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Mechanosensitive amino acid exporters have drawn increasing attention due to their important roles in extracellular accumulation of the target amino acids. Protein engineering is a powerful approach to tailor the properties of amino acid exporters and illustrate structure-function relationships. Here we report the first protein engineering effort on the mechanosensitive glutamate exporter MscCG2 from

The rapid development of aerospace, automotive, and energy exploration industries urgently requires high-temperature shape memory alloys (HTSMAs) which are utilized as compact solid-state actuators, sensors, and energy conversion devices at elevated temperatures. However, the currently prevailing Ni-Ti-X (X = Pd, Pt, and Hf) HTSMAs are very expensive owing to the high cost of Pd, Pt, and Hf elements, which greatly limits their widespread applications. Here, we have developed an inexpensive (Ni50Mn35.5Ti14.5)99.8B0.2 bulk polycrystalline HTSMA with extraordinary high-temperature superelasticity and a giant two-way shape memory effect (TWSME). This alloy exhibits perfect superelasticity with a fully recoverable strain of as high as 7.1% over a wide temperature range from 150 to 280 °C. Furthermore, it shows a giant TWSME with a remarkably high recoverable strain of 6.0%. Both the recoverable strain of superelasticity and the two-way shape memory strain of the present alloy are the highest among the bulk polycrystalline HTSMAs. The theoretical maximum transformation strain was calculated with energy-minimization theory using the crystal structure information of martensite and austenite obtained from in situ synchrotron high-energy X-ray diffraction experiments to help understand the superelastic behavior of the present alloy. Combining the advantages of low cost and easy fabrication, the present bulk polycrystalline (Ni50Mn35.5Ti14.5)99.8B0.2 alloy shows great potential for high-temperature shape memory applications. This work is instructive for developing cost-effective high-performance HTSMAs.

High-temperature shape memory alloys (HTSMAs) show enormous potential for applications as energy conversion devices, actuators and sensors in automotive, aerospace, and energy exploration industries, but they suffer from strength decrease and microstructural instability at elevated temperatures, rendering it difficult to achieve satisfactory high-temperature superelasticity. Here, a novel Ti20Hf15Zr15Cu25Ni25 high-entropy HTSMA exhibiting large superelasticity with a fully recoverable strain of 4.0% at temperatures up to 285°C is designed with the high-entropy alloy concept by employing the sluggish diffusion and severe lattice distortion effects to suppress thermal softening. This work illuminates the design of novel high-performance functional materials for high-temperature applications.

High-efficiency elastocaloric refrigeration requires high-performance elastocaloric materials with both large surface areas to promote heat exchange rate and large elastocaloric effects to increase the amount of heat transfer. Ni–Ti shape memory alloys (SMAs) are the most promising elastocaloric materials but they are difficult to process by conventional methods due to their poor manufacturability. Here, we successfully developed Ni–Ti SMAs with large elastocaloric effects by additive manufacturing which has the capability to fabricate complex geometries with large surface areas. The phase transformation temperatures of these additively manufactured Ni–Ti SMAs, fabricated by selective laser melting (SLM), can be tuned by varying the SLM processing parameters and/or post heat treatments and thus tunable large elastocaloric effects were achieved at different temperatures, which can be used for different applications. Owing to its large transformation entropy change and high yield strength as a result of precipitation hardening, the aged SLM fabricated alloy exhibits a remarkably large elastocaloric effect with an adiabatic temperature change as high as 23.2 K, which is among the highest values reported for all Ni–Ti SMAs fabricated by both conventional methods and additive manufacturing. Furthermore, by virtue of the high yield strength and low stress hysteresis of the aged alloy, this large elastocaloric effect shows good stability during cycling. The achievement of such large elastocaloric effects in alloys fabricated by near-net-shape additive manufacturing may accelerate the implementation of high-efficiency elastocaloric refrigeration. This study is instructive for the development of advanced high-performance solid-state refrigeration materials by additive manufacturing.

Ternary energetic structural material (ESM) Ni–Al–CuO was prepared by cold spraying, and its mechanical properties studied under quasi-static-state and dynamic compression conditions. Energy release characteristics including the ignition temperature, energy release, and combustion wave velocity were characterized in both the thermal explosion and self-propagating combustion modes. The results reveal that the yield stress of Ni–Al–CuO is 50 MPa higher than that of Ni–Al. The initial reaction temperature was found to be 450 °C, much lower than the temperature of the reaction between Al and CuO and corresponding to the reaction of Ni and Al. In addition, more energy was released by Ni–Al–CuO ESM (859.2 J/g) than by Ni–Al (735.4 J/g). The combustion wave velocity of the Ni–Al–CuO coating was about 90 mm/s. Self-propagating combustion of Ni–Al–CuO proceeded via a multistage reaction, during which the Al–CuO reaction was triggered by the Ni–Al reaction.

Superelasticity associated with martensitic transformation has found a broad range of engineering applications, such as in low-temperature devices in the aerospace industry. Nevertheless, the narrow working temperature range and strong temperature sensitivity of the first-order phase transformation significantly hinder the usage of smart metallic components in many critical areas. Here, we scrutinized the phase transformation behavior and mechanical properties of multicomponent B2-structured intermetallic compounds. Strikingly, the (TiZrHfCuNi)

Superelasticity associated with the martensitic transformation has found a broad range of engineering applications1,2. However, the intrinsic hysteresis3 and temperature sensitivity4 of the first-order phase transformation significantly hinder the usage of smart metallic components in many critical areas. Here, we report a large superelasticity up to 15.2% strain in [001]-oriented NiCoFeGa single crystals, exhibiting non-hysteretic mechanical responses, a small temperature dependence and high-energy-storage capability and cyclic stability over a wide temperature and composition range. In situ synchrotron X-ray diffraction measurements show that the superelasticity is correlated with a stress-induced continuous variation of lattice parameter accompanied by structural fluctuation. Neutron diffraction and electron microscopy observations reveal an unprecedented microstructure consisting of atomic-level entanglement of ordered and disordered crystal structures, which can be manipulated to tune the superelasticity. The discovery of the large elasticity related to the entangled structure paves the way for exploiting elastic strain engineering and development of related functional materials. NiCoFeGa single crystals exhibit large non-hysteretic superelasticity over broad temperature and composition ranges. It is attributed to the continuous phase transition with applied stress, which is related to the fluctuation of entangled ordered and disordered crystal structures.

Background: A consensus regarding optimum treatment strategies for locally advanced gastric cancer (LAGC) has not yet been reached. We aimed to evaluate the efficacy of various treatment modalities for LAGC and provided clinicians salvage options under real-world situation. Methods: Medical charts of patients with LAGC who underwent radical resection plus adjuvant chemotherapy or chemoradiotherapy from July 2003 to December 2014 were included. Validation cohort were selected from SEER database between 2004 and 2014. Kaplan-Meier and Cox proportional hazardous models were used to evaluate the overall survival (OS), cancer-specific survival (CSS), and disease-free survival (DFS). Propensity score matching (PSM) was used to adjust for potential baseline confounding. Results: A total of 350 patients were included and divided into D1 dissection plus chemotherapy group (D1CT, n = 74), D1 dissection plus adjuvant chemoradiotherapy group (D1CRT, n = 69), D2 dissection plus adjuvant chemotherapy group (D2CT, n = 134), and D2 dissection plus adjuvant chemoradiotherapy group (D2CRT, n = 73). PSM identified 50 patients in each group. After PSM, better DFS (P for D2CRT vs. D1CT, D1CRT, and D2CT was 0.001, 0.006, and 0.001, respectively) and OS (P for D2CRT vs. D1CT, D1CRT, and D2CT was 0.001, 0.011, and 0.022, respectively) were found for the D2CRT group (mean, OS = 110.7months, DFS = 95.2 months) than the other groups. Similar findings were further validated in the Surveillance, Epidemiology, and End Results database (SEER) cohort. In addition, patients in the D1CRT group achieved similar survival outcomes to those in the D2CT group (mean OS, 72.8 vs. 59.1 months, P = 0.86; mean DFS, 54.4 vs. 34.1 months, P = 0.460). Conclusions: The results of the study indicated the better role for D2CRT in treating the LAGC, meanwhile, the patients treated with D1CRT might achieve similar survival as that of D2CT patients.

Magnetic shape memory alloys (MSMAs) have attracted great interests due to their multifunctional properties associated with external-field-induced martensitic transition, such as magnetostrain, magnetoresistance, magnetocaloric effect and elastocaloric effect. Search for MSMAs displaying a unique combination of strong metamagnetic transition and stable, large caloric effect is nowadays very active. Here we report the simultaneous achievement of a strong metamagnetic transition as well as a large magnetic-field-induced entropy change of 17.4 J kg−1 K−1 under 2 T and a stable, large elastocaloric effect with adiabatic temperature change of ∼5.0 K during more than 2100 mechanical cycles, in a Ni-Fe-Co-Mn-Sn MSMA. Such combination in a single material has never been reported in the literature. Furthermore, we demonstrate that fully reversible metamagnetic transition and consequently large, reversible multicaloric effect can be achieved by increasing magnetic field from 0 T to 2 T at zero stress and decreasing field from 2 T to 0 T at a uniaxial stress of 23.5 MPa. This dual-stimulus magnetic-mechanical multicaloric cooling cycle also provides an opportunity for achieving reversible magnetoresistance and magnetostrain under the coupling of a low magnetic field and small stress, which is beneficial for practical applications. The high cyclic stability of large caloric effects is ascribed to the good geometric compatibility at the interface between austenite and martensite as revealed by employing multiscale characterization approaches, including in-situ synchrotron high-energy X-ray diffraction and transmission electron microscopy. This study has great implications on developing high-performance multifunctional alloys with magnetostructural transition for actuation, magnetic recording and solid-state refrigeration applications.

Chemical vapor transport deposition (CVTD) is an effective method for preparing large tungsten coatings for space thermionic reactors. In this study, a high-density, high-work-function polycrystalline tungsten coating was prepared using a WCl6 transport agent in a concentric tube-type closed transport system. The relationship between the kinetics and the microstructures of the CVTD polycrystalline tungsten coating at the substrate temperature of 1593 K-1793 K and system pressure of 15.93 Pa-106.8 Pa was studied, which provided a basis for the preparation of high-quality tungsten coatings. At a low temperature or a low pressure, the activation energy was approximately 2 kJ/mol, the deposition rate was almost independent of the temperature changes, and the control mechanism was mass transport limited. The tungsten coating had nodules on the surface with pores in the grain boundaries and grew preferentially along . At a high temperature and a high pressure, the apparent activation energy was approximately 90 kJ/mol, the value of order was approximately 1, and the control mechanism in this process range was surface limited. The tungsten coating exhibited a hexagonal pyramidal structure, and the growth direction was preferred along . The average work function of the tungsten coating prepared at a temperature of 1673 K and a system pressure of 106.80 Pa was as high as 5.20 eV.

A metastable β titanium alloy, Ti–2Al-9.2Mo–2Fe (wt.%), with athermal ω phase after quenching has been subjected to high strain rate (∼3000 s−1) compression at ambient temperature by Spilt Hopkinson Pressure Bar arrangement. Reverse β-to-ω transformation was investigated by transmission electron microscopy during deformation. Furthermore, the novel distribution of athermal ω phase in {332} twinning and stress-induced martensitic was observed. We reveal that such novel distribution is attributed to the influence of ω phase on {332} twinning and stress-induced martensite transformation (SIMT) based on the viewpoint of the instability of the lattice structure of metastable β phase. Furthermore, a new process of twinning and SIMT in current alloy with ω phase was proposed.

In this study, the microstructure evolution of β-Mg17Al12 in Mg 9Al–0.5Zn–0.12Ag alloys aged at 175 °C for 18, 36, and 72 h was investigated. The results indicate that β-Mg17Al12 precipitates contain discontinuous precipitates and continuous precipitates. The interface between a discontinuous precipitation phase and the matrix appears with either a straight or a stepped morphology. Existing misorientation dislocations at a straight interface disappear with increasing aging time. For continuous precipitates, a [ 11 5 ¯ ]β//[ 2 1 ¯ 1 ¯ 0 ]α, ( 41 1 ¯ ) β//( 101 1 ¯ )α orientation relationship (OR) was observed, and a stereogram of this new OR was calculated, the results of which are discussed herein. As aging time is prolonged, the continuous precipitates grow, and their OR develops toward a common Burgers OR. The yield strengths of the alloys aged for 18 and 36 h exhibit no significant differences owing to a better strengthening effect achieved by the new OR in the 18-h aged samples than that of the Burgers and Potter OR. As the aging time approaches 72 h, a larger grain size reduces the yield strength of the alloy.

TRAF6 has been reported to be associated with poor prognosis in non-small-cell lung cancer (NSCLC). However, its precise role in tumor development has not been elaborated. In the present study, the function and the mechanism by which TRAF6 contributes to development were intensively investigated. TRAF6 was found to be overexpressed in primary NSCLC tumor tissue and all tested cell lines. Knockdown of TRAF6 with shRNA substantially attenuated NSCLC cell proliferation and anchorage-independent growth. Moreover, tumor glycolysis, such as glucose consumption and lactate production, also significantly impaired. In TRAF6-deficient cells, hexokinase-2 expression was significantly reduced, which was caused by the decrease of HIF-1α transcriptional activity. Further investigations demonstrated that TRAF6 played an important role in the regulation of Akt activation, and exogenous overexpression of constitutively activated Akt substantially rescued glycolysis suppression in TRAF6 knockdown cells. The results of the xenograft model confirmed that downregulation of TRAF6 in NSCLC tumor cells dramatically restrained tumor growth in vivo. Taken together, our studies revealed the mechanism by which TRAF6 exerts its role in NSCLC development and suggested TRAF6 maybe was a promising candidate target for lung cancer prevention and therapy.

Ternary Ni-Al-Al12Mg17 and binary Ni-Al reactive materials were obtained by cold spraying. The reactive performance of both materials was compared to explore the influence of the Al12Mg17 additive. According to differential scanning calorimetry–thermogravimetric analysis–derivative thermogravimetry, the Ni-Al-Al12Mg17 thermal explosion reaction produced a peak at 480 °C, being 160 °C lower than that of binary Ni-Al. The high-resolution element surface distribution clearly showed the microstructure evolution after controlled annealing and revealed that the rapid oxidation reaction of liquid Mg played a critical role in the occurrence of the thermal explosion reaction in air. During the self-propagating combustion process, the Al12Mg17 additive acted as “ignition spots,” and the Ni-Al intermetallic reaction was ignited by combustion of Mg. The sustained power provided by the Mg combustion promoted the continuous reaction in the Ni-Al matrix. The combustion wave velocity of the Ni-Al-Al12Mg17 material was almost doubled, from 60-100 to 150-200 mm s−1, demonstrating the suitability of the Al12Mg17 additive for enhancing the performance of Ni-Al-based reactive material.

The mechanical behavior of a metastable β titanium alloy, Ti-2Al-9.2Mo-2Fe (wt%), was studied through high compression strain rate (~3000 s−1) at ambient temperature by Spilt Hopkinson Pressure Bar (SHPB) tests after solution treatment at 850 ℃ for 0.5 h and 950 ℃ for 1 h. The mechanism of deformation and microstructure evolution was investigated by electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). Multiple deformation mechanisms, including primary and secondary {332} twinning, stress-induced martensite, and stress-induced ω-phase and dislocation slips, were identified in specimens subjected to solution treatment at 850 ℃ for 0.5 h. In contrast, only primary and secondary {332} twinning and dislocation slips were detected in specimens subjected to solution treatment at 950 ℃ for 1 h. The athermal ω precipitation produced after solution treatment and elevated temperature generated during dynamic loading played a crucial role in the different deformation mechanisms observed in the two different specimens. Moreover, the deformation mechanisms active during plastic deformation in the different strain regimes affected the development of different textures in the Ti-2Al-9.2Mo-2Fe alloys from each regime.

Polymorphism and polymorphic transitions are attracting considerable interest because of their significant effect on the phase stability, switchable properties, and the atomic rearrangement mechanism in materials. Here, by employing in situ high-pressure synchrotron radiation X-ray diffraction, we reveal surprisingly abundant polymorphic transitions in an Al0.6CoCrFeNi high-entropy alloy (HEA). The original body-centered cubic (bcc) phase transfers to an orthorhombic phase at ∼ 10.6 GPa during compression at room temperature, and the orthorhombic phase remains stable up to ∼ 40 GPa. When the lattice stress is released entirely, the orthorhombic phase can further transform into a body-centered tetragonal structure. On the other hand, when the original bcc phase is heated to high temperatures, a face-centered cubic phase forms, and it can further transform to a hexagonal close packing phase by applying pressure. In total, we observed five polymorphs in the Al06 HEA, and they all can exist at ambient conditions. The complex chemistry and the pressure/temperature tuned lattice distortion may play a key role in introducing and stabilizing the rich polymorphs in the Al06 HEA. Our findings may bring new insights into the correlation between lattice distortion and phase stability/transitions of HEAs and help to explore HEAs with novel structures and properties.

Laser melting deposition (LMD) technology enables the use of complex titanium alloy parts in ballistic applications such as lattice armors and warheads. The effect of the α phase of a LMD Ti-6.5Al-1Mo-1V-2Zr titanium alloy during compression at a high strain rate of 3000 s⁻1 was investigated. Various morphologies and textures of the α phase of the LMD alloy were obtained by annealing at different temperatures at the β transus, followed by furnace cooling. It was found that all the α phases of the annealed microstructures exhibit two fiber textures, α and 16 ¯ 19>α, parallel to the building direction. The reason is that the β directions of the prior-β grains were parallel to the building direction. Due to a high Schmidt factor, {1012} twinning occurs in the α phases with the α fiber texture during the high-strain rate deformation. After annealing at 970 °C, the volume fraction of the α phases with the α fiber texture increases significantly to 51.4 vol%, which leads to a significant improvement of 14.3% in the uniform ductility strain. Moreover, with an increase in the annealing temperature from 930 °C to 970 °C, the flow strength of the sample decreases slightly by 2%.

Ni-Co-Mn-Sb alloys can exhibit large elastocaloric effect characterized as stress-induced entropy change ΔSσ. However, the intrinsic large brittleness of polycrystalline alloys makes it difficult to directly measure the stress-induced temperature change ΔTad. Here, we demonstrate large elastocaloric effect in a directionally solidified Ni45.7Co4.2Mn37.3Sb12.8 alloy with enhanced mechanical properties. Large ΔTad up to 9.4 K was realized through compressive stress-induced martensitic transformation with a low transformation strain of 1.5%. Moreover, with integrating large ΔSσ up to 25.4 Jkg−1 K−1 and wide working temperature window of 46 K, a giant refrigeration capacity RCσ of 930 Jkg−1 was achieved under the compressive stress of 250 MPa.

The magnetostriction of Fe-Ga alloys is significantly affected by the Ga content, which displays two positive peaks with increasing Ga concentration. This work presents a systematic structural investigation of rapidly-cooled Fe-Ga alloys by the synchrotron-based high-energy x-ray diffraction. Ga-rich clusters are evidenced for the alloys beyond the first magnetostriction peak, which is identified by the anomalous peak broadening for the (200) fundamental reflection and a shrink of lattice parameter. The generation of Ga-rich clusters in A2 matrix results in the sudden decrease of magnetostriction after the first magnetostriction peak. These findings are important for designing high-performance Fe-Ga magnetostrictive alloys by structural tuning.

Large reversible caloric effects covering a broad temperature region are essential for high-efficiency and environment-friendly solid-state caloric refrigeration that can potentially replace the traditional vapor-compression-based cooling technology. Here, we report the simultaneously achieved large reversible magnetocaloric and elastocaloric effects in a Ni43Co6Mn40Sn11 magnetic shape memory alloy. A reversible near-room-temperature magnetic entropy change ΔSm of as high as 19.3 J kg−1 K−1 under 5 T was experimentally obtained and the corresponding adiabatic temperature change ΔTad was estimated to be 7.7 K. Meanwhile, a large reversible elastocaloric effect with a directly measured ΔTad up to 7.1 K was attained. The elastocaloric effect exhibits high cyclic stability with no apparent degradation during 380 cycles of loading and unloading. Furthermore, we propose and demonstrate the utilization of the multicaloric approach under the coupled uniaxial stress and magnetic field to enlarge the refrigeration temperature region of reversible caloric effects. By combining the reversible magnetocaloric and elastocaloric effects and the reversible multicaloric effect under the coupling of uniaxial stress and magnetic field in the hysteresis region, large reversible caloric effects covering a broad temperature region from 257 K to 383 K can be obtained. This study may pave the way for designing advanced caloric materials with cyclically stable and reversible large caloric effects and wide refrigeration temperature region for solid-state refrigeration.

A tungsten carbide coating was prepared by atmospheric chemical vapor deposition (CVD) with tungsten hexafluoride (WF6), hydrogen, and dimethyl ether (DME) as the reaction gases, under a dimethyl ether partial pressure (PDME) of 3.2–21.0 kPa and a temperature of 550–600 °C. The phase compositions of the coatings are W2C + W and W3C + W, and it is found that when PDME is low, the coating has a lamellar structure, but at a high PDME, the lamellar structure and fibrous tissue are simultaneously present in the scanning electron microscope (SEM) image. In the latter case, no delamination was found, which was visible at a low PDME. In addition, as the PDME increases, the deposition rate of the coating decreases, and ultimately, the coating cannot continue to grow. The growth model of the tungsten carbide coating based on the kinetics of the chemical vapor deposition of tungsten by the hydrogen reduction of tungsten hexafluoride was proposed, and the influences of PDME and temperature on the coatings were discussed and the orientation relationship between W and W2C in high resolution transmission electron microscopy (HRTEM) was analyzed.

We have investigated the superelastic behavior and elastocaloric effect in [011] oriented Ni50Fe19Ga27Co4 single crystals. The superelasticity is absent in a temperature gap of 60 K. At the critical temperature of 388 K, the stress oscillation and audible noise can be found during the superelastic deformation, indicating the occurrence of burst-like transformation. Such a burst character leads to a novel non-linear increase of martensitic transformation start stress with temperature, and an enhanced hysteresis loss. In addition, a large elastocaloric temperature window of 40 K and a maximum cooling effect of −6.1 K have been obtained.

Near-fully-dense (porosity v ) between Ni and Al reactants and an expression was proposed, giving an activation energy of 129 kJ/mol.

In face-centered cubic alloys, an outstanding combination of strength and ductility can be achieved through reducing the stacking fault energy. In this paper, the mechanical response and microstructural evolution of Ni-27 W alloys (with 27 wt% W) are studied. The Ni-27 W solid solution alloys have a face-centered cubic structure. A stacking fault energy of ~67 mJ/m2 is evaluated by the thermodynamic method. The yield stress, ultimate tensile strength, and percentage elongation to fracture of the Ni-27 W alloys are 415 MPa, 1285 MPa and 42%, respectively, which shows a high strain hardening capacity. The deformation mechanism of the Ni-27 W alloys has been investigated by means of transmission electron microscopy, electron backscatter diffraction, and high-energy x-ray diffraction at the deformation stages with true strains of 0.02, 0.1, 0.2, and 0.3. A fiber texture with and parallel to the tensile direction is gradually formed under uniaxial deformation. Planar dislocation structure is clearly observed, the spacing of which gets thinner as increasing the deformation strain. Planar slip dominates the plastic deformation, which results in a high strain hardening capacity.

Owing to their complex microstructures, the strain hardening of titanium alloys remains poorly understood. Therefore, the plastic deformation processes of the α and β phases in dual-phase TC6 (Ti–6Al–2.5Mo–1.5Cr–0.5Fe–0.3Si) titanium alloy were investigated via high-energy X-ray diffraction with in situ tensile loading. Dislocation density evolution in both the α and β phases was quantified via X-ray diffraction line profile analysis complemented by transmission electron microscopy measurements. The strain hardening rate calculated based on this evolution matched the strain hardening behaviors shown in the stress-strain curves. Furthermore, the effect of interactions between subgrain boundaries and slip systems were elucidated through transmission electron microscopy (TEM) observations. The evolution of strain hardening rate, as well as the dislocation density, was correlated with and well explained by the typical microstructures formed in different deformation regimes.

Hysteresis associated with martensitic transformation in shape memory alloys (SMAs), which reflects the energy dissipation during transformation, seriously harms the functional fatigue life and energy conversion efficiency. Exploration of advanced SMAs with both low stress hysteresis and large superelastic strain is of crucial importance for practical applications. Here, we achieved low-hysteresis large tensile superelasticity in a Ni-Co-Mn-Sn magnetic shape memory microwire, the bulk counterpart of which is highly brittle and can hardly be applied. This microwire exhibits oligocrystalline structure with bamboo-like grains and thus good compatibility during deformation and transformation. As a result, excellent tensile superelasticity with a recoverable strain as high as 6% was obtained, which represents the highest value reported heretofore in Ni–(Co)–Mn–Z (Z=In, Sn, Sb) magnetic SMAs. Strikingly, this tensile superelasticity exhibits very low stress hysteresis of 23 MPa (with the overall strain of 6%), which is only one eighth of that in the bulk. The present microwire shows very promising application prospects in cyclic high-frequency actuators and high efficiency energy conversion devices under the coupling of stress and magnetic field.

Chemical vapor deposited (CVD) high-purity tungsten can be manufactured as electron emitters in thermionic fuel elements. Exposed surface planes of the emitter emit electrons and affect the efficiency and load capacity of the thermionic fuel element. In order to determine the electron emission planes of the emitter, the metallurgic structures, the preferred orientation and the as-deposited surface morphology of CVD tungsten have been investigated. In this work, high-purity (over 99.99%) tungsten was achieved by two different precursors: hydrogen reduction of tungsten hexafluoride (WF 6 ) and thermolysis of tungsten hexachloride (WCl 6 ). The microstructures of CVD tungsten were characterized by metallography analysis, X-ray diffraction (XRD), electron backscattered diffraction (EBSD), and white light interference (WLI). Tungsten fabricated by hydrogen reduction of WF 6 and thermolysis of WCl 6 has ⟨100⟩-preferred columnar microstructures. However, the latter exhibits larger columnar grains and preferred ⟨100⟩ less. The preferred orientation is caused by the higher growth rate of the ⟨100⟩ orientation and competition between the ⟨100⟩ orientations of different grains. The as-deposited surface consists of tiny pyramids, with ⟨100⟩ axis and {111} side faces. In contrast to tungsten produced by hydrogen reduction of WF 6 , the pyramid on tungsten synthesized via thermolysis of WCl 6 contains small {110} facets on the four edges. Therefore, tungsten made via thermolysis of WCl 6 is a better candidate for thermionic fuel elements, because the higher work function of {110} planes enables better output efficiency.

Synchrotron-based high-energy X-ray diffraction is used to explore the physical origin of large magnetostriction in DyCo 2 , an RT 2 compound (R = rare earth, T = Co, Fe), by tracing the crystal structural change as a function of temperature and magnetic field. When the DyCo 2 compound is zero-field cooled down below the Curie temperature T C , the high-temperature cubic lattice is distorted into a tetragonal structure, associated with an expansion of unit cell volume. When a magnetic field is applied gradually from 0 to 6 T below T C , no changes in the peak positions for tetragonal (800) T and (008) T peaks are observed, whereas their relative peak intensities are gradually changed. The intensity changes generated during magnetic field increasing are reversed stepwise with decreasing the magnetic field. Our experimental results suggest that the large magnetostriction in DyCo 2 is caused by the crystallographic domain-switch mechanism (or rearrangement of tetragonal domains). The diffraction elastic strain is not detected under the field up to 6 T. The present investigations provide a fundamental understanding of the mechanisms of the large magnetostriction in RT 2 compounds with Laves phases.