To improve the corrosion and wear resistance of high-entropy alloy (HEA) coatings to meet the extreme marine working environment, W was introduced into the FeCoNiCrAl coating system, and FeCoNiCrAl and FeCoNiCrAlW coatings were fabricated by plasma spraying. Microstructure, corrosion behavior, tribocorrosion performance, and interfacial electronic structure were systematically investigated. The results show that the addition of W element significantly improves the comprehensive properties of the coatings. The FeCoNiCrAlW coating achieved a 30.59% increase in hardness, while the coating porosity decreased by 36.25%. Compared with FeCoNiCrAl HEA coatings, the FeCoNiCrAlW HEA coatings exhibit a dramatic reduction in corrosion current density from 1.80 & times; 10-5 A center dot cm-2 to 5.72 & times; 10-7 A center dot cm-2, confirming its superior corrosion resistance. The wear rate is reduced from 4.84 & times; 10-6 mm3 center dot N-1 center dot m-1 to 3.75 & times; 10-6 mm3 center dot N-1 center dot m-1 in 3.5 wt% NaCl solution. FeCoNiCrAlW coating exhibits a lower oxidation tendency after tribocorrosion. W incorporation regulates the electronic structure of the alloy system and reduces interfacial charge transfer, indicating superior interfacial stability, thereby suppresses Cl-induced corrosion and oxidation. These effects inhibit the formation of corrosion products and material spallation, ultimately leading to the improved tribocorrosion resistance of the FeCoNiCrAlW coating.

The ongoing development of maritime powers has driven markedly growing requirements for novel naval and civilian vessel categories in recent years. The import temperature of gas turbines is rising, and the issue of corrosion can no longer be ignored, creating an urgent need to develop coatings with high-temperature resistance, corrosion resistance, and good toughness. This study utilized plasma spraying technology to prepare composite AT13 ceramic coatings with 0 wt.%, 5 wt.%, 10 wt.%, and 15 wt.% GO/Cu (GO:Cu = 1:10) content. It systematically investigated the effects of GO/Cu doping on the porosity, Vickers hardness, fracture toughness, thermal shock resistance, and corrosion resistance of the AT13 coatings while exploring the corrosion behavior of the composite coatings. The experimental results indicate that doping with GO/Cu can effectively fill the pores of the coatings, leading to an overall improvement in coating performance. The coating with 10 wt.% doping (G2) exhibited the best comprehensive performance, with a 72% reduction in porosity compared to the original coating, a 23.2% increase in Vickers hardness, a 31.4% enhancement in fracture toughness, and an 83% decrease in corrosion rate. It also demonstrated the best thermal shock resistance, maintaining a relatively intact surface after 31 days of immersion in artificial seawater, with only a few pitting and cracking defects observed in the areas of corrosion.

This study investigates the optimization of the martensitic transformation and mechanical properties of Ni-Mn-Sn alloys through the co-doping of Cu and graphene oxide. Firstly, the research examines the effect of Cu doping, which significantly enhances the entropy change (Delta Str) during the martensitic transformation. First-principles calculations predict that co-doping with Cu and graphene oxide reduces the martensitic transformation temperature, increases the Curie temperature, and decreases the magnetization difference between austenite and martensite (Delta M). These theoretical predictions are corroborated by experimental results. The impact of graphene oxide doping on the microstructure was analyzed, showing that it induced secondary phase reinforcement and grain refinement. The precipitates in the graphene oxide-doped alloy significantly impeded the martensitic transformation. However, the compressive strength increased from 267 MPa in the undoped state to 1041 MPa, and the fracture strain improved from 3.6 % to 6.84 % at a graphene oxide content of 3 at%. The Ni50(Mn31.9C0.6Cu3.5)Sn14 alloy with minor precipitates along grain boundaries demonstrating a Delta Tad of -4.05 K under a 3 % strain at room temperature. These findings indicate that the synergistic effect of Cu and graphene oxide co-doping offers a promising strategy for developing high-performance elastocaloric materials for solidstate refrigeration applications.

Three-dimension (3D) current collector with interior porous structure and large specific surface area can suppress the volume change of lithium (Li) metal anode and reduce the local current density, which is beneficial for uniform deposition of Li. However, the low Li affinity and instability of Li+ transport allow Li metal to easily deposit on the top of the 3D current collector, accelerating the growth of Li dendrites. Herein, a 3D current collector with a stable Li+ transport channel and a vertical interfacial activity gradient is proposed, realizing a long-life Li metal battery. The density functional theory (DFT) and experimental results demonstrate that the vertically Cu nanoarray has a low Li+ migration barrier, while the ZnO nanocrystalline at the bottom of the 3D current collector has a high Li affinity. The synergistic action of the vertically Cu nanoarray and ZnO nano- crystalline results in the directed Li metal homogeneous deposition. Furthermore, the Li2O artificial protective layer formed by the interaction of ZnO with Li metal also promotes the transport of Li+ into the inner current collector. Hence, the Li directed homogeneous deposition realizes a long cycle life Li metal anode for more than 4000 h of the symmetrical cell at 2.0 mA cm-2 current density and 1.0 mA h cm-2 plating/stripping capacity, as well as more than 500 cycles with 98.8 % coulombic efficiency of the half cell at 1.0 mA cm-2 current density and 1.0 mA h cm- 2 capacity. This work provides a feasible vertical activity gradient directionally guided Li deposition strategy for realizing long cycle life Li metal batteries.

The doping of multilayer graphene (MLG) was investigated in this study to optimize the mechanical properties, elastocaloric effect and cyclic stability of Ni-Co-Mn-Ti alloys. The formation energies of Ni6Co2Mn6Ti2 and Ni6Co2Mn6Ti2C1 alloys were calculated using first-principles methods. It was revealed that the introduction of C(MLG) significantly reduced the formation energy, thereby enhancing the stability of the crystal structure. The microstructure, martensitic transformation, crystal structure, mechanical properties, elastocaloric performance and cyclic stability of MLGx/(Ni36Co14Mn35Ti15)100-x(x = 0, 0.3, 0.6, 0.9, 1.5) alloys were systematically investigated. It was found that the doping of MLG induced the formation of black particulate precipitates within the alloy. These precipitates altered the composition of the alloy matrix and led to an increase in the phase transformation temperature. The incorporation of MLG further facilitated the transition of the alloy's crystal structure from an L2₁ cubic austenite phase to a 10 M martensitic phase. Moreover, both the mechanical strength and the elastocaloric properties were significantly enhanced by MLG doping. The compressive fracture stress and strain were observed to increase progressively with increasing MLG content. Specifically, the MLG1.5/(Ni36Co14Mn35Ti15)98.5 alloy achieved a compressive fracture stress of 1005 MPa and a compressive fracture strain of 10.3

The impact of Gd doping on Ni-Mn-In alloys was investigated using a combination of experimental studies and first-principles calculations. The results of first-principles calculations reveal that Gd doping tends to occupy the sublattices of Ni and In in the Ni8Mn6In2 alloy. Gd substitution of either Ni or In increases the martensitic temperature and decreases the Curie temperature at the same time. In particular， the increase in phase transition temperature is more significant after Gd replaces In. The electron density of states analysis shows that Gd doping decreases the austenite stability and increases the martensite stability， which is the main reason for the increase in phase transition temperature. The Ni50-xMn35In15Gdx（x=0，1，2） and Ni50Mn35In15-xGdx（x=0，1，2） polycrystalline alloys are successfully prepared using a vacuum arc melting furnace， and analyzed by the DSC experimental data， it was observed that the doping of Gd enhances the phase transition temperature of alloy. Specifically， the martensitic transformation starts temperature of Ni50Mn35In13Gd2 reached 160 ℃， which can meet the high-temperature （≈97 ℃） operating conditions. The doping of a single Gd atom does not change the magnetic state of the alloy parent phases and martensitic phases in Ni-Mn-In alloys， resulting in a minor effect on the difference of magnetization. The mechanism of Gd doping affects the magnetic structure of the alloy is elucidated.

The dendrite growth and volume expansion of the Li metal anode, as well as the LiPSs "shuttle effect" and slow conversion kinetics of the S cathode, have severely hampered the large-scale development of LSBs. Herein, a simple hydrothermal method is employed to synthesize rod-like AgVO3, which is then used as the Li metal anode current collector and the separator modification, respectively. As the Li metal anode current collector, AgVO3 has a strong Li affinity, which can lower Li nucleation overpotential and guide uniform deposition of Li metal. The AgVO3-modified separator can accelerate the redox kinetics of LiPSs and achieve the anchoring of LiPSs. The results of DFT calculation and experiments reveal that the AgVO3 enable the Ag horizontal d orbitals (d(xy)/d(x)(-y)(2)(2)) to hybridize with the S p orbital to form additional sigma/sigma* and pi/pi*. The activation of horizontal d orbitals can increase LiPSs anchoring ability, reduce the reaction barrier, and accelerate LiPSs transformation. Hence, the LSBs assembled with the Li@AgVO3 anode and AgVO3 modified separator show excellent cycle performance. This work gives a novel idea for the application of high catalytic performance materials represented by AgVO3, and its unique catalytic performance can successfully achieve LSBs with high performance.

This study systematically investigates the microstructure, martensitic phase transformation, crystal structure, and mechanical properties of (Ni43Mn47Sn9Gd1)100−xBx (x = 0, 0.8, 1.5 and 3 at

The impact of boron microalloying on the performance of NiMnSn shape memory alloys was investigated using a combination of simulation and experimental methods. The simulation results reveal that B atoms tend to occupy the tetrahedral interstitial positions composed of Ni and Mn. Furthermore, the doping of B atoms not only increases the lattice constant and cell volume of the alloys, but also enhances the phase transition temperature and reduces the thermal hysteresis. The doping of B can enhance the phase stability of austenite and reduce total magnetic moments in the Ni–Mn-Sn alloy. Experimental investigations were conducted on (Ni43Mn47Sn10)100-XBX (X=0,1.5,3) alloys, and findings corroborate the simulations, confirming that B element doping elevates the phase transition temperature, lattice constant, and cell volume, while diminishing the thermal hysteresis. Furthermore, boron microalloying contributes to improved mechanical properties. At a B doping level of 3%at, the annealed alloy compressive strength increases by 125%, reaching 578MPa, with a fracture strain of 6.7%. However the mechanical properties of the as-cast alloy surpass those of the annealed state, with the compressive strength of the same-component cast alloy reaching 1080MPa, and a fracture strain of 7.9%, marking an 87% improvement over the annealed state.

In this paper, we focus on the optimized process parameters of the TiNiTa shape memory alloy functional coatings prepared by laser cladding technology on the Ti6Al4V (TC4) alloy, and studied properties. On the basis of orthogonal experiment, the optimum process parameters of TiNiTa coatings were determined as follows: the laser power was 100 W, the scanning rate was 2.5 mm/s, the defocusing amount was 10 mm, the pulse width was 5 ms, and the frequency was 10 Hz. The influence of laser power, scanning speed and defocus amount on the hardness of cladding layer was evaluated by the range analysis from the experimental data. The results show that the range of defocusing amount, scanning speed and laser power were R1 = 34, R2 = 14.334, R3 = 44.334, respectively. Therefore, the degree of influence on the process parameters on the quality of the prepared TiNiTa coating was determined in the following order: defocus amount, laser power, scanning speed. When the energy density was 1698 J/mm2, the microstructure of the cladding layer was compact and fine, and the metallurgical bond with the matrix was formed. In addition, the polarization potential and the electrochemical impedance spectrum (EIS) radius of the cladding layer were firstly increased and then reduced with the increase of the energy density. It can be seen that the corrosion resistance of TC4 titanium alloy surface was significantly improved. XRD results shows that the cladding layer was mainly composed of B2 parent phase, B19′ martensite phase and Ti2Ni phase. The results indicate that energy density was an important factor affecting the structure and properties of cladding layers. Through the above analysis, the combination of orthogonal test and range analysis provides an efficient and reliable method to select and optimize the technological parameters of laser cladding.

Effect of Ta-alloying on microstructure, martensitic transformation and mechanical property of Ni53.5Mn25-Ga21Ta0.5 alloy systematically investigated. The results show that the morphology of substructure of Ni-Mn-Ga alloy significantly changed, which the converted from plate martensite to the lath martensite. The compres-sion tests show that a compressive strength of 1380 MPa with a fracture strain achieved up to 21.92 % in the Ni53.5Mn25Ga21Ta0.5 alloy at room temperature. At the same time, the martensite unchanged with T-type non -modulated structure. In addition, the martensitic transition temperature obviously decreased from 350 degrees C to 208 degrees Cand hysteresis temperature increased about 20 degrees Cwhen Ta substituted of Ni.

The TiNiTa shape memory coating was prepared on the surface of TC4 by laser cladding technology, and the microstructure, wear resistance and microhardness of the TiNiTa coating were studied by optical microscope, X-ray diffractometer, scanning electron microscope, microhardness tester, friction and wear testing machine. The results show that the increased energy density, the dilution rate of the sample gradually increased. At same time, When the laser cladding process parameters were changed, the maximum microhardness of the TiNiTa cladding layer was HV867.4, which was about twice that of the matrix. In addition, the significantly increased wear resistance of TC4 alloy by laser cladding technology. Under the same conditions, the friction coefficient of TiNiTa cladding layer fluctuates less than that of matrix. The wear loss of TiNiTa cladding layer was only 1/8 of that of matrix. Finally, by calculating the wear volume, it was found that the wear resistance of the cladding layer was 42 times higher than that of the matrix, and the wear mechanism was adhesive wear. Through orthogonal test analysis, it is obtained that the sequence of influence of each process parameter on coating quality was as follows: spot diameter > laser power > scanning speed. The coating and the substrate form a metallurgical bond. The TiNiTa coating mainly contains dendrites, equiaxed crystals and columnar crystals, and the structure is compact and small.

Mechanical properties and elastocaloric effect are the most important parameters of Ni-Mn-In shape memory alloys in the refrigeration field. This paper mainly studies the influence of Ag doping and different preparation methods on the mechanical properties and elastocaloric effect of the alloys. The doping of Ag element not only increases the martensitic transformation temperatures and reduces the critical phase transformation stress, but also improves the mechanical properties and elastocaloric effect of the alloys. The adiabatic temperature change (Delta Tad) of Ni50Mn34In15.5Ag0.5 prepared by arc melting was - 7 K at 4% strain, and the alloy fractured after 69 cycles with 3% strain. Furthermore, Ni50Mn34In15.5Ag0.5 powders prepared by gas-atomization were used by SPS sintered to obtain 10 mu m grains alloys. This preparation method enables the fracture stress and fracture strain to reach 1625.8 MPa and 17.1%, respectively. At the same time it remains stable after 300 cycles with 6.5% strain, indicating the significant improvement of mechanical properties and cyclic stability in Ni-Mn-In metamagnetic shape memory alloy. (c) 2023 Elsevier B.V. All rights reserved.

The effect of Al doping on microstructure, crystal structure, martensitic transformation, mechanical properties and corrosion resistance of Ni48Co1Mn37In14-xAlx (0 <= x <= 2) magnetic shape memory alloys was studied by the material preparation method of arc melting. The results show that the grain size of the alloy is reduced by replacing part of In with Al, and the average grain size is reduced to about 10 mu m when 2at% Al element is doped, which is about 1/35 of that of the undoped sample. When the doping amount of Al is 0.25at%.2at%, the metal Al is completely dissolved into the matrix, and the solid solubility of Al in the alloy increases with the increase in the doping amount; when the doping amount is 2at%, the solid solubility of Al in the matrix is close to 2at%. With the substitution of Al for In, the alloy changes from the two-phase structure of L2(1) cubic austenite and monoclinic 6M martensite to a single 6M at room temperature, the unit cell volume gradually decreases, and the martensitic transformation temperature shows an upward trend. The compressive strength of the alloy continues to increase, and compared with that of Ni48Co1Mn37In14, the compressive fracture strength of Ni48Co1Mn37In12Al2 is increased by 160%, and the compressive strain also increases from 5.46% to 6.36%. After an appropriate amount of Al replacing In, the corrosion resistance of the alloy in artificial seawater generally shows an increasing trend. The corrosion resistance of Ni48Co1Mn37In12Al2 alloy is significantly higher than that of Ni48Co1Mn37In14 alloy, and its corrosion resistance is close to that of 304 stainless steel.

基于磁热效应的新型固体磁制冷技术因具有节能高效、稳定可靠的优点而备受关注,该技术利用磁性材料在磁相变过程中与外界环境之间的热交换作用而产生制冷效果.Ni-Mn-In基磁制冷合金在磁场诱导下可以产生逆磁热效应,具有较大的磁熵变.介绍了Ni-Mn-In基磁制冷合金的晶体结构和相变行为,重点综述了晶粒尺寸、化学成分、热处理工艺等因素对Ni-Mn-In基磁制冷合金磁热效应的影响,以及通过微合金化提高合金力学性能的研究进展.对未来该系列合金的研究方向进行了展望.

采用电弧炉熔炼法制备了Ni45Co5Mn37.5?xIn12.5Crx合金铸锭,研究了用Cr部分替代Mn对Ni45Co5Mn37.5In12.5磁性形状记忆合金的显微组织、马氏体相变、力学性能的影响.结果表明,由于价电子浓度的减小,Cr替代Mn使得马氏体相变温度明显降低,随着Cr替代量增大,马氏体结构从单斜14M结构转变为10M结构,在Cr替代量较高的合金中观察到颗粒状和长条状富Cr析出物.替代量x=3的样品,其颗粒状和长条状析出物在合金内部均匀分布,未掺杂合金的抗压强度为130 MPa,而x=3的合金抗压强度达到了881 MPa,压缩实验表明掺杂Cr元素能显著提高Ni-Co-Mn-In合金的力学性能.

The microstructure, martensitic transformation, mechanical properties and corrosion resistance of Ni45Co5Mn38Sn12-xGdx (x = 0.3, 0.6, 1, 1.5at%) magnetic shape memory alloy have been systematically investigated. When the Gd doping amount is 0.3 at%, some gray mottled phases appear in the alloy matrix, and there are white particle phases around the gray speckle phases. As Gd doping content continues to increase, the gray mottled phases and white particle phases gradually join together distributing along the grain boundaries. These alloys present 10M orthorhombic martensite at room temperature. Both 10M orthorhombic martensite and 14M monoclinic martensite exist Ni45Co5Mn38Sn10.5Gd1.5 alloy. The valence electron concentration increases and the phase transition temperature increases as a result of Gd doping. The compressive strength and strain of the alloy are significantly enhanced by the incorporation of Gd. When the Gd content is 1.5 at %, the compressive strength of the alloy is up to 1258 MPa and the compressive strain reaches to 13.72%. The doping of Gd enhances the seawater corrosion resistance of NiCoMnSn alloy. Moreover, NiCoMnSnGd alloys have better seawater corrosion resistance than 304 stainless steel.

A simple synthesis has been proposed for seaweed-like amorphous TiO(2-x )modified Sb (a-TiO2-x/Sb) composite nanowires as sodium-ion battery (SIBs) anodes by a dealloying method of Al-Sb-Ti alloys. Compared with other conventional methods, this method has the advantages of simple preparation, high yield and easy large-scale synthesis. It is excitingly discovered that a-TiO2-x/Sb effectively alleviates volume changes and stabilizes the solid electrolyte interface (SEI). The a-TiO2-x/Sb nanowires electrodes deliver outstanding electrochemical performance based on the synergistic effects, exhibiting a high reversible capacity of 591.9 mA h g(-1) at 100 mA stable cycling performance with a high capacity retention of 96.4% after 200 cycles and superior rate capability 382.2 mA h g(-1) at 10,000 mA g(-1), which is very competitive among the reported Sb-based anodes.

The effects of different forming process on the microstructure, martensitic transformation, and mechanical properties of the Ni 50 Mn 34 In 14 Co 2 (numbers indicate at.%) alloys were investigated in detail. The results show that the microstructure of Ni 50 Mn 34 In 14 Co 2 alloy consists of the matrix and the second phase by powder hot forging technology under the forces in different directions and spark plasma sintering (SPS), and the prepared sample has obvious preferred orientation by applied force in the three directions. The grain and the second phase of prepared sample were obviously refined by the hot forging technology. The martensitic transformation behavior was almost unchanged by different forming process. In addition, the shape memory effect of prepared Ni 50 Mn 34 In 14 Co 2 alloy was significantly enhanced by different forming processes.