Heat treatment plays a crucial role in tailoring the microstructure and mechanical properties of AMed TMCs, while the role of reinforcements remains insufficiently understood. In this study, TiB/IMI834 composites were fabricated via laser-directed energy deposition and subjected to alpha + beta solution treatments with varying cooling rates. Rapid cooling retained fine lamellae, while slower cooling promoted coarsening and partial equiaxialization. Meanwhile, metastable TiB underwent dissolution and coarsening via Ostwald ripening, fragmenting the network into whiskers. Crucially, TiB-induced alpha variant selection occurs during both additive manufacturing and subsequent heat treatment, particularly under the AC condition, with the presence of three preferred misorientations (0 degrees/[001], 58.57 degrees/[010], and 90 degrees/[010]). Selected alpha variants exhibited larger grain areas and equiaxed morphologies. Mechanistic analysis reveals that alpha variants satisfying 0 degrees/[001] and 58.57 degrees/[010] preferentially nucleate on (100)TiB and (101)TiB facets, while the 90 degrees/[010] variant originated from microstructural heredity. Therefore, AC composite achieved a peak compressive strength of 2020 + 34 MPa and fracture strain of 22.9% + 0.3%. High-temperature tensile strength reached 920 + 4 MPa at 600 degrees C and 690 + 5 MPa at 700 degrees C. These findings offer novel insights into TiB-induced alpha variant selection and a theoretical basis for optimizing AMed TMCs via heat treatment strategies.

Interfaces play a crucial role in strain hardening, slip accommodation, and plastic flow stability of dual-phase alloys. The orientation relationship (OR) between phases critically governs the crystallographic discontinuity and imposes geometric constraints on the activation of deformation modes. In dual-phase 19Al-20Fe-20Co-41Ni high-entropy alloys, we demonstrate that weakening the Kurdjumov-Sachs (K-S) OR between the L12 and B2 phases via moderate plastic deformation and recrystallization, significantly improves ductility without sacrificing strength. The threefold increase in ductility compared to the as-cast alloy is attributed to a B2→body-centered tetragonal (BCT) transformation, promoted by weakening the interface OR. In contrast, the as-cast alloy with K-S OR constrained B2 remains untransformed. In situ synchrotron tensile testing confirms the phase transformation evolves progressively. Our analysis of the expected strain contribution reveals that transformation preferentially occurs in B2 grains adjacent to highly deformable neighbors. These findings highlight the critical role of OR in governing phase transformation and deformation. The orientation relationship between phases governs crystallographic discontinuity and imposes constraints on the activation of deformation modes. Here, weakening the orientation relationship between L12 and B2 phases in a dual-phase high-entropy alloy via plastic deformation and recrystallization significantly improves ductility without sacrificing strength.

The Fe-Ni based classical Invar alloy and the Fe-Ni-Co based super Invar alloy are the basis for designing multicomponent alloys with low thermal expansion. In this work, we applied in-situ high-throughput experimental methods to map chemical composition, crystal structure, coefficient of thermal expansion (CTE) and magnetism in the Fe-Ni-Co system. The distribution of CTE (80-200 degrees C) measured by the in-situ micro-beam Xray diffraction on the combinatorial materials chips (CMC) showed low CTE regions in agreement with previous reports. Combined with the MOKE measurements, the mu-e relation of the Fe-Ni-Co ternary FCC phase is found to follow the reported FCC Fe-Ni alloys in the Slater-Pauling curve. A low CTE region is centred at e = 26.7 and mu = 1.26 mu B in the Slater-Pauling curve. The observed low CTE zone not only matches with the classical Invar and super Invar alloys but also agrees with the reported Fe-Ni-Co based multicomponent alloys with a small amount of doping (< 5 at%) by Cu, Cr, Mn etc. The effect of Cr addition (> 5 at%) to Fe-Ni-Co alloys on the Invar effect is further discussed in terms of the interplay between magnetism and austinite stability.

The high entropy alloy Al0.3CoCrFeNiTi0.15 was originally tailored for high-temperature applications through the addition of a small amount of Ti, which promotes the formation of L12-structured strengthening phase. In this study, we aimed to enhance its mechanical properties using laser power bed fusion (LPBF) technology. Compared to the traditional casting methods, the LPBF-processed sample exhibited a remarkable increase in both strength and elongation at room temperature, with the product of strength and elongation reaching 29.7 GPa%, nearly double the previous value of 15.9 GPa%. LPBF processing not only refines the grain size but also leads to the absence of the L12 phase and a decrease in the B2 phase content. We uncovered the coexistence of segregation of Ti and Al elements, along with in-situ formation of nano B2 phase on the cellular structure. The LPBF-processed alloy without any post-retreatment achieved a tensile strength of 864 MPa at 700 degrees C. This study demonstrates the feasibility of improving the mechanical properties of HEAs via the LPBF process. The potential to directly integrate LPBF-processed parts into production has the capability to substantially decrease costs related to post- processing and significantly shorten the development cycle of the production.

Two-dimensional (2D) materials, particularly transition metal dichalcogenides (TMDs), have garnered significant attention in the nanoscale piezoelectric field due to their high crystallinity and ability to withstand large strains. Through density-functional theory calculations, we have discovered that monolayer H-phase CrS2 and CrSe2 exhibit antiferromagnetic semiconducting properties, in contrast to the previously held belief that they were nonmagnetic (NM) semiconductors. While the piezoelectric coefficients of NM CrS2 and CrSe2 are comparable to those of MoS2, their antiferromagnetic ground states demonstrate significantly enhanced piezoelectric coefficients (d(11)) of 27.66 pm V-1 and 52.36 pm V-1, respectively. These values exceed that of MoS2 by an order of magnitude, marking the highest recorded for TMD materials and the highest in 2D magnetic materials to date. The greatly enhanced piezoelectric responses in the antiferromagnetic states of CrS2 and CrSe2 compared to their NM states arise from three primary factors. Firstly, the displacement of the Wannier center under strain is more pronounced in the antiferromagnetic state, leading to a greater change in dipole moment (enhanced clamped-ion contribution). Secondly, there is a heightened polarization change due to internal atomic distortions (internal-strain term) in response to macroscopic strain in the antiferromagnetic state. Thirdly, the material undergoes a softening of the elastic coefficient in its antiferromagnetic state. These findings open new avenues for designing high-performance piezoelectric and magnetic multifunctional materials.

Eutectic high-entropy alloys (EHEAs) exhibit promising characteristics for achieving both high strength and good ductility owing to their diverse deformation mechanisms. In this study, a gradient B2-BCT phase transformation was observed in a deformed Al19Fe20Co20Ni41 (at. %) EHEA. The XRD patterns indicate a gradual transformation from the B2 phase to the BCT phase, a process significantly influenced by the strain applied during tensile testing. The gradient transition region between B2 phase and BCT phase occurs within a single grain, where the lattice constant changes step by step. Such a mechanism holds huge potential for enhancing the mechanical properties of EHEAs.

The lattice constants of metallic solid solutions are composition-dependent and closely correlated to many physical properties such as solid solution strengthening and lattice misfit etc. The traditional way of measuring the composition-dependent lattice constant is severely limited by the ability to sample the composition space efficiently. We develop a high-throughput combinatorial materials chip (CMC) experimentation combined with the Bayesian inference approach to model the composition-dependent lattice constants (CDLC) of multicomponent solid solutions quantitatively. Based on a direct-fitting model Ω CMC-S on the CMC data, an improved model Ω BI is derived by utilizing the bulk alloy data via the Bayesian inference approach on three ternaries (Ni–Fe–Co/Cu/Cr) and one quaternary (Ni–Fe–Co–Cr). The Ω BI is overall more accurate and reliable than the Ω CMC-S in terms of R 2 . Furthermore, the ability to quantify the uncertainties of the coefficients in Ω BI provides decision support for robust alloy design. Our model also reveals the nonlinear CDLC relationship in Cr-containing systems, which supports the local chemical order effect. By contrasting the outcomes from the other three theoretical models, we demonstrate the advantage of the current model and the overall comprehension of the studied systems.

PURPOSE:As one of the pathogenic factors of cerebral small vessel disease, venous collagenosis may result in the occlusion or stenosis of deep medullary veins (DMVs). Although numerous DMVs can be observed in susceptibility-weighted MRI images, their diameters are usually smaller than the MRI resolution, making it difficult to segment them and quantify their sizes. We aim to automatically segment DMVs and measure their diameters from gradient-echo images. METHODS:A neural network model was trained for DMV segmentation based on the gradient-echo magnitude and phase images of 20 subjects at 7 T. The diameters of DMVs were obtained by fitting measured complex images with model images that accounted for the DMV-induced magnetic field and point spread function. A phantom study with graphite rods of different diameters was conducted to validate the proposed method. Simulation was carried out to evaluate the voxel-size dependence of measurement accuracy for a typical DMV size. RESULTS:The automatically segmented DMV masks had Dice similarity coefficients of 0.68 ± 0.03 (voxel level) and 0.83 ± 0.04 (cluster level). The fitted graphite-rod diameters closely matched their true values. In simulation, the fitted diameters closely matched the true value when voxel size was ≤ 0.45 mm, and 92.2% of DMVs had diameters between 90 μm and 200 μm with a peak at about 120 μm, which agreed well with an earlier ex vivo report. CONCLUSION:The proposed methods enabled efficient and quantitative study of DMVs, which may help illuminate the role of DMVs in the etiopathogenesis of cerebral small vessel disease.

The effect of Ti addition on mechanical and oxidation properties of a Cu-containing alumina-forming austenitic alloys (AFA) was investigated. The studied base alloy lacking Ti, with the Ni content of ~34.5 wt.%, exhibited a limited creep/rupture life of only 67 h at 750°C/150 MPa. The introduction of 0.5 wt. % Ti addition increased the amount of L12-structured strengthening phase within the matrix, and enhanced the creep/rupture life to 1701 h at the same condition. However, further Ti addition deteriorated the Al2O3 protective scale, leading to rupture after 950 h in the alloy with 1 wt.% Ti. Hence, the performance of AFA steel is sensitive to the Ti content, which impacts both the strengthening phase and oxidation resistance.

Cancer is one of the leading causes of mortality worldwide, making it a public health concern. A novel series of pyrrolidine-carboxamide derivatives 7a-q were developed and examined in a cell viability assay utilizing a human mammary gland epithelial cell line (MCF-10A), where all the compounds exhibited no cytotoxic effects and more than 85% cell viability at a concentration of 50 μM. Antiproliferative activity was evaluated in vitro against four panels of cancer cell lines A-549, MCF-7, Panc-1, and HT-29. Compounds 7e, 7g, 7k, 7n, and 7o were the most active as antiproliferative agents capable of triggering apoptosis. Compound 7g was the most potent of all the derivatives, with a mean IC50 of 0.90 μM compared to IC50 of 1.10 μM for doxorubicin. Compound 7g inhibited A-549 (epithelial cancer cell line), MCF-7 (breast cancer cell line), and HT-29 (colon cancer cell line) more efficiently than doxorubicin. EGFR inhibitory assay results of 7e, 7g, 7k, 7n, and 7o demonstrated that the tested compounds inhibited EGFR with IC50 values ranging from 87 to 107 nM in comparison with the reference drug erlotinib (IC50  = 80 nM). 7e, 7g, 7k, 7n, and 7o inhibited CDK2 efficiently in comparison to the reference dinaciclib (IC50  = 20 nM), with IC50 values ranging from 15 to 31 nM. The results of inhibitory activity assay against different CDK isoforms revealed that the tested compounds had preferential inhibitory activity against the CDK2 isoform.

PURPOSE:The effectiveness of prospective motion correction (PMC) is often evaluated by comparing artifacts in images acquired with and without PMC (NoPMC). However, such an approach is not applicable in clinical setting due to unavailability of NoPMC images. We aim to develop a simulation approach for demonstrating the ability of fat-navigator-based PMC in improving perivascular space (PVS) visibility in T2-weighted MRI. METHODS:MRI datasets from two earlier studies were used for motion artifact simulation and evaluating PMC, including T2-weighted NoPMC and PMC images. To simulate motion artifacts, k-space data at motion-perturbed positions were calculated from artifact-free images using nonuniform Fourier transform and misplaced onto the Cartesian grid before inverse Fourier transform. The simulation's ability to reproduce motion-induced blurring, ringing, and ghosting artifacts was evaluated using sharpness at lateral ventricle/white matter boundary, ringing artifact magnitude in the Fourier spectrum, and background noise, respectively. PVS volume fraction in white matter was employed to reflect its visibility. RESULTS:In simulation, sharpness, PVS volume fraction, and background noise exhibited significant negative correlations with motion score. Significant correlations were found in sharpness, ringing artifact magnitude, and PVS volume fraction between simulated and real NoPMC images (p ≤ 0.006). In contrast, such correlations were reduced and nonsignificant between simulated and real PMC images (p ≥ 0.48), suggesting reduction of motion effects with PMC. CONCLUSIONS:The proposed simulation approach is an effective tool to study the effects of motion and PMC on PVS visibility. PMC may reduce the systematic bias of PVS volume fraction caused by motion artifacts.

Ni-Co-Fe based alloy 783 is commonly employed as bolt material in power plants. Its initial state possesses a gamma matrix strengthened through B2-type beta phase and L1(2)-type gamma' phase. Over prolonged service, the alloy displays an observed increase in strength along with certain embrittlement. After 100 and 123 months of service at 600 degrees C, a pine-like phase enriched with Co and Fe occurs in the matrix, which is confirmed to be a BCC phase with a lattice parameter of 2.87 & Aring;. These BCC precipitates also manifest within the coarse beta particles and are coherent with the B2 phase, showing a cuboidal shape. Thermodynamic calculations suggest the transformation from the ordered B2 phase to the disordered BCC phase at temperatures below 670 degrees C. The identification of the order-disorder phase transition deepens the understanding of phase transition after long-term service in alloy 783 and the related mechanical properties evolution in addition to previous works.

Ni-Co-Fe based alloy 783 is commonly employed as bolt material in power plants. Its initial state possesses a γ matrix strengthened through B2-type β phase and L12-type Υ' phase. Over prolonged service, the alloy displays an observed increase in strength along with certain embrittlement. After 100 and 123 months of service at 600°C, a pine-like phase enriched with Co and Fe occurs in the matrix, which are confirmed to be a BCC phase with a lattice parameter of 2.87 Å. These BCC precipitates also manifest within the coarse β particles and are coherent with the B2 phase, showing a cuboidal shape. Thermodynamic calculation suggests phase transformation from the ordered B2 phase to the disordered BCC phase at temperatures below 670°C. The identification of the newly emerged phase in alloy 783 contributes to a deeper understanding of how mechanical properties evolve in relation to microstructural changes after long-term service.

Al0.3CoCrFeNiTix (x = 0.025, 0.075, 0.15) high-entropy alloys (HEAs) were designed to investigate the impacts of Ti addition and the aging temperature (700-900 degrees C) on the mechanical properties of the alloys. The alloy aged at 700 degrees C with x = 0.15 yielded the highest ultimate tensile strength (UTS) and large fracture elongation at both room temperature and 700 degrees C. The UTS is 1299 MPa with fracture elongation up to 31.6% at room temperature, and 769 MPa with 32.5% at 700 degrees C. The product of strength and elongation of Al0.3CoCrFeNiTi0.15 is higher than the reported value of other similar FCC HEAs at elevated temperature. The reason for the outstanding balanced mechanical properties of the alloy is the uniformly distributed L1(2) and B2 particles. Ti promotes the precipitation of L1(2) phase and the precipitation temperature increased from 770 to 890 degrees C as Ti content increased. The amount of B2 phase reached a maximum at 900 degrees C with x = 0.15. The B2 particles at grain boundaries render the different variation tendency of ductility at 700 degrees C from that at room temperature.

While the microstructure at the grain boundary of hot-deformed nanocrystalline Nd-Fe-B magnets is intensively studied, limited works have been devoted to the deformation behavior of the Nd2Fe14B matrix grain, especially for micrometer scale grains and at high temperatures. In this study, the plastic deformation behavior of the Nd2Fe14B matrix grains was studied by uniaxial compression from 1050 degrees C to 1120 degrees C using both anisotropic and isotropic sintered Nd-Fe-B magnets. The anisotropic magnets were orientated with the c-axis 0 degrees , 45 degrees and 90 degrees to the loading axis. According to the Arrhenius-type power law relationship, the stress exponent n increased from 1.5 to 2.7 when the c-axis changed from 0 degrees to 90 degrees to the loading direction and the corresponding apparent activation energies Q increased from 384 to 437 kJ/mol. Although the observed n > 1 coincides with the interface-reaction controlled solution-precipitation creep mechanism, the determined Q is much larger than those reported in the nanocrystalline magnet. Our study conferred the first demonstration of short straight dislocations array on the (001) plane in the 45 degrees-orientated anisotropic specimen after 10% height reduction. Grain elongation and local misorientation inside the grain were most obvious in the 45 degrees-oriented specimen after compression. The extent of the local misorientation agreed well with the spacing corresponding to geometrically necessary dislocation. The results reveal that grain rotation via grain boundary sliding and dislocation-mediated deformation were operable depending on the loading direction when the micro-sized magnets were deformed above 1000 degrees C.

Co-diffusion of heavy rare-earth elements and Co has been reported to improve the remanence and coercivity of Nd-Fe-B magnet at high temperatures without trade-off. Two low-melting point alloys Pr50Tb20Cu15Co15 and Y15Pr40Tb15Cu15Co15 were designed in this work to simultaneously enhance the remanence and coercivity at 150°C in sintered magnet by grain boundary diffusion. The remanence increased from 1.24 T to 1.28 and 1.31 T at 150°C together with the increase of coercivity from 0.3 T to 0.89 and 0.77 T after diffusion. The temperature coefficients of remanence (20–150°C) were reduced from −0.11 %/°C to −0.07 and −0.06 %/°C by Pr50Tb20Cu15Co15 and Y15Pr40Tb15Cu15Co15 respectively. The improvement of temperature coefficients is attributed to the microstructure effect without changing the Curie temperature. The low melting point of the diffusion alloys and Y are attributed to breaking the remanence–coercivity dilemma with reduced Tb and Co usage.

Van der Waals (vdW) materials afford unprecedented opportunities for control of electronic properties by utilizing the stacking degree of freedom. An intriguing frontier, largely unexplored, is the stacking of charge density wave (CDW) phases that is a broken‐symmetry state with periodically modulated charge density and the atomic lattice. Employing density functional theory, it is uncovered that the stacking order can play a significant role in the quantum phase transitions of layered 1T‐TaSe 2 with a striking 2D CDW order. By controlling the vertical stacking order of CDWs, bulk 1T‐TaSe 2 can host various electronic phases including quasi‐1D and 3D metals and band insulators. Particularly, the ground‐state stacking configuration shows 3D metallicity due to the enhanced intralayer and interlayer electron hopping, and the second lowest energy configuration shows band insulating behavior via interlayer dimerization, implying potential metal‐insulator transition. In ultrathin‐layer 1T‐TaSe 2 , not only the stacking order but also the thickness dictate the electronic properties. While the monolayer is a Mott insulator, the bilayer (trilayer) is a band insulator (metal). More interestingly, the four‐layer emerges as an insulator or a semimetal dependent on its stacking order. The wide‐tunable electronic properties of 1T‐TaSe 2 CDW compound will open a new pathway for designing novel quantum devices.

Ni-rich ternary cathode materials have attracted attention for their high energy density. The fast capacity attenuation is one of the main obstacles limiting the applications of LiNi0.83Co0.12Mn0.05O2 (NCM83). Aiming to improve electrochemical performance, we modify the NCM83 cathode particles with Mg and La doping by co-precipitation. The pristine NCM83 has a capacity retention rate of 61.8% after 200 charge–discharge cycles at 1C. The cycle stability of Mg-La co-modification NCM83 increases significantly, although its initial capacity slightly decreases. The co-modification sample delivers a higher capacity retention rate of 83.8%, which also has a better rate capability. The synergistic effect of Mg-La co-modification upgrades the reversibility of the redox reaction during cycling and improves the mechanical property of the particles. Therefore, the cyclability of NCM83 is greatly improved.

Two Al0.3CoCrFeNi and Al0.3CrFeNi2 high-entropy alloys (HEAs) containing similar to 0.07% carbon were designed to explore the feasibility of replacing expensive Co with Ni. After aging at different temperatures (550, 700 and 900 degrees C), both alloys exhibited an excellent balance of strength and ductility, i.e. ultimate strength (>640 MPa) and elongation (>40%) at room temperature. Compared with the Al0.3CoCrFeNi HEA, the Al0.3CrFeNi2 alloy showed an increased volume fraction of L1(2) phase, the emergence of M23C6 and the elimination of B2 precipitation. The cost-effective Al0.3CrFeNi2 HEAs aged at 550 degrees C rendered a tensile yield strength of 245.8 MPa and an elongation of 22.4% at 700 degrees C compared with 151.8 MPa and 25.0% of the Al0.3CoCrFeNi. This increase of yield strength is attributed to the strengthening from the L12 precipitates. Thermodynamic calculation (Thermo-Calc) confirms the increased volume fraction of L12 phase in the HEA as the Ni content doubled. Calculated Gibbs energy of the M23C6 phase is systematically lower in the Al0.3CrFeNi2 explains the absence of M23C6 in the Co-containing Al0.3CoCrFeNi under similar heat treatment conditions. As the aging temperature increased, coarse M23C6 appeared at grain boundaries and reduced the high-temperature ductility of the Al0.3CrFeNi2 alloy.