Solid Atoms Research Articles

Experimental and molecular simulation study of CO2 adsorption in ZIF-8: Atomic heat contributions and mechanism

We successfully synthesised ZIF-8 using the solvothermal method at room temperature to study CO2 adsorption storage at 273 and 298 K up to 35 bar. Characterisation methods such as BET, SEM-EDS, XRD, and TGA were used to measure the physical and composition properties of ZIF-8. Grand canonical Monte Carlo (GCMC) simulation was conducted to compare with experimental data and get inside of the CO2 adsorption mechanism by calculating the isosteric heat and its fluid–fluid and solid–fluid contributions. The second was also split into fluid–solid atom contributions to understand in detail the interaction between CO2 and ZIF-8. The analyses revealed that there are three main stages during the CO2 adsorption gas–solid atom contributions, developing, pore-filling and densification. During the developing and pore-filling stages the largest fluid–solid atom contribution to the isosteric heat is CO2-C2 interactions, indicating that the CO2 is adsorbed close to the hexagonal windows of the ZIF-8 structure, while during the densification stage the largest contribution is CO2-N interactions. Where C2 and N refers to C-atom and N-atom, respectively in NCH group of the solid framework. This is because CO2 changes its orientation to be able to accommodate more molecules in the pore cavity. This work provides a better understanding of the adsorption mechanism of CO2 on ZIF-8 and shows how molecular simulation can be used to improve the understanding gas adsorption storage on metal–organic frameworks.

Wire-based friction stir additive manufacturing towards isotropic high-strength-ductility Al-Mg alloys

ABSTRACT The formation of eutectic Al-Mg2Al3 phases along the grain boundaries makes it difficult to improve the mechanical properties of high-magnesium-content aluminum alloys. Here, wire-based friction stir additive manufacturing(W-FSAM) was proposed as a novel solid-state additive manufacturing technology. The shearing, transport, and thermo-plasticisation processes of the deposited materials were achieved by a rotational tool and a stationary barrel. The original Mg2Al3 phases were refined and dissolved into the matrix and formed supersaturated solid solution structures. The refined grains with a diameter of 1.27 ± 0.64 μm were achieved through the dynamic recrystallization process. The components achieved isotropic mechanical properties due to the homogeneous equiaxed fine-grain structure. The ultimate tensile strength reached 415 ± 11 MPa with an elongation of 31.0 ± 2.0%, superior to the commercial 5xxx products. The enhanced strain hardening capacity was achieved by the suppressed emission of dislocations from grain boundaries and the interaction between the supersaturated solid solute atoms and mobile dislocation.

Quantum Chemical Model Calculations of Adhesion and Dissociation between Epoxy Resin and Si-Containing Molecules

There is no doubt that when solid surfaces are modified, the functional groups and atoms directly bonded to solid atoms play a major role in adsorption interactions with molecules or resins. In this study, the adhesion and dissociation between epoxy resin and molecules containing Si atoms were analyzed. The analysis, conducted in contact with the solid surface of silicon, utilized quantum chemical calculations based on a molecular model. We compared some Si-containing molecular models to test quantum chemical calculations that contribute to the study of adhesion and dissociation between epoxy resins and solid surfaces somehow other than simple potential energy curve calculations. The AFIR (artificial force induced reaction) method, implemented in the GRRM (global reaction route mapping) program, was employed to separate an epoxy resin model molecule and three types of silicon compounds (Si(CH3)2(OH)2, Si(CH3)4, and (CH3)2SiF2) in three directions, determining their minimum dissociation energy when changing the applied energy by 2.5 kJ/mol. In systems with weak hydrogen bonds, such as Si(CH3)4 or (CH3)2SiF2, the energy required for dissociation was not large; however, in systems with strong hydrogen bonds, such as Si(CH3)2(OH)2, dissociation was more difficult in the vertical direction. Although anisotropy due to hydroxyl groups was calculated in the horizontal direction, dissociation remained relatively easy.

Designing a new ultra-high strength steel with multicomponent precipitates under material genetic design

Ultra-high strength steels with excellent strength, ductility and toughness have become one of indispensable high-performance structural materials. The development of ultra-high strength steels with higher performance has been widely concerned to break the strength-ductility trade-off. This study proposes a material inverse design strategy that combines material genetic design with thermodynamic calculation to search for new alloys with desirable microstructure and optimal strengthening contributions. Based on the advancement of the 'Pareto Front', a new steel with superior properties was successfully screened from 390,625 candidate individuals, which was verified by experiments. The experimental results show that a new steel Fe-0.25C-14.8Ni-17.0Co-2.54Mo-1.56Cr-0.53Al-1.06Cu-0.38V (wt. %) has been successfully developed. After quenching-cryogenic-aging process, the new steel achieved a superior combination of strength, ductility and toughness, with a yield strength of 2.2 GPa, an elongation-to-failure of 10% and a V-notch impact energy of 15 J. Multi-scale microstructure characterization indicates that such superior property synergy arises from the unique microstructure: lath martensite matrix with high-density dislocations and interstitial solid soluble carbon atoms, embedded fine M2C, NiAl and Cu-rich nanoprecipitates. We present an in-depth discussion on the origins of superior strength/ductility/toughness combinations of the new steel to validate the design strategy and provide an accessible pathway exploiting high-performance ultra-high strength steels.

Local-time formula for dissipation in solid ionic electrolytes

When ions move through solids, they interact with the solid's constituent atoms and cause them to vibrate around their equilibrium points. This vibration, in turn, modifies the potential landscape through which the mobile ions travel. Because the present-time potential depends on past interactions, the coupling is inherently nonlocal in time, making its numerical and analytical treatment challenging. For sufficiently slow-moving ions, we linearize the phonon spectrum to show that these nonlocal effects can be ignored, giving rise to a draglike force. Unlike the more familiar drag coefficient in liquids, the drag takes on a matrix form due to the crystalline structure of the framework. We numerically simulate trajectories and dissipation rates using both the time-local and nonlocal formulas to validate our simplification. The time-local formula dramatically reduces the computational cost of calculating the motion of a mobile particle through a crystalline framework and clearly connects the properties of the material to the drag experienced by the particle. Published by the American Physical Society 2024

Study of Crystallography and Reciprocal Space of Higher Oxides of Lanthanides Using Electron and Neutron Diffraction

Abstract: This study explains uses electron and neutron diffraction techniques to study the crystallography and reciprocal space of higher oxides of lanthanides. The significance of crystallography in comprehending the geometric configuration and bonding of atoms in solids is discussed at the outset of the study. The comprehensive analysis of the crystal structures using accelerated electrons and neutrons highlights the tremendous penetration power of these particles. While neutron diffraction is concerned with plane incidence waves and their scattered counterparts, electron diffraction is concerned with electron generation pulsed by a laser.Important findings show how experimental data may be used to validate Bragg's equation and show how scattering angles, interplanar distance, and order of wavelength are related. To display the relationship between electron energy and electron radiation per electron volt, energy distribution curves are displayed. Additionally, several crystal systems, such as hexagonal, monoclinic, and cubic face-centered structures, are revealed by structural investigation of higher oxides of lanthanides, such as terbium dioxide (Tb2O3).The talk emphasizes how, in contrast to other elements in the series, lanthanides have special qualities that enable them to produce higher oxides with oxidation states greater than +3. The outcomes highlights the improved precision and in-depth structural insights that come from combining electron and neutron diffraction methods. This opens the door for more studies in the crystallography of complicated materials in the future.

Ferritic–Martensitic Steels in Power Industry: Microstructure, Degradation Mechanism, and Strengthening Methods

Ferritic–martensitic (F–M) steels are widely used for high‐temperature pressure vessels and reactor cladding structures in power plants. The high operating temperatures and pressures, as well as the radiation environment, significantly challenge the mechanical stability of these steels. Here, the degradation mechanisms in F–M steels during creep and thermal aging under these harsh environments are reviewed. The exceptional mechanical properties of F–M steels are mainly attributed to their well‐constructed microstructures and chemical compositions. Microstructural barriers such as dislocations, solid solution atoms, and precipitates play key roles in resisting degradation. During the long‐term service, the microstructures undergo gradual evolution, resulting in a deterioration of mechanical properties at the macrolevel. In addition to the degradation mechanisms, some recent advancements in strengthening methods, including microalloying strengthening, thermomechanical treatment (TMT), and oxide dispersion strengthening, are summarized, aimed at the development of next‐generation F–M steels. The strengthening of the F–M steels is mainly achieved by enhancing the thermal stability of their microstructures. Insight into both the deterioration mechanisms and strengthening methods of F–M steels may pave the way for new approaches in developing high‐performance steels for applications in next‐generation power plants operating at ultrahigh operating temperatures and pressures.

Molecular dynamics study of high temperature Ag-Cu-Sn liquid metal infiltration between Ag-Cu alloys：Influences of adsorption and dissolution

Infiltration is the basic process underlying solder connections between alloys. In this study, molecular dynamics simulation was used to systematically investigate the infiltration process of Ag-Cu-Sn liquid metal between multi-formulations Ag-Cu alloys, along with the kinetic factors of the solid/liquid interface formation process. It was found that the infiltration velocity on the surface of the Cu-rich alloys is higher than that on the Ag-rich alloy surface. The difference in velocities originates from both adsorption and dissolution. The competitive interplay between these two factors directly impacts the bonding between solid and liquid atoms, consequently changing the ability of the interface to constrain the movement of liquid atoms. Analysis based on MKT suggests that infiltration along the three-phase line is primarily governed by molecular friction, whereas on the Ag90Cu10 surface, it is driven by the growth of adsorbed products. Additionally, the influence of solid/liquid interactions on wettability was also discussed.

Effect of Dynamical Motion in ab Initio Calculations of Solid-State Nuclear Magnetic and Nuclear Quadrupole Resonance Spectra.

Solid-state nuclear magnetic resonance (SSNMR) and nuclear quadrupole resonance (NQR) spectra provide detailed information about the electronic and atomic structure of solids. Modern ab initio methods such as density functional theory (DFT) can be used to calculate NMR and NQR spectra from first-principles, providing a meaningful avenue to connect theory and experiment. Prediction of SSNMR and NQR spectra from DFT relies on accurate calculation of the electric field gradient (EFG) tensor associated with the potential of electrons at the nuclear centers. While static calculations of EFGs are commonly seen in the literature, the effects of dynamical motion of atoms in molecules and solids have been less explored. In this study, we develop a method to calculate EFGs of solids while taking into account the dynamics of atoms through DFT-based molecular dynamics simulations. The method we develop is general, in the sense that it can be applied to any material at any desired temperature and pressure. Here, we focus on application of the method to NaNO2 and study in detail the EFGs of 14N, 17O, and 23Na. We find in the cases of 14N and 17O that the dynamical motion of the atoms can be used to calculate mean EFGs that are in closer agreement with experiments than those of static calculations. For 23Na, we find a complex behavior of the EFGs when atomic motion is incorporated that is not at all captured in static calculations. In particular, we find a distribution of EFGs that is influenced strongly by the local (changing) bond environment, with a pattern that reflects the coordination structure of 23Na. We expect the methodology developed here to provide a path forward for understanding materials in which static EFG calculations do not align with experiments.

Nature of the bond in intermetallic compounds

By studying 398 binary compounds crystallizing in five different crystal structures, it is shown that atomic radii of the elements RA and RB change to reach a constant radius ratio rA/rB(≡ϒ) in a cubic system. In systems of lower symmetry, a range of ϒ values, each corresponding to a certain axial ratio, is possible. Accurate charge values on atoms in solids are derived from the experimental internal radii rA and rB, using Shannon’s compilation of radii versus charge states for elements. It is found, for the first time, that charge transfer and radii change reverse their direction at the ϒ point. Electronegativity difference relative to its value at the ϒ point is recognized to correctly predict the charge transfer and radii changes with RA/RB. The deduced electronic structure of solids, based on spherical ions carrying partial charges, confirms that the metallic atom-pair bond is a resonating polar covalent bond. Identification of the number of electrons that contribute to cohesion and electrical conduction individually, allows successful prediction of electrical conductivity variation for transition metals and p-elements in the periodic table. From a knowledge of accurate valence of elements and of charge on the atoms, variation in the 197Au isomer shift of the gold compounds of CsCl type structure is predicted. The charges on atoms computed using the Quantum Theory of Atoms in Molecules (QTAIM) technique agree with those obtained in our work for compounds belonging to two of the structure types. For compounds belonging to the other three, the charge values obtained by the two methods do not agree. The disagreement correlates to not reckoning the role of the ϒ point. The effect of ϒ point is so fundamental and universal that most physical properties obtained by the secondary processing of primary DFT data, can be influenced by it.

Cavity-enhanced single artificial atoms in silicon

Artificial atoms in solids are leading candidates for quantum networks, scalable quantum computing, and sensing, as they combine long-lived spins with mobile photonic qubits. Recently, silicon has emerged as a promising host material where artificial atoms with long spin coherence times and emission into the telecommunications band can be controllably fabricated. This field leverages the maturity of silicon photonics to embed artificial atoms into the world’s most advanced microelectronics and photonics platform. However, a current bottleneck is the naturally weak emission rate of these atoms, which can be addressed by coupling to an optical cavity. Here, we demonstrate cavity-enhanced single artificial atoms in silicon (G-centers) at telecommunication wavelengths. Our results show enhancement of their zero phonon line intensities along with highly pure single-photon emission, while their lifetime remains statistically unchanged. We suggest the possibility of two different existing types of G-centers, shedding new light on the properties of silicon emitters.

Thermal Transport across Liquid–Solid Interface with a Single-Atomic Structure Based on the Radial Density Depletion Length at a Surface Solid Atom

Thermal Transport across Liquid–Solid Interface with a Single-Atomic Structure Based on the Radial Density Depletion Length at a Surface Solid Atom

Superior strength and electrical conductivity synergy of cold‐drawn Al‐Mg‐Si‐Ce‐Cu wires produced by continuous casting and rolling

Al‐Mg‐Si aluminum wires for overhead power transmission have extensive applications in industry and daily life. In this study, superior strength and electrical conductivity combination in the aged cold‐drawn Al‐Mg‐Si‐Ce‐Cu wires fabricated by continuous casting and rolling are achieved. The cold‐drawn wires exhibit high strength and electrical conductivity combinations of 383±2 MPa, 51.16±0.23% IACS; 373±3 MPa, 51.98±0.25% and 357±3 MPa, 53.16±0.11% IACS, respectively, when aged at 160 °C, 170 °C or 180 °C for 24 h. Subgrain boundaries are introduced into alloys by continuous casting and rolling and cold drawing, causing significant lattice distortion within the grains and providing sites for the nucleation of precipitates. Moreover, HADDF‐STEM (high‐angle annular dark‐field scanning transmission electron microscopy) and DFT (density functional theory) results show that Ce atoms could enter the lattice of β” and replace the Si3 sites, which is energetically preferred. The underlying mechanisms for achieving superior strength‐electrical conductivity combination are to introduce subgrain boundaries via continuous casting and rolling and cold drawing for promoting the transformation of solid solution atoms to finely dispersed precipitates, which significantly reduces the scattering of electrons and hence improves the electrical conductivity. This work provides a new strategy for designing high‐strength and high‐conductivity aluminum alloy wire conductors.This article is protected by copyright. All rights reserved.

Integrately design hybrid lithium-air battery based on the nasicon solid electrolyte and zinc single atoms electrochemical catalysts

The instability of lithium metal and insoluble discharging products, [Formula: see text], has been a formidable challenge that hinders the widespread implementation of lithium-air batteries (LABs). Hybrid electrolyte-based LABs have been proposed as one of the most promising strategies to solve these issues. However, the complex device designs together with a suitable solid electrolyte membrane is one of the key parameters that determine the battery run. Herein, we present a novel approach featuring a three-phase “organic-solid-aqueous” hybrid electrolyte for LABs, incorporating a NASICON-based solid electrolyte and zinc single atoms catalysts. It is clarified that [Formula: see text] (LATP) shows much-enhanced stability compared with the pulverization of [Formula: see text] (LAGP) by the reduction of Ge upon the [Formula: see text] transport across. Combined with the bifunction of Zn SAs/CNF catalysts in ORR/OER, the 4[Formula: see text] pathway has been proven to be established as a primary contributor to the battery’s high efficiency, which can well run over 100 h in the ambient air at room temperature. These innovative methodologies and insights hold promise for advancing the practical application of safe LABs and may extend to various air battery technologies.

Effect of Hf addition on structural transformation and aging stability of Cu–15Ni–8Sn alloy

The Cu–15Ni–8Sn-xHf (wt.%, x = 0–0.6) alloys were prepared by vacuum melting, and the effect of Hf on the micro-structure of as-cast, as-solution-treated and as-aged alloys was systematically investigated, as well as the alloy aging stability. The Hf addition provided a significant role on refining the solidification structure and reducing the micro-segregation degree, and it also made γ-D03 phases more likely to form in needlelike-shape rather than lamellar-shape. With the presence of more Hf atoms, their existence form was accordingly changed from solid solute atoms to nano-scale precipitation phases and then to micron-scale segregation phase. A small content of Hf (0.1 wt%) could effectively improve the aging stability by inhibiting the growth of γ-D03. Once its content reached or exceeded 0.3 wt%, the harmful discontinuous precipitation was completely inhibited, and the common lamellar-shape γ-D03 locating around the grain boundary was no longer formed. Even the alloy failed at higher temperatures, it could only be carried out through the continuous precipitation method, namely the generation of needlelike-shape γ-D03 uniformly in the matrix. The appropriate Hf addition was capable of extending the alloy aging window, and the hardness of Cu–15Ni–8Sn-0.3Hf alloy could still exceed 360 HV even after 48 h aging.

Drone-mounted remote-controlled arm for monitoring and precision spraying coconut rhinoceros beetle infestations

This paper presents a low-cost (locally-assembled) drone system with a sprayer arm and a remote control for monitoring and precisely applying pesticides to coconut trees infested by the Rhinoceros Beetle. A modified RGB IP camera continuously monitors potential coconut beetle infestation points, capturing real-time spray images, and displaying the results through a smartphone interface. The system provides real-time monitoring, allowing immediate remote control of the spray operation from the ground upon detecting beetle infestations. The drone-mounted sprayer arm is controlled in response to the ground-based signals, to accurately extend or contract while effectively dispensing spray chemicals onto the target areas at the upper canopy of coconut trees. In our tests using Nam-Hom coconut trees, which averaged a height of 10.4 m, the system operated at a speed of 1.25 km/h, achieving a spraying flow rate of 0.333 l/h and a working capacity of 0.352 ha/h. The controlled spraying setup emits a solid jet, ensuring precision and effective atomization of chemicals within a distance range of 1.0 to 4.0 m from the target. The spray quality attributes (droplet size, pattern, and coverage) were not significantly affected by the wind speed. The system could potentially reduce labor costs, chemical usage, and health risks associated with pesticide application.

High-temperature corrosion behavior of the FeCrAl laser cladding coatings in waste-to-energy superheaters: Influence of Al content

Enhancing the high-temperature corrosion resistance of superheaters in waste-to-energy plants (WTE) is key to improving the efficiency of WTE power generation. The present study employed laser cladding technology to fabricate Fe-13Cr-xAl coatings, and characterized the microstructure, phase structure, and Vickers hardness of the coatings using OM, SEM, XRD, and a Vickers hardness tester. The study investigated the influence of high-temperature corrosion resistance of the coatings under simulated WTE flue gas conditions. This study found that: Al and Cr both exist in the form of solid solution atoms in the laser cladding coatings. The Vickers hardness of the coatings gradually increased with increasing Al content. When the Al content exceeds 10 %, cracks begin to appear in the coatings, and the number and size of cracks increase with increasing Al content. The Fe-13Cr-7Al coatings exhibit the best high-temperature corrosion resistance under simulated WTE flue gas conditions, and it can achieve ∼73 % of the high-temperature corrosion resistance of the Inconel 625 alloy laser cladding coatings. During high-temperature corrosion, phase separation occurs near the grain boundaries, resulting in chromium depletion zones, which promote intergranular corrosion of the coatings. During the process of high temperature corrosion, the reactions between Al, Cl, and S exhibit the lowest Gibbs free energy. The continuous consumption of Al effectively protects the Fe and Cr in the substrate. Additionally, the formation of aluminum oxide in the coating hinders the inward diffusion of Cl2, thereby beneficially impeding the progress of corrosion. Excessive Al contents in the coatings introduced cracks that served as channels for molten salt to penetrate the matrix, thereby reducing the high-temperature corrosion resistance of the coatings.

Excellent strength-toughness combination of NiAl–30Cr composites with novel in situ composite microstructure containing NiAl matrix and Cr single-phase

Lightweight NiAl alloys are expected to replace high-density nickel-based superalloys, but their mechanical performance needs to be improved. In this work, NiAl–30Cr composites with a novel heterogeneous microstructure composed of fine NiAl matrix and Cr single-phase was successfully prepared. Nanoscale Cr particles with 15 nm in size precipitated in NiAl matrix are coherent with NiAl matrix owing to very low interplanar and interatomic spacing mismatch. Such a composite microstructure makes NiAl–30Cr exhibit high strength and high toughness. The yield strength (1207 MPa), ultimate compressive strength (2307 MPa), product of strength and plasticity (29.3 GPa%), and fracture toughness (10.76 MPa m1/2) of NiAl–30Cr increased by 96.6%, 85.6%, 55.1% and 19.7% respectively at room temperature compared to the corresponding ones of NiAl. At 1000 °C, the yield strength (144 MPa) of NiAl–30Cr was 85.9% higher than that of NiAl. Solution strengthening and precipitation strengthening were the key strengthening mechanisms at room temperature. The enhancement in toughness was attributed to grain refinement, increased crack propagation paths, weakened Ni–Al covalent bonding and coordinated deformation of Cr single-phase and NiAl matrix. By contrast, the main strengthening mechanism at 1000 °C is the solid solution Cr atoms hindering dislocation climbing and the stable interface bonding between the Cr nanoprecipitation phase and the NiAl matrix. This work provides new ideas for preparing high-strength and tough NiAl alloy.

Superior specific capacity and energy density simultaneously achieved by Sr/In co-deposition behavior of Mg-Sr-In ternary alloys as anodes for Mg-Air cells

In this work, the combined addition of strontium/indium (Sr/In) to the magnesium anode for Mg-Air Cells is investigated to improve discharge performance by modifying the anode/electrolyte interface. Indium exists as solid solution atoms in the α-Mg matrix without its second-phase generation, and at the same time facilitates grain refinement, dendritic segregation and Mg17Sr2-phases precipitation. During discharge operation, Sr modifies the film composition via its compounds and promoted the redeposition of In at the substrate/film interface; their co-deposition behavior on the anodic reaction surface enhances anode reaction kinetics, suppresses the negative difference effect (NDE) and mitigates the “chunk effect” (CE), which is contributed to uniform dissolution and low self-corrosion hydrogen evolution rate (HER). Therefore, Mg-Sr-xIn alloy anodes show excellent discharge performance, e.g., 0.5Sr-1.0In shows an average discharge voltage of 1.4234 V and a specific energy density of 1990.71 Wh kg−1 at 10 mA cm−2. Furthermore, the decisive factor (CE and self-discharge HE) for anodic efficiency are quantitively analyzed, the self-discharge is the main factor of cell efficiency loss. Surprisingly, all Mg-Sr-xIn anodes show anodic efficiency greater than 60% at high current density (≥10 mA cm−2), making them excellent candidate anodes for Mg-Air cells at high-power output.

Effects of heat treatment cooling methods on precipitated phase and mechanical properties of CoCrFeMnNi–Mo5C0.5 high entropy alloy

C and Mo in the form of solid solution atom or compound phase is distributed in CoCrFeMnNi high entropy alloy (HEA), which have the effects of solution strengthening or second phase strengthening. CoCrFeMnNi–Mo5C0.5 HEA were prepared by adding C and Mo elements to CoCrFeMnNi HEA, and then which heat treatment were carried out by furnace-cooling, air-cooling and water-cooling respectively. the microstructure and phase composition of as-cast or heat treated CoCrFeMnNi–Mo5C0.5 HEA were examined by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD), the mechanical properties of as-cast or heat treated CoCrFeMnNi–Mo5C0.5 HEA were tested by the tensile test and hardness test, and the effects of heat treatment cooling methods on precipitated second phase and mechanical properties of CoCrFeMnNi–Mo5C0.5 HEA were investigated. The results show that precipitated second phase in CoCrFeMnNi–Mo5C0.5 HEA is MC phase, which is rich in Mo, Cr and C elements. With change of heat treatment cooling methods from furnace-cooling, air-cooling to water-cooling respectively, heat treatment cooling rate is increased. With increase of heat treatment cooling rate, the amount and size of precipitated second phase are all decreases, and the position of second phase precipitation changes from grain boundaries to intragranular. The tensile strength and elongation of heat treatment water-cooled CoCrFeMnNi–Mo5C0.5 HEA are 739 MPa and 41% respectively, which are realizes the simultaneous increased of strength and plasticity. With increase of heat treatment cooling rate, the hardness of CoCrFeMnNi–Mo5C0.5 HEA decreases, the uniform plastic deformation and the elongation are all increases, and the plasticity increase. The fractures of as-cast, heat treatment furnace-cooled, air-cooled and water-cooled CoCrFeMnNi–Mo5C0.5 HEA are all brittle fracture with cleavage characteristics, and the plastic deformation occurs mainly in the uniform plastic deformation stage. The fracture mode of as-cast CoCrFeMnNi–Mo5C0.5 HEA is intergranular fracture, the fracture mode of heat treatment furnace-cooled, air-cooled and water-cooled CoCrFeMnNi–Mo5C0.5 HEA are all transgranular fracture.