plays a crucial role in increasing or decreasing corrosion resistance. Therefore, the effect of V and microstructure on corrosion of high-energy ball milled and subsequently spark plasma sintered Al-xV alloys (x = 2, 5, 10 at.%) has been studied. Cyclic potentiodynamic polarization tests and electrochemical impedance spectroscopic analysis revealed that increments of V content up to 5 at. % enhanced the corrosion resistance of the alloy. However, highly heterogeneous microstructure in Al-10 at.%V resulted in significant localized corrosion over the immersion time. The electrochemical impedance spectroscopy studies over 14 days of immersion revealed underlying corrosion mechanisms.

Processing and optical behavior of dense (Hf,Zr)B2 solid solutions for solar energy receivers

While individual borides and, more recently, quinary High Entropy Transition Metal Borides have been investigated, the fabrication and characterization of bulk binary to quaternary solid solutions are barely explored. In this work, dense (Hf0.5Zr0.5)B2 is produced by Spark Plasma Sintering (SPS) from powders prepared by Self-propagating High-temperature (SHS). SHS produced a multiphase product, whose secondary phases are fully converted into the desired diborides during the subsequent SPS step. Optical properties of (Hf0.5Zr0.5)B2 are evaluated for the first time with focus on the possible use as novel high-temperature solar thermal absorber, by hemispherical reflectance measurements and calculation of solar absorptance, temperature-dependent spectral selectivity and absorber opto-thermal efficiency at various solar concentration ratios. To optimize the material, a chemically etched surface texture was realized to modify the optical properties. The etched sample showed a higher solar absorptance (0.71) and a lower spectral selectivity than the unetched one, with consequent higher opto-thermal efficiency at all temperatures for solar concentration ratios 1000 ÷ 3000, while at lower concentration ratios and temperatures >1400 ÷ 1600 K, the unetched sample shows the highest efficiency. These results show the promising properties of binary diborides for solar thermal applications.

Planar defects and strain distributions in polycrystalline BaFe2As2 superconductors synthesized by mechanochemical methods

In this study, the microstructure of polycrystalline Co-doped BaFe2As2 superconducting bulks was comprehensively analyzed. The synthesis process involved ball milling and subsequent spark plasma sintering (SPS). A strong correlation between the microstructure and synthesis conditions was observed. Specifically, when mechanochemical synthesis of raw metal powders was carried out at a ball milling energy (EBM) of 100 MJ/kg, the resulting Co-BaFe2As2 bulk contained nanograins with a high density of planar defects and exhibited a high critical current density (Jc) under both magnetic and self-fields. The findings suggest that planar defects are one of the influential factors on the superconducting properties. Atomic-resolution microstructural characterization revealed that the planar defects are parallel to (001) and exhibit distinctive atomic arrangements. Atomic-resolution elemental mappings displayed a remarkable barium concentration in planar defects and grain boundaries compared to the BaFe2As2 matrix. Local strain fields were also observed around planar defects, especially near their edges. These nanoscale strain fields could be considered as volumetric pinning centers, and effectively pin flux vortices in the random crystal orientation, thereby increasing Jc in the Fe-based superconducting bulk. Additionally, an extended investigation was performed to include a K-doped BaFe2As2 bulk that exhibits similar planar defects. Based on the results of the microstructural analysis, speculations were mode on the evolution process of the microstructure during the preparation of BaFe2As2 bulks.

Simultaneously Enhanced Thermoelectric and Mechanical Performance in SnSe-Based Nanocomposites Produced via Sintering SnSe and KCu7S4 Nanomaterials.

Both thermoelectric and mechanical properties are important to the practical applications of thermoelectric materials. Herein, we develop a strategy for alloying KCu7S4 to improve the dimensionless figure of merit (zT), compressive strength, and Vickers hardness of polycrystalline SnSe. Through chemical synthesis and particle mixing in solutions, powders with SnSe nanoparticles and KCu7S4 nanowires are produced, and the subsequent spark plasma sintering triggers the reaction between the two chalcogenides, resulting in the formation of Cu2SnSe3 nanoparticles and substitution of Cu and S in the SnSe matrix. The composition tuning and secondary phase formation effectively enhance the power factor and diminish the lattice thermal conductivity, leading to a maximum zT of 1.13 at 823 K for the optimal sample, which is improved by 135% over that of SnSe. Simultaneously, the compressive strength and hardness are also enhanced, as exemplified by a high compressive strength of 135 MPa that is enhanced by ∼81% compared to that of SnSe. The current study demonstrates effective composite and composition design toward enhanced thermoelectric and mechanical performance in polycrystalline SnSe.

Preparation of polymer-derived SiOC-Cu ceramic composites and their tribological performance

Cu-containing silicon oxycarbide (SiOC) ceramic composites have been prepared by thermal pyrolysis of polymeric precursors and subsequent spark plasma sintering at 1600 °C. The resulting composites consist of SiO2, SiC, free carbon, and Cu-Si alloys. The microstructure of the composites has been identified via optical microscope and SEM. The mechanical properties, including the Vickers hardness, nano-indentation hardness, and Young’s modulus, of the SiOC composites have been assessed via indentation methods. The effects of Cu content on the tribological properties of the composites have additionally been investigated under different sliding frequencies against Al2O3 spheres at room temperature. It is shown that the introduction of the Cu-Si alloys is effective in reducing the friction coefficient of the material system, which decreases linearly from 0.27 of monolithic SiOC to 0.15 of SiOC with 7 wt% Cu content at 1 Hz. Raman spectroscopy has highlighted the friction-driven evolution of the free carbon phase in the SiOC ceramics. Finally, a correlation between the sliding frequency, Cu-Si content, and tribological properties of SiOC is established.

Effect of Y2O3 nanoparticles on enhancing microstructure and mechanical properties of oxide dispersion strengthened W alloy

Dispersion of oxide nanoparticles in W, leading to the dispersion strengthening of W alloys, has emerged as a viable strategy to overcome the brittleness of W. In particular, the introduction of stable Y2O3 as a secondary phase refines the grain and enhances the densification of W, leading to an increase in the density of sintered alloy. Thus, analyzing the composite effects of Y2O3 on the alloy, which has homogeneous dispersion of Y2O3 nanoparticles, can allow enhanced mechanical properties of the W-Y2O3 alloy. However, to date, most studies have focused on synthesis methodology for nanocomposites, which is advantageous to grain refinement and dispersion. It is worth paying attention to the interaction in the W-Y2O3 system, such as the ternary oxide system (W-Y-O) with a low eutectic temperature and the possibility of liquid-phase sintering, which has been reported a few. In this study, the effect of Y2O3 nanoparticles on the microstructure and micro-Vickers hardness of W was experimentally evaluated. W-Y2O3 alloys with precisely controlled compositions from 1 wt% to 10 wt%Y2O3 were successfully fabricated using an ultrasonic spray pyrolysis process and a subsequent spark plasma sintering. The proposed process yielded Y2O3 nanoparticles with uniform dimensions and distributions even after sintering. Furthermore, the formation of Y2WO6 and a liquid-phase sintered structure, as products of the interaction between W and Y2O3 depending on the Y2O3 fraction, were observed, and thermodynamical formation routes were suggested. Evidently, the W-2wt%Y2O3 sintered alloy, with uniformly dispersed Y2O3 nanoparticles (<50 nm), exhibited an improved hardness of 7.21 ± 0.15 GPa, as the W grains were refined to approximately 760 nm, and their density increased to 96.48%.

The impressive improvement of CoCrFeMnNi high entropy alloy mechanical properties and pitting corrosion resistance by incorporation of carbon nanotube reinforcement

CoCrFeMnNi high entropy alloy without carbon nanotube (referred to as HEA) and with 0.2 wt% CNT (called HEA + CNT) were successfully synthesized through mechanical alloying and subsequent spark plasma sintering. The samples' phase composition, microstructure, mechanical properties, and corrosion performance were investigated. XRD results showed that the addition of CNT leads to a decrease in crystallite size, reducing it from 209 nm in HEA to 190 nm in HEA + CNT. FESEM results revealed a relatively uniform distribution of smaller carbide phases in the structure of HEA + CNT sample. The addition of CNT increased the ultimate compressive stress (UCS) from 1850 MPa for HEA to 2510 MPa for HEA + CNT. Cyclic polarization results demonstrated higher pitting corrosion resistance in HEA + CNT nanocomposite, where the pitting potentials for HEA and HEA + CNT were equal to 0.127 and 0.201 V vs. SCE, respectively. The CNT addition promoted the repassivation process of the pits in HEA + CNT sample.

Synthesis and sintering of MAX phases in the Zr–Al–C system

AbstractIn this paper, synthesis and sintering of MAX phases in the Zr–Al–C system is described. Different mixtures of initial Zr/Al/C and Zr/Al/ZrC powders were used to synthesize the MAX phases of Zr2AlC and Zr3AlC2 compositions by a combined method (high‐temperature sintering followed by spark plasma sintering [SPS]). The highest content of the Zr3AlC2 MAX‐phase was obtained using initial Zr/Al/ZrC powders in a component ratio of 1:1.5:2—51.1 vol.%. The optimal temperature for the synthesis of a material based on the Zr2AlC MAX phase is 1525°C, and a material based on Zr3AlC2 is 1575°C. During subsequent SPS at a temperature of 1500°C, a pressure of 50 MPa, within 5 min, it was obtained a material containing up to 71.1 vol.% Zr3AlC2. The relative density of the samples synthesized and consolidated by the SPS method reaches 98.9%. The structure of the obtained synthesized MAX materials includes elongated grains of the composition Zr2AlC and Zr3AlC2, which determines their high strength. The influence of the sintering time and temperature on the formation of the MAX phase of Zr3AlC2 from the initial powders of Zr/Al/ZrC is shown. Zirconium carbide, as an intermediate phase, is always present in the final products. Due to the large evaporation of aluminum, the ZrAl2 phase is also present in the synthesis products. An excess of aluminum contributes to the greatest formation of the Zr2AlC and Zr3AlC2 phases during the combined synthesis.

Fabrication of High-Entropy Alloys Using a Combination of Detonation Spraying and Spark Plasma Sintering: A Case Study Using the Al-Fe-Co-Ni-Cu System

The use of pre-alloyed powders as high-entropy alloy (HEA) coating precursors ensures a predetermined (unaltered) elemental composition of the coating with regard to the feedstock powder. At the same time, it is interesting to tackle a more challenging task: to form alloy coatings from powder blends (not previously alloyed). The powder-blend-based route of coating formation eliminates the need to use atomization or ball milling equipment for powder preparation and allows for the introduction of additives into the material in a flexible manner. In this work, for the first time, a HEA was obtained using detonation spraying (DS) followed by spark plasma sintering (SPS). A powder mixture with a nominal composition of 10Al-22.5Fe-22.5Co-22.5Ni-22.5Cu (at.%) was detonation-sprayed to form a multicomponent metallic coating on a steel substrate. The elemental composition of the deposited layer was (9 ± 1)Al-(10 ± 1)Fe-(20 ± 1)Co-(34 ± 1)Ni-(27 ± 1)Cu (at.%), which is different from that of the feedstock powder because of the differences in the deposition efficiencies of the metals during DS. Despite the compositional deviations, the deposited layer was still suitable as a precursor for a HEA with a configurational entropy of ~1.5R, where R is the universal gas constant. The subsequent SPS treatment of the substrate/coating assembly was carried out at 800–1000 °C at a uniaxial pressure of 40 MPa. The SPS treatment of the deposited layer at 1000 °C for 20 min was sufficient to produce an alloy with a single-phase face-centered cubic structure and a porosity of &lt;1%. Interestingly, the hardness values of the as-sprayed and SPS-treated coatings were close to each other (~320 HV0.3). The hardness of the coatings measured in two perpendicular directions did not differ significantly. The features of the DS–SPS route of the formation of HEA coatings and its potential applications are discussed.

Realizing High Thermoelectric Performance in n‐Type Se‐Free Bi2Te3 Materials by Spontaneous Incorporation of FeTe2 Nanoinclusions

Bi2Te3‐based materials have drawn much attention from the thermoelectric community due to their excellent thermoelectric performance near room temperature. However, the stability of existing n‐type Bi2(Te,Se)3 materials is still low due to the evaporation energy of Se (37.70 kJ mol−1) being much lower than that of Te (52.55 kJ mol−1). The evaporated Se from the material causes problems in interconnects of the module while degrading the efficiency. Here, we have developed a new approach for the high‐performance and stable n‐type Se‐free Bi2Te3‐based materials by maximizing the electronic transport while suppressing the phonon transport, at the same time. Spontaneously generated FeTe2 nanoinclusions within the matrix during the melt‐spinning and subsequent spark plasma sintering is the key to simultaneous engineering of the power factor and lattice thermal conductivity. The nanoinclusions change the fermi level of the matrix while intensifying the phonon scattering via nanoparticles. With a fine‐tuning of the fermi level with Cu doping in the n‐type Bi2Te3–0.02FeTe2, a high power factor of ~41 × 10−4 Wm−1 K−2 with an average zT of 1.01 at the temperature range 300–470 K are achieved, which are comparable to those obtained in n‐type Bi2(Te,Se)3 materials. The proposed approach enables the fabrication of high‐performance n‐type Bi2Te3‐based materials without having to include volatile Se element, which guarantees the stability of the material. Consequently, widespread application of thermoelectric devices utilizing the n‐type Bi2Te3‐based materials will become possible.

SYNTHESIS, MICROSTRUCTURE AND THERMOELECTRIC PROPERTIES OF COMPOSITE MATERIAL Bi2Te2.7Se0.3Teδ OBTAINED FROM ASYMMETRIC

Composite materials Bi2Te2.7Se0.3 /Teδ with varying concentration (δ = 0.15; 0.2; 0.25 and 0.3) were obtained by solvothermal synthesis of the initial powders and their subsequent spark plasma sintering. During the sintering process, the samples are textured, as a result of which the lamellar grains are arranged in layers perpendicular to the direction of pressure application during sintering (the direction of the texture axis). At magnification, the concentration of over-stoichiometry tellurium decreases the degree of texturing. The concentration of tellurium does not affect the average grain size. Super-stoichiometric tellurium is distributed along the grain boundaries, as a result of which a structure characteristic of composite materials is formed. The release of tellurium at the grain boundaries leads to a change in the thermoelectric properties of the obtained materials. The electrical resistivity naturally increases, and the total thermal conductivity decreases with an increase in the concentration of overstoichiometry tellurium.

Synthesis and characterization of high entropy carbide-MAX two-phase composites

In the present work, the formation of high entropy MAX phase during mechanical alloying and subsequent spark plasma sintering (SPS) of two powder mixtures with (HfZrNbTiTa)3SiC2 and (HfZrNbTiTa)3(SiAl)1.1C1.95 stoichiometries is investigated. The results indicate that a high entropy carbide (HEC) with cubic HfC-prototype structure is formed for both compositions after 7 h of mechanical alloying. The microstructural observations indicate the nano-sized nature of the as-milled powders. For both specimens, consolidation at high temperatures leads to a phase transition from single HEC to HEC-MAX complex. Ultrahigh microhardness values of 11 ± 2 GPa and 8 ± 2 GPa were obtained for the consolidated (HfZrNbTiTa)3SiC2 and (HfZrNbTiTa)3(SiAl)1.1C1.95 specimens, respectively. The results also revealed that the (HfZrNbTiTa)3(SiAl)1.1C1.95 exhibits ferromagnetic behavior with low magnetization saturation of only 1.709 emu/g, while (HfZrNbTiTa)3SiC2 shows a ferromagnetic behavior with relatively low coercivity and magnetization saturation. Finally, the findings provide a new route to tailor mechanical properties of HEC-MAX complexes by controlling the evolution of MAX phase.

Effects of hafnium content on microstructures and properties of newly developed (Ti,Hf)(C,N) ceramics

In this study, novel (Ti,Hf)(C,N) ceramics with varying hafnium contents were fabricated via carbothermal reduction–nitridation and subsequent spark plasma sintering. The influence of Hf addition on the mechanical properties, wear properties, and corrosion resistance of the (Ti,Hf)(C,N) ceramics was systematically studied. The introduction of Hf promoted the sintering densification of the ceramics in the sintering process. The prepared (Ti,Hf)(C,N) ceramics exhibited excellent mechanical and wear properties owing to refinement and solution-strengthening mechanisms. The (Ti0.9,Hf0.1)(C0.5,N0.5) ceramic demonstrated higher Vickers hardness and fracture toughness, measuring 1997 HV5 and 4.28 MPa m1/2, respectively, compared to the pure Ti(C0.5,N0.5) ceramic which exhibited values of 1635 HV5 and 3.94 MPa MPa m1/2. The wear scar depth of the (Ti0.9,Hf0.1)(C0.5,N0.5) ceramic sample was 57.36% to that of the Ti(C0.5,N0.5) ceramic. Additionally, the addition of Hf improved the corrosion resistance of (Ti,Hf)(C,N) ceramics in a 0.5 M NaOH solution. The potential applications of (Ti,Hf)(C,N) ceramics include machining tools and wear-resistant parts.

Polymer-derived SiOC ceramics: A potential catalyst support controlled by the sintering temperature and carbon content

A series of silicon oxycarbide ceramics with varying carbon content from ca. 10 wt% to ca. 40 wt% were prepared by thermal pyrolysis of four commercially available polysiloxanes and subsequent spark plasma sintering (SPS) at 1200 °C, 1400 °C, and 1600 °C. The results showed that the high carbon content led to a porous microstructure, and for SiOC with ca. 40 wt% carbon content, its porosity and specific surface area at 1600 °C reached 34% and 262 m2/g, respectively. The electrochemical behavior of materials was evaluated. It was shown that SiOC has a certain degree of electrocatalytic activity, and the sample with 10 wt% carbon content obtained at 1200 °C exhibited an overpotential of 450 mV vs. RHE at 10 mA·cm−2 in acid medium. Finally, it was analyzed that the electrochemical behavior of SiOC is closely related to the phase composition and microstructure of the resulting ceramics.

Investigation of the Effect of Molybdenum Silicide Addition on the Oxidation Behavior of Hafnium Carbonitride

In this study, the oxidation stability up to 1000 °C in air of the Hf(C,N)-MoSi2 composites was explored under non-isothermal and isothermal conditions. Composites with 1, 5, 10, and 20% volume fractions were produced by low-energy ball milling and subsequent spark plasma sintering. Differential scanning calorimetry (DSC) and thermogravimetric (TG) coupled with mass spectrometry were used to reveal the staging of the oxidation process depending on the additive content. It was found that samples containing 1 and 5 vol% MoSi2 had the lowest weight gain and the best oxidation behavior. The results of this study were supported by microstructural and phase analyses of the samples after isothermal treatment in a furnace. The samples with the lowest molybdenum disilicide content had a dense and thin protective oxide film on the surface, consisting of hafnium orthosilicate and monoclinic HfO2. The increase in the amount of MoSi2 contributed to the formation of a loose and porous oxide layer due to the increase in the concentration of volatile MoO3. However, all samples exhibited higher oxidation resistance compared to the pure Hf(C,N).

Effect of Volume Fraction of Reinforcement on Microstructure and Mechanical Properties of In Situ (Ti, Nb)B/Ti2AlNb Composites with Tailored Three-Dimensional Network Architecture.

The mechanical properties of (Ti, Nb)B/Ti2AlNb composites were expected to improve further by utilizing spark plasma sintering (SPS) and inducing the novel three-dimensional network architecture. In this study, (Ti, Nb)B/Ti2AlNb composites with the novel architecture were successfully fabricated by ball milling the LaB6 and Ti2AlNb mixed powders and subsequent SPS consolidation. The influence of the (Ti, Nb)B content on the microstructure and mechanical properties of the composites was revealed by using the scanning electron microscope (SEM), transmission electron microscopy (TEM) and electronic universal testing machine. The microstructural characterization demonstrated that the boride crystallized into a B27 structure and the α2-precipitated amount increased with the (Ti, Nb)B increasing. When the (Ti, Nb)B content reached 4.9 vol%, both the α2 and reinforcement exhibited a continuous distribution along the prior particle boundaries (PPBs). The tensile test displayed that the tensile strength of the composites presented an increasing trend with the increasing (Ti, Nb)B content followed by a decreasing trend. The composite with a 3.2 vol% reinforcement had the optimal mechanical properties; the yield strengths of the composite at 25 and 650 °C were 998.3 and 774.9 MPa, showing an 11.8% and 9.2% improvement when compared with the Ti2AlNb-based alloy. Overall, (Ti, Nb)B possessed an excellent strengthening effect and inhibited the strength weakening of the PPBs area at high temperatures; the reinforcement content mainly affected the mechanical properties of the (Ti, Nb)B/Ti2AlNb composites by altering the α2-precipitated amount and the morphology of (Ti, Nb)B in the PPBs area. Both the continuous precipitation of the brittle α2 phase and the agglomeration of the (Ti, Nb)B reinforcement dramatically deteriorated the mechanical properties.

Effect of the Processing Routes on the Properties of CoCrFeMnNi Alloy

Abstract High entropy alloys are one of the most developing classes of materials of the 21st century. Their properties can significantly vary depending on their chemical composition and processing method. Thus, the microstructure and mechanical properties of CoCrFeMnNi high entropy alloy prepared by conventional casting, melt-spinning and mechanical alloying were investigated in this study. The observed structure and grain size were typical for this type of alloy and production methods. It was found that the hardness of the sample prepared by mechanical alloying with subsequent spark plasma sintering is higher compared to cast and melt-spun samples due to the finer microstructure and higher deformation energy stored.

Relevance of Solidification Kinetics for Enhanced Thermoelectric Performance in Al-Doped Higher Manganese Silicides.

The solidification kinetics of an alloy from its liquid state forms an underlying basis for microstructural engineering, wherein the state of thermodynamic equilibrium associated with the melt-grown crystal and the quenched amorphous solid denotes the two limits for crystallinity in the alloy synthesis. In this study, we report the implication of the crystalline state on the thermal and electrical transport properties of partially substituted Mn(Si1-xAlx)γ by comparing the single crystals melt-grown by the Bridgman method, and polycrystals synthesized from melt spinning (MS) and subsequent spark plasma sintering (SPS). The rapidly solidified alloys exhibited nanocrystalline microstructures in MS ribbons, while melt-grown single crystals displayed characteristics evolution of MnSi striations with limited solubility of Al. It was observed that Al as a p-type dopant enhances the carrier concentration and electrical conductivity, while nanocrystallinity in MS + SPS polycrystals and secondary phases in monocrystals were effective in enhancing the phonon scattering. Maximum zT values of ∼0.54 (±0.05) at 823 K and 0.75 (±0.05) at 873 K were attained for the single crystal (directed perpendicular to the c-axis) and melt-spun polycrystals (along the in-plane direction), respectively. These results present the efficacy of aliovalent Al substitution and demonstrate the critical role of the solidification kinetics in optimizing the carrier concentration and enhancing the phonon scattering in higher manganese silicide crystals for thermoelectric applications.

Microstructure and strengthening mechanisms of novel lightweight TiAlV0.5CrMo refractory high-entropy alloy fabricated by mechanical alloying and spark plasma sintering

Lightweight TiAlV0.5CrMo refractory high-entropy alloy (RHEA) with ultra-fine grains was initially fabricated by mechanical alloying (MA) and subsequent spark plasma sintering (SPS). The microstructural evolution, mechanical performance and strengthening mechanisms of the alloys in various processing conditions were systematically characterized. A single body-centered cubic (BCC) solid solution phase with nanocrystalline structure was formed after milling for 30 h. Afterward, the BCC2 and Al2O3 phases were precipitated from the supersaturated BCC structure during the sintering process in the temperature range from 1100 to 1300 °C. The specimen with an average grain size of ∼0.47 µm and an precipitation phase of less than ∼0.15 µm was obtained at sintering temperature of 1200 °C, exhibiting ultra-high micro-hardness of 10.26 GPa, acceptable compressive yield strength of 1825 MPa, outstanding ultimate compressive strength of 2989 MPa and satisfactory plastic strain of 17.8% at room temperature. The excellent mechanical properties of the TiAlV0.5CrMo RHEA were dominantly attributed to the combined effects of inherent solid solution strengthening, grain boundary strengthening and precipitation strengthening. It is anticipant that the process of combining MA and SPS is the effective method to produce novel lightweight and refractory structural material with outstanding performance.