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Effects of microstructural evolutions on electrochemical corrosion properties and passive film characteristics of precipitation-strengthened (Ni 2 Co 2 FeCr) 92 Al 4 Nb 4 high-entropy alloys (HEAs) were investigated in a saline environment. Compared with single-phase FCC alloys, the appearance of nano-sized L1 2 particles increases the metastable pitting activities and slightly reduces the pitting potential, while the lamellar D0 19 phase further deteriorates the localized corrosion resistance. The chemical composition and oxide state of passive films are closely related to the different precipitation scenarios. The corrosion morphologies of the single-phase and L1 2 -strengthened alloys are dominated by pitting, whereas the intergranular corrosion (IGC) and intragranular dealloying-like corrosion occur in the D0 19 -strengthened alloy. [Display omitted] • Effects of the L1 2 phase and D0 19 phase on the electrochemical corrosion behavior of HEAs were revealed. • The characteristics of surface passive films are closely related to the precipitation scenarios. • The structure-corrosion-mechanics relationship of HEAs was established. • A bilayer passive film with a Fe-rich outer layer and a Cr-rich inner layer was directly observed in the L1 2 -strengthened HEA. • IGC occurs in the D0 19 -strengthened HEA due to the localized micro-galvanic corrosion. [ABSTRACT FROM AUTHOR]

Developing strong-yet-ductile alloys with wide temperature capabilities is crucial for modern industrial and scientific applications; however, this is often difficult to realize using conventional wisdom. In this work, we innovatively designed a nanoparticle-strengthened high-entropy alloy (HEA) through elaborate compositional design and thermomechanical regulation. The designed HEA exhibits extraordinary mechanical properties across a wide temperature range (−196∼1000 °C), resulted from the unique microstructures consisting of high-density hierarchical L1 2 nanoparticles combined with serrated grain boundaries. A high ultimate tensile strength of 1355 MPa combined with a ductility of 35.0 % were achieved when tested at 25 °C. The tensile strength and ductility were enhanced simultaneously with the decrease of temperature from 25 to −196 °C. More prominently, the intermediate-temperature intergranular embrittlement, a severe ductility loss at 600∼800 °C for most conventional superalloys, is effectively suppressed even under high tensile stress, which is attributed to the high resistance to crack propagation of serrated grain boundaries. An apparent anomalous yielding behavior occurred at 700 °C, leading to an ultrahigh yield strength of ∼1045 MPa while maintaining a large ductility of ∼22.1 %. Meanwhile, an excellent strength of 325 MPa can still be maintained even at 1000 °C combined with a good ductility over 25 %. Systematic characterizations revealed that such a temperature-dependent mechanical behavior is highly related to various deformation substructures activated at different temperatures. This work would open a pathway to developing a series of advanced alloys with superior strength and ductility over a wide temperature range. [Display omitted] [ABSTRACT FROM AUTHOR]

• Two kinds of EHEAs are designed by changing the relative content between Ni and Fe. • Ordered B2 phase shows superior radiation tolerance to FCC and BCC phases. • Strong radiation tolerance material can be designed by phase-composition control. Eutectic high-entropy alloys (EHEAs) take advantage of heterogeneous crystal structures, numerous interfaces, and multicomponent composition designs, implying a potential radiation tolerance in the nuclear environment. In this work, we employed the He ion irradiation to study the irradiation behavior of two types EHEAs (Fe 42 Ni 31 Al 17 Cr 10 , abbreviated as Fe42, and Fe 47 Ni 26 Al 17 Cr 10 , abbreviated as Fe47) with different phase designs. The results showed that the FCC + B2 constituted Fe42 EHEA and BCC + B2 constituted Fe47 EHEA retained their general phase-composition features up to ∼ 1.2 dpa at 1073 K, while the long-range order of B2 phase was slightly disrupted in both alloys and more severe in the Fe42 EHEA. The quantification on He bubbles formation in different phases further indicated that the ordered B2 phase in Fe47 EHEA has a superior radiation resistance with smaller bubble size and less population. The differences in phase compositions and structures were believed to influence the vacancy-mediated helium diffusion during irradiation, which can account for the He bubble behaviors in the two kinds of alloys. The analysis on the width of bubble denuded zone along the phase boundary further suggested a higher energy barrier for the vacancy migration in the B2 phase, which consistently supported our inference on the underlying mechanism of bubble formation resistance of Fe47 EHEA. We believe that this work will provide a new strategy for designing EHEAs with excellent resistance to irradiation at elevated temperatures. [Display omitted] [ABSTRACT FROM AUTHOR]

Molecular dynamic simulations were performed for liquid Al 72 Ni 16 Co 12 to study the transport properties and the Stokes-Einstein relation (SER). It was observed that the self-diffusion coefficient for Co is much lower and α -relaxation time is much longer than the other two elements. The viscosity as a function of temperature was obtained with a method of reversed non-equilibrium molecular dynamics simulation. The SER in terms of viscosity and α -relaxation time for all elements was evaluated. It is found that the effective diameter for Co increases abnormally with the decrease of the temperature. The breakdown of SER for Co between self-diffusion coefficient and viscosity or α -relaxation time happens in the whole temperature range covered in this work, whereas the breakdowns of SER for both Al and Ni occur respectively at 1500 K and 1200 K in term of viscosity and α -relaxation time, which are far above the critical temperature of mode coupling theory, T c , around 814 K according to transport properties, and 797 K based on the α -relaxation time. The decoupling of element dynamics and the dynamic heterogeneity are studied by calculating the ratio of the two diffusivities for different elements, D 1 / D 2 , and the non-Gaussian parameter. To check the structural-dynamics correlation, the total and partial pair correlation functions are calculated. It is proposed that for Co the decoupling of self-diffusion coefficient and viscosity or α -relaxation time persists at all temperatures due to the strong interactions between Co atoms. And the sudden increase of the dynamic heterogeneity, accompanied by a subtle change of liquid structure, is supposed to be the reason for the abnormal breakdown of SER for Al and Ni at a temperature far above T c. • Transport properties are computed and the abnormal breakdown of Stokes-Einstein relation for liquid Al-Ni-Co are evaluated. • The breakdown temperature is much higher than the critical temperature of mode coupling theory and the liquidus temperature. • The decoupling of element dynamics, the dynamic heterogeneity, and the structure-dynamics correlation are studied. [ABSTRACT FROM AUTHOR]

To realize near net-shaping of hard-to-process intermetallics is an often challenging but critical issue to their wider industrial applications. In this work, we report that an intermetallic Ti–22Al–25Nb has been successfully fabricated by selective laser melting (SLM). The as-printed samples show a high room-temperature ultimate tensile strength ∼1090 MPa and excellent ductility ∼22.7%; both values are higher than most conventionally fabricated Ti–22Al–25Nb intermetallic. We clarify the mechanical performance achieved by detailed microstructure analysis, including dislocation and phase constitution. It is proposed that high-density dislocation networks significantly contribute to the strength and ductility, which are further enhanced by the favorable phase constitution, including the nano-scale O phase precipitates within the disordered β phase and disappearance of the brittle α 2 phase in the microstructure. Phase evolution during solidification, particularly regarding the O phase's formation, has also been clarified using in-situ laser heating, high-temperature synchrotron X-ray diffraction and Scheil simulation. It is demonstrated that the O phase formation involves both displacive transition (B2 → B19) and chemical ordering (B19 → O). The metastable B19 phase (as an intermediate stage) may be formed by shearing cubic B2 phase along (110) [ 1 − 11 ] direction into an orthorhombic structure under high residual stress. Furthermore, a demonstrative part of turbine blade has been fabricated to highlight the importance of SLM in fabricating critical structural part like the hard-to-process intermetallics. Image 1 [ABSTRACT FROM AUTHOR]

Dynamic damage and fracture of conductive glass are investigated using a split Hopkinson pressure bar, implemented with in situ X-ray phase contrast imaging (XPCI) and optical imaging for comparison. Quantitative comparison between X-ray and optical images demonstrates that XPCI exhibits much higher resolution in resolving micro cracks and dynamic fracture modes. Multiple predamage and fracture modes of glass samples under dynamic loading are revealed with XPCI to depend on competing nucleation of initial flaws across scales, which give rise to a scattered fracture strength distribution. The fracture strengths increase with increasing strain rates due to accelerated crack propagation and damage growth. Quantitative gray-scale statistical analysis of XPCI and optical images yields spatial and temporal evolutions of damage. Unexpected plateaus essentially without damage growth are observed on the damage curves of glass, deviating from conventional theoretical predictions. The damage plateaus are attributed to growth, closure and re-expansion of inclined main cracks, due to interactions of stress waves with crack tips. The current results also demonstrate a reliable experimental technique for dynamic damage characterization of brittle materials. [ABSTRACT FROM AUTHOR]

Ti45Al8Nb alloy (in at.%) is designed to be an important high-temperature material. However, its fabrication through laser-based additive manufacturing is difficult to achieve. We present here that a good understanding of the surface structure of raw material (i.e. Ti45Al8Nb powder) is important for optimizing its process by selective laser melting (SLM). Detailed X-ray photoelectron spectroscopy (XPS) depth profiling and transmission electron microscopy (TEM) analyses were conducted to determine the surface structure of Ti45Al8Nb powder. An envelope structure (∼54.0 nm in thickness) was revealed for the powder, consisting of TiO 2  + Nb 2 O 5 (as the outer surface layer)/Al 2 O 3  + Nb 2 O 5 (as the intermediate layer)/Al 2 O 3 (as the inner surface layer)/Ti45Al8Nb (as the matrix). During SLM, this layered surface structure interacted with the incident laser beam and improved the laser absorptivity of Ti45Al8Nb powder by ∼32.21%. SLM experiments demonstrate that the relative density of the as-printed parts can be realized to a high degree (∼98.70%), which confirms good laser energy absorption. Such layered surface structure with appropriate phase constitution is essential for promoting SLM of the Ti45Al8Nb alloy. [ABSTRACT FROM AUTHOR]

The poor formability and high-temperature oxidation resistance of Ti 2 AlNb-based intermetallics (for example, Ti–22Al–25Nb at. %, nominal composition) are considered to be the main obstacles that need to be overcome in critical high-temperature applications. In this study, micro-arc oxidation (MAO) was applied to Ti 2 AlNb additively manufactured by selective laser melting (SLM). SLM offered advanced forming capabilities, while MAO enhanced the mechanical and chemical properties of the materials. The MAO coating comprised an amorphous layer, a nanocrystalline oxide layer, and a continuous TiO 2 layer. The multi-layers structure of MAO coating significantly improved the high-temperature oxidation resistance by blocking inward oxygen diffusion. The pulse frequency had significant effects on the microstructure, hardness, and wear resistance of the MAO coatings. Low pulse frequency led to thick MAO coatings with coarse surface roughness, large crater-like pores, and serious surface cracks. High pulse frequency improved the hardness and wear resistance of the MAO coatings. A pulse frequency of 1000 Hz deteriorated the wear resistance of MAO coating caused by the poor metallurgical bonding between the substrate and MAO coating. This study demonstrated the possibility of employing MAO to enhance the critical properties of the Ti 2 AlNb-based intermetallics fabricated by SLM. [Display omitted] • MAO coating improves hardness, wear and oxidation resistance of SLMed Ti 2 AlNb. • MAO coating contains amorphous layer, nanocrystalline layer and thin TiO 2 layer. • Amorphous phase formation mechanism was clarified by calculating glass forming ability. [ABSTRACT FROM AUTHOR]

Ti–5Al–5Mo–5V–1Cr–1Fe is a near β-type Ti-alloy. It has been widely used in large loading-carry structures in aircrafts due to its excellent mechanical properties. For near-β titanium alloys, DRX (dynamic recrystallization) in hot deformation process can eliminate the bimodal microstructure and refine microstructure, which helps to improve the alloy performance. So, the hot deformation behavior of Ti–5Al–5Mo–5V–1Cr–1Fe alloy was characterized in the temperature range of 750–950 °C and the initial strain rate range of 0.01–10 s −1 by the constitutive model, the critical conditions of DRX and EBSD (Electron Backscattered Diffraction) technique. The constitutive model of Ti–5Al–5Mo–5V–1Cr–1Fe alloy during hot deformation can be well described by Arrhenius hyperbolic sine function. The calculation results show that the ratio of critical strain and peak strain is about 0.64. Under the experimental conditions in this research, Ti–5Al–5Mo–5V–1Cr–1Fe alloy exhibits two soften mechanisms of (DRV) dynamic recovery and DRX. The DRX phenomenon of Ti–5Al–5Mo–5V–1Cr–1Fe alloy exists in all of hot deformation conditions. Only the extents of DRX are different. There are several nucleation mechanisms of DRX in the process of hot deformation of Ti–5Al–5Mo–5V–1Cr–1Fe alloy in this study. [ABSTRACT FROM AUTHOR]

Correlation between the feedstock powder and the as-printed products is well expected in laser powder bed fusion (LPBF). However, the inheritance/heredity relationship between the feedstock powder and the products remains broadly overlooked since most atomized powders are printed without any modification. This study addresses the inheritance issue through comparing the hydrogenation/dehydrogenation (HDH) Ti powder with the ball-milled (BM) Ti powder, as well as the respective as-printed samples. Rietveld refinement, focused ion beam, electron backscatter diffraction, and transmission electron microscopy are employed to characterize the microstructure; uniaxial tensile tests and fractographic observation are performed for the mechanical analysis; single-track finite element simulations are conducted to reveal the varied powder-bed properties. A "core-shell" powder structure has been generated through the ball milling modification. Nano-crystallites in the "shell" and stress-induced twins have brought significant grain refinement to the BM powder. A β-to-α m massive transformation has been observed in the samples printed using HDH powder, whereas the microstructure changes to fully-martensitic when using BM powder as the feedstock. Excellent mechanical performance (∼1000 MPa tensile strength with ∼20% ductility) have been achieved through inheriting the fine microstructure and oxygen content from the BM powder, which are induced by the powder modification process. This study has therefore unveiled the comprehensive correlation between the feedstock powder and the as-printed Ti, highlighting a novel methodology for developing additively-manufactured, cost-effective, and high-performance materials through tailoring the feedstock powder. • The influence of ball-milling modification on Ti powder has been clarified. • Systematic comparisons of different feedstock powders and as-printed samples. • The inheritance relationship between feedstock and products has been revealed. • Developing novel materials through tailoring the feedstock powders. [ABSTRACT FROM AUTHOR]

Correlation between the feedstock powder and the as-printed products is well expected in laser powder bed fusion (LPBF). However, the inheritance/heredity relationship between the feedstock powder and the products remains broadly overlooked since most atomized powders are printed without any modification. This study addresses the inheritance issue through comparing the hydrogenation/dehydrogenation (HDH) Ti powder with the ball-milled (BM) Ti powder, as well as the respective as-printed samples. Rietveld refinement, focused ion beam, electron backscatter diffraction, and transmission electron microscopy are employed to characterize the microstructure; uniaxial tensile tests and fractographic observation are performed for the mechanical analysis; single-track finite element simulations are conducted to reveal the varied powder-bed properties. A "core-shell" powder structure has been generated through the ball milling modification. Nano-crystallites in the "shell" and stress-induced twins have brought significant grain refinement to the BM powder. A β-to-α m massive transformation has been observed in the samples printed using HDH powder, whereas the microstructure changes to fully-martensitic when using BM powder as the feedstock. Excellent mechanical performance (∼1000 MPa tensile strength with ∼20% ductility) have been achieved through inheriting the fine microstructure and oxygen content from the BM powder, which are induced by the powder modification process. This study has therefore unveiled the comprehensive correlation between the feedstock powder and the as-printed Ti, highlighting a novel methodology for developing additively-manufactured, cost-effective, and high-performance materials through tailoring the feedstock powder. • The influence of ball-milling modification on Ti powder has been clarified. • Systematic comparisons of different feedstock powders and as-printed samples. • The inheritance relationship between feedstock and products has been revealed. • Developing novel materials through tailoring the feedstock powders. [ABSTRACT FROM AUTHOR]

Abstract: This study employs a combination of the least-squares, an autoregressive (AR) model and a Kalman filter (LS+AR+Kalman) in short-term prediction of the earth orientation parameters (the length-of-day (LOD), UT1-UTC and polar motion). Compared to least-squares and AR model (LS+AR), the combination of least-squares, AR model and Kalman filter performs better in the prediction of UT1-UTC and LOD, and shows a significant improvement in prediction of the polar motion. [Copyright &y& Elsevier]

Abstract: In this note, we prove the existence of Nash equilibria in infinite normal form games with compact sets of strategies and continuous payoffs by constructing Nash mappings. [ABSTRACT FROM AUTHOR]

To determine the effects of phosphorus nutrition on chilling tolerance of photosynthetic apparatus, tomato (Lycopersicon esculentum Mill. cv. Kenfengxin 2002) plants were raised under different P contents and subjected to 7 d of chilling at 9/7 °C. After chilling (2 h or 7 d) plant growth, P content in tissue, gas exchange and chlorophyll fluorescence were measured. Decreasing P concentration [P] in the nutrient solution markedly reduced plant growth and the chilled plants exhibiting higher optimum [P] than the unchilled plants. Decreasing [P] significantly decreased light saturated net photosynthetic rate (PNsat), maximum carboxylation velocity of Rubisco (Vcmax), maximum potential rate of electron transport contributed to Rubisco regeneration (Jmax), quantum efficiency of photosystem (PS) 2 (ΦPS2) and O2 sensitivity of PNsat (PSO2) and this trend was especially apparent in chilled plants. [ABSTRACT FROM AUTHOR]

Abstract: This paper characterizes upper semicontinuity and lower semicontinuity of weakly efficient solution mapping and efficient solution mapping S on the space of continuous -dimension-vector-real-valued objective functions on a nonempty compact set X. As applications, some more interesting results about the properties of weakly efficient solutions and efficient solutions are obtained, such as the upper semicontinuity of S at f in implies the closedness and connectedness of the set of efficient solutions, any essential weakly efficient solution of f can be approximated by a sequence of efficient solutions of f (i.e., ), and in the sense of Baire categories “most” of vector optimization problems in for efficient solutions are essential, and so on. [Copyright &y& Elsevier]

Abstract: Starting from nitrate aqueous solutions with citrate acid and polyethylene glycol (PEG) as additives, YVO4:Dy3+ phosphors were prepared by a two-step spray pyrolysis (SP). The obtained phosphors had spherical morphology. The luminescence properties of YVO4:Dy3+ phosphors were investigated by changing the concentration of Dy3+ and the annealing temperatures, respectively. The emission intensity of the phosphors increased with increasing the annealing temperature due to the increase of the crystallinity and particles size. The optimum concentration for the luminescence of Dy3+ was determined to be 2mol% of Y3+ in YVO4 host. [Copyright &y& Elsevier]

Abstract: Kinetic effect of the atom-attachment at the solid–liquid interface and thermal undercooling are incorporated into the analysis of the eutectic growth in bulk undercooled melts. When crystallization products contain intermetallic compounds or other topologically complex phases, the kinetic effect will significantly alter the eutectic growth behaviors, and maintain the coupled eutectic growth to higher undercoolings. Such phenomena are exhibited more notably in alloy systems where the eutectic phases have a narrow crystallization temperature range at the eutectic composition. The growing interface is essentially unstable in the undercooled melt owing to the existence of a negative temperature gradient in the liquid along the growth direction, and tends to break down into dendritic morphology. Considering that the thermal diffusion length is much larger than the eutectic lamellar spacing, the eutectic dendrite is treated as a thermal dendrite. It is found that the thermal undercooling at the eutectic dendrite tip increases with the increasing growth velocity, but its proportion of the total undercooling is higher at the lower undercoolings. In other words, the effect of the thermal diffusion on the eutectic growth is more significant at the low growth velocities. [Copyright &y& Elsevier]

Abstract: Starting from nitrate aqueous solutions with citrate acid and polyethylene glycol (PEG) as additives, YVO4:Eu phosphors were prepared by a two-step spray pyrolysis (SP) and citrate-gel (CG) methods, respectively. The morphology and luminescence properties of YVO4:Eu phosphors prepared from SP method were investigated by changing the concentration of precursor solution, the concentration of PEG and the annealing temperatures, respectively. The emission intensity of the phosphors increased with increasing the annealing temperature and solution concentration due to the increase of the crystallinity and particles size. Certain PEG concentration was necessary for obtaining solid spherical particles, and the optimum emission could be observed when the concentration of PEG was 0.02g/ml. Compared with the spherical YVO4:Eu phosphors prepared by SP method, the CG-derived non-spherical YVO4:Eu phosphors showed lower emission intensity when annealed at 1000 and 1200°C. The optimum concentration for the luminescence of Eu3+ is determined to be 7mol% of Y3+ in YVO4 host. [Copyright &y& Elsevier]

Abstract: A novel modification treatment to improve the electrochemical performance of amorphous, nano-sized MnO2 is proposed in this paper. An “in situ polymerization reaction” method was employed to obtain the MPz(dtn)4 or PMPzS8–MnO2 composition material. TG, IR, XRD and TEM methods were adopted for material characterization. The experimental results reveal that the amorphous nature and small particle size (10–20nm) of the parent MnO2 material can be preserved after MPz(dtn)4 or PMPzS8 modification treatment. Galvanostatic charge and discharge was carried out to test the electrochemical property of the resulting material. It indicates that all modified products show an improved electrochemical performance comparing with their parent MnO2 phase as being reflected by the higher capacity and enhanced cycle life. To investigate the mechanism for improved electrochemical performance, ac impedance technique was employed. Preliminary results suggest that the capacity and the cycleability of the composition material are improved in some degree which may be ascribed to the increasing of intercalation/deintercalation from inter-granular modified compounds. [Copyright &y& Elsevier]

Abstract: Y2O3:Eu phosphors were prepared by a spray pyrolysis process followed by post annealing. Morphology control of Y2O3:Eu phosphor particles in the spray pyrolysis process was attempted by using citric acid (CA) and polyethylene glycol (PEG) as additives in the spray precursors. Three different morphologies of Y2O3:Eu phosphor particles, viz. smooth spheres, rods and flakes, were obtained in the presence of PEG with different molecular weights or without the presence of PEG, respectively. Possible mechanisms for the formation of Y2O3:Eu particles with the different morphologies have been proposed. It is shown that the spherical Y2O3:Eu phosphors have higher photoluminescent intensity than those with other morphologies. [Copyright &y& Elsevier]

Abstract: Raw carbon nanotubes are synthesized by the electric arc method and pre-doped with lithium. Electrochemical intercalation of lithium into the raw carbon nanotubes pre-doped with lithium is investigated. The results show that the irreversible and reversible capacity of the sample is about 500 and 200mAhg-1, respectively. The reversible capacity is higher than that of the raw carbon nanotubes and the open carbon nanotubes. The main reason is that LiNO3 absorbed by the carbon nanotubes is decomposed into LiNO2 at high temperature, and the lithium nitrite can form a film before the electrode contacts the electrolyte. The Li-containing compound film on the electrode surface can prevent the solvent to decompose into other products, so little charge is consumed in the electrolyte decomposition process. Complementary characterization techniques (elemental analysis, X-ray diffraction, scanning electron microscopy, constant-current charge–discharge tests) are used for a full structural characterization of the carbon nanotubes pre-doped with lithium and the electrochemical intercalation of lithium. [Copyright &y& Elsevier]

This paper presents an approach to the interpolation of angular feedrate for bi-parameter curve paths in multi-axis machining. A bi-parameter curve is the intersection of a parametric surface and an implicit surface. A tool path is identified by a position curve and an orientation curve, both of which are generated based on the bi-parameter curve. The angular feedrate interpolator calculates the tool position and orientation at each sampling cycle according to the specified angular feedrates and the given tool path. The paper analytically relates the angular arc-length derivatives to the time derivatives of the parameters along the path making use of both angular feedrates and angular feed acceleration. The results are then used to interpolate the parameters of the bi-parameter curve leading to an accurate calculation of the position and orientation of the cutting tool. A general parametric surface has been used to verify the effectiveness of the algorithm. The bi-parameter curves of the surface have been computed for arbitrarily selected intersecting cylinders. [Copyright &y& Elsevier]

Starting from nitrate aqueous solutions with citric acid and polyethylene glycol (PEG) as additives, Y3Al5O12:Eu (YAG:Eu) phosphors were prepared by a two-step spray pyrolysis (SP) method. The obtained YAG:Eu phosphor particles have spherical shape, submicron size and smooth surface. The effects of process conditions of the spray pyrolysis on the crystallinity, morphology and luminescence properties of phosphor particles were investigated. The emission intensity of the phosphors increased with increasing of sintering temperature and solution concentration due to the increase of the crystallinity and particles size, respectively. Adequate amount of PEG was necessary for obtaining spherical particles, and the optimum emission intensity could be obtained when the concentration of PEG was 0.10 g/ml in the precursor solution. Compared with the YAG:Eu phosphor prepared by citrate-gel (CG) method with non-spherical morphology, spherical YAG:Eu phosphor particles showed a higher emission intensity. [Copyright &y& Elsevier]

By using metal nitrates as starting materials and citric acid as complexing agent, Y3Al5O12 (YAG) and Y3Al5O12:Eu (1 mol%) (YAG:Eu) powder phosphors were prepared by a citrate–gel method. The formation process of YAG and YAG:Eu were investigated by means of XRD, TG–DTA and FT-IR spectra. The purified crystalline phases of YAG and YAG:Eu were obtained at 800 °C. The crystalline YAG:Eu phosphors showed an orange–red emission with 5D0–7F1 (591 nm) as the most prominent group, whose intensity was dependent on the pH value of the starting solution, citric acid content and firing temperature. It has been found that the suitable pH and citric acid/metal ratio are 3 and 2 for obtaining the highest emission intensity, respectively. The emission intensity increases steadily with increasing the annealing temperature from 800 to 1200 °C, and nearly remains constant after 1200 °C. Furthermore, great differences were observed for the lifetimes and the charge transfer band of Eu3+ in crystalline and amorphous states of YAG. [Copyright &y& Elsevier]

Ti 2 AlNb (Ti–22Al–25Nb at.%, nominal composition) intermetallic is essential to aerospace industry from a weight reduction perspective, and brings a possibility of replacing some Ni-based superalloys. Despite evaporation of element Al (from its original composition 22.8 at.% to 18.5 at.%), selective laser melting (SLM) technology offers distinct advantages in fabricating Ti 2 AlNb intermetallic with superior room-temperature properties. A full understanding of corresponding heat treatment mechanism is the key to utilize well the SLM-prepared Ti 2 AlNb at high temperatures. This study aims to clarify the relationship between the microstructure and mechanical propensities of SLM-prepared then heat-treated Ti 2 AlNb, to ultimately achieve promising mechanical performances at high temperatures. For this research purpose, a series of heat treatments were conducted, and the corresponding microstructures, mechanical properties were systematic studied by advanced characterization techniques. Results show that the mechanical properties at both room and high temperatures depend on heat treatment adopted. The samples solution-treated at 950 °C and then aged at 700 °C show promising room and high temperature strengths due to the formation of acicular O, α 2 and grain boundary α 2 phases. However, their ductility was poor. Aging at 830 °C reduces the strength, but significantly improves the ductility due to the appearance of rodlike O phase and the increase of B2/β phase proportion. The alloy possesses promising strength and ductility (611 MPa, 10.0%) and high thermal stability at 650 °C. It is further demonstrated that the heat-treated Ti 2 AlNb possesses promising specific strength, even higher than that of as-cast Inconel 718 superalloy. The developed alloy, therefore, has a high potential for the industries requiring high-temperature performance and weight reduction. • A suitable heat treatment schedule was established for the SLM-prepared Ti 2 AlNb. • Heat-treated Ti 2 AlNb has high specific strength comparable to Inconel718 at 650 °C. • The relationships between mechanical properties and microstructures were established. • Phase transition mechanism during heat treatment was clarified. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the magnetic and specific heat properties of polycrystalline MnCr2O4 were investigated, mainly by focusing on the spiral order transition around T s . With increasing magnetic field, the magnetic anomaly around T s in the M–T curve is gradually suppressed. However, an external magnetic field up to 5T has no evident influence on the spiral magnetic transition as revealed by specific heat measurements. Upon cooling below T s , AC susceptibility displays no frequency dependence, but the coercivity increases abruptly. Applying external pressure increases the coercivity at 5K, implying the strengthening of the spiral order. It is suggested that with decreasing temperature across T s , the spiral component develops in the direction perpendicular to the easy axis of the parent collinear ferri-magnetic phase and does not contribute to the saturation magnetization. [Copyright &y& Elsevier]

Abstract: The structural and electronic properties of () clusters have been investigated through density functional theory. Our results show that the triangular shape (A) clusters and capped shape (B) clusters are generally stabler than W-shaped (C) clusters. It is shown that the HOMO (highest occupied molecular orbital)–LUMO (lowest unoccupied molecular orbital) gaps vary inversely to the average bond length. We also investigated spectra of () clusters, which shows that the dominant peaks near 3.5eV are contributed from the electrons of , and . [Copyright &y& Elsevier]

Ti–22Al–25Nb (at.%) intermetallic is a light weight, high performance, high temperature material with density of merely ˜60% of Ni-based superalloys. The advent and rapid development of selective laser melting (SLM) enable direct fabrication of the Ti–22Al–25Nb intermetallic into complex geometry parts, promising for various critical applications. This paper is dedicated to better understanding the effects of hatch distance, an important but often underestimated processing factor, on microstructure and mechanical properties of the SLM-prepared Ti–22Al–25Nb. Along with analytical means such as transmission electron microscopy (TEM) and electron backscatter diffraction (EBSD), finite element simulation has also been employed to explore the underlying mechanisms. It is determined that the highest mechanical properties are achieved at a hatch distance of 0.16 mm due to the following factors: (a) High density dislocation, (2) favorable phase features, and (3) high relative density. As-fabricated parts of micro-turbine engine using the optimized parameters are provided in the end of the study to demonstrate the capability of SLM to manufacture high quality and delicate structural parts of the Ti–22Al–25Nb intermetallic. [ABSTRACT FROM AUTHOR]

This study presents a novel approach for the fabrication of commercially pure titanium (CP–Ti) components. The approach conferred superb strength to CP-Ti without sacrificing its ductility. A yield strength of 807 MPa combined with 19.15% elongation was realized through selective laser melting (SLM) by using a high-power laser and incorporating solute atoms from the Ar−N 2 reactive atmosphere. Mechanical properties and microstructures of the as-printed CP-Ti were systematically investigated. Transmission electron microscopy, electron backscatter diffraction, and atom probe tomography were employed to reveal the mechanism underlying the in-situ reaction between CP-Ti and the reactive atmosphere. Results suggested that nitrogen generally dissolved in the α′-Ti matrix as interstitial solute atoms. The beneficial N content has a critical limit of ~0.43 wt%. The ductility of CP-Ti will decrease drastically if its N content exceeds this limit. A constitutive model was developed for describing the tensile deformation behavior of the in-situ strengthened CP-Ti over various solute contents and grain sizes. This work demonstrates a promising methodology for the fabrication of high-performance metallic components and extends the fundamental understanding of SLM process under the reactive atmosphere. [ABSTRACT FROM AUTHOR]

Corrosion-resistant alloys with high strength and large ductility are desirable for applications in harsh environments where high structural load-carrying capacity is required. In this work, we designed an L1 2 -strengthened high-entropy alloy (HEA) of composition (NiCo) 77 Cr 13 Al 5 Nb 5 (at.%) that combines excellent mechanical properties and good corrosion resistance. The formation of a thin passive film of non-stoichiometric compounds with an amorphous structure, characterized by an enrichment of Cr 2 O 3 and Nb 2 O 5 , contributes to the superior localized corrosion resistance. The precipitation strengthening brought about by coherent L1 2 particles and the multi-stage plastic deformation dominated by stacking faults (SFs) provides ultrahigh strength and appreciable ductility, respectively. [Display omitted] • A novel corrosion-resistant L1 2 -strengthened HEA with high strength and ductility has been designed. • Ni, Al, and Nb are assigned to the L1 2 particles, while Co and Cr are left in the FCC matrix. • The oxide film enriched in Cr 2 O 3 and Nb 2 O 5 endows the HEA with high resistance to localized corrosion. • Ordering strengthening by coherent L1 2 precipitates and deformation-induced stacking faults provide an exceptional strength-ductility synergy. [ABSTRACT FROM AUTHOR]

• A shrimp content of 21.85% shortened development and increased larval survival. • A pollen content of 4.86% improved survival and pupation rates. • A lard content of 3.03% shortened the larval development period and increased survival and pupation rates. • The biological indices of larvae were optimal when the honey content was 10.02%. • The improved diet reduced developmental time and increased survival and pupation rates. The seven-spotted ladybird beetle, Coccinella septempunctata , is an important predator of soft-bodied insect pests that can be reared on both natural and artificial diets. In this study, an artificial diet for larvae was optimized by using a four-factor and three-level orthogonal design. Shrimp, pollen, lard, and honey were selected as the four key factors, and their effects on larval survival, development, and pupation were assessed. The results showed that an increased shrimp content of 21.85% in the diet could shorten developmental time and increase larval survival. Increased pollen content of 4.86% improved both pupation and survival, and a lard content of 3.03% shortened developmental time and increased survival and pupation success. The biological indices of ladybird larvae were optimal when honey content was 10.02%. [ABSTRACT FROM AUTHOR]

As the high temperature superconductors are under the electromagnetic field, large Lorentz body force can lead to the cracking of the superconductors. In the present paper, the dynamic fracture behavior of the crack in the bulk superconductor is investigated. We consider the central crack case and edge crack case. It is assumed that bulk superconductor is long enough and the demagnetization effect is neglected. By using the nonlinear constitutive relation in superconductor, the time-dependent Lorentz body force can be obtained. Then, the dynamic strain energy release rates are presented as the superconductor is under the magnetic field or with transport current. The results show that the dynamic strain energy release rates are also the periodic functions of time. The variations of dynamic strain energy release rate with edge crack length are different for the magnetic field and transport current cases. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mg and metallic glass hybrid materials were fabricated by selective laser melting. • Microstructure of Mg and metallic glass layers interface has been discussed. • Corrosion and wear resistance performance of Mg were improved by metallic glass. • Fe-based metallic glass has good wettability and is not toxic to the cells. Pure magnesium (Mg) is widely used as biomedical material, but its degradation rate is often too high and problematic to clinic applications. In this study, selective laser melting (SLM) was used to prepare an Fe-based metallic glass surface on a pure Mg substrate, forming a hybrid material to explore the advantage associated with such designed structure. It was found that the corrosion resistance was significantly improved with the hybrid material (from 0.89 ± 0.1 mm/a to 0.11 ± 0.03 mm/a in simulated body fluid), along with much increased hardness from 0.46 GPa to 14.3 GPa. The metallic glass surface was shown to retain its amorphous nature after the SLM processing. The molten pool formed by the applied laser beam resulted in a good mechanically interlocked bonding between the metallic glass layer and the Mg matrix. It was further revealed that the metallic glass surface had better wetting property than the Mg substrate, explaining why the MG-63 cells had good adhesion to it. The cell toxicity test was followed under the in vitro condition, indicating no toxicity in the metallic glass part. The results provide a feasible way to develop advanced Mg materials for biomedical applications via the capable SLM technology and via the suggested hybrid material. [ABSTRACT FROM AUTHOR]

• The printability of pre-alloyed Ti-45Al-8Nb alloy with yttrium addition has dramatically improved. • The introduced Y improves powders' oxidation resistance and laser absorption rate by surface structure altered. • High-Nb containing TiAl samples with high relative density and free of macrocracks were successfully prepared. • Modification of powder by rare earth elements can effectively improve the formability of crack-sensitive materials. [Display omitted] High Nb-TiAl alloys are important materials to realize critical, light-weight parts of high-temperature applications. It has been challenging, however, to realize their laser-based additive manufacturing (AM) due to the materials' high crack sensitivity. To mitigate the cracking problem particularly relating to oxygen, this study is designed to investigate the impact of introduced rare earth element (Y) on the microstructure, surface chemistry, and laser absorptivity of gas-atomized Ti-45Al-8Nb powder, and consequently on the printability of the alloy regarding its selective laser melting (SLM). It is observed that the Y addition significantly improves the SLM printability of the alloy and realizes samples that are free of macrocracks. The change in the surface structure of the powder is regarded as a critical factor contributing to improved printability. The corresponding chemical state and layer thickness of the oxide film covering the powder are determined by X-ray photoelectron spectroscopy (XPS) depth profile and transmission electron microscopy (TEM). It is further found that the surface structure of the powder leads to a higher laser absorption. As suggested by the study, modification of powder chemistry and powder surface structure by rare earth elements can be an effective means to improve the SLM formability of crack-sensitive materials. [ABSTRACT FROM AUTHOR]

Ultrafine silicon carbide (SiC) powders were surface-modified using ethyl orthosilicate (TEOS) combined with ethylene glycol. SiC suspensions with favorable rheological properties, low viscosity, and high solid loading were successfully obtained. The mechanisms of the compound surface modification for SiC powders as well as the influences of the compound surface modification not only on functional groups and charge state of the surface for SiC powders but also on the rheological properties of SiC suspensions were investigated in the present study. The results show that under alkaline conditions and acidic conditions, the surface charge states of SiC powders were [Si-OCH2CH2O]−and [Si-OCH2CH2OH2]+, respectively. The absolute value of zeta potential reached the maximum value of 22.69 mV at pH 11. Additionally, with added 1 wt% TEOS and 3 wt% ethylene glycol, the SiC suspensions exhibited good rheological properties, low viscosity and high stability due to the steric hindrance and electrostatic repulsion offered by the [Si-OCH2CH2O]-with a high concentration. [ABSTRACT FROM PUBLISHER]

Abstract: There are increasing demands for EOP predictions in science, deep space navigation, etc. Based on previous research on short-term prediction of Earth Orientation Parameters (EOP) by artificial neural networks (ANN), we extend our attempt to long-term predictions of EOPs, i.e. predictions with a lead time up to 360 days. The basic theory and some special considerations for the ANN forecast of EOPs are presented, and finally our preliminary results and their accuracy estimates are shown and compared with those obtained by other authors. [Copyright &y& Elsevier]

Abstract: We estimate geophysical excitations (χ1 and χ2) of polar motion using multiple sources of data, including recent atmospheric, oceanic, and hydrological models, satellite gravity measurements from the Gravity Recovery and Climate Experiment (GRACE), and compare geophysical excitations with observed polar motion excitations from space geodetic techniques. At seasonal time scales, both model-estimated excitations from the geophysical fluids envelope (i.e., atmosphere, ocean, and hydrosphere) and GRACE-observed excitations agree remarkably well with polar motion observations in the χ2 component, and in the χ1 component, model estimates and observed geodetic excitations show significant discrepancies. However, mass excitations estimated from GRACE show significantly better agreement with observed excitations than those from models, especially in χ1, due to better quantification of terrestrial water storage and oceanic mass changes using GRACE data. Furthermore, GRACE satellite gravity measurements offer a unique means for quantifying contributions from cryospheric angular momentum (CAM) change, a component mostly neglected in previous studies due to the lack of adequate observations or reliable ice sheets models. Based on GRACE estimates, CAM excitations appear a minor, but not negligible contributor to seasonal excitations of polar motion. The significantly better agreement in χ2 (than that in χ1) between observations and model excitations is related to the higher sensitivity of χ2 excitations to atmospheric pressure and terrestrial water changes over the Eurasia and North American continents, because of the special relationship between the ΔS21 spherical harmonic coefficient (proportional to χ2) mass model and the locations of the two continents. [Copyright &y& Elsevier]

Abstract: Sialon–Si3N4 graded nano-composite ceramic tool materials with five-layered symmetrical distribution were fabricated by using hot pressing technique. Mechanical property tests have been conducted to determine the optimal structural parameters and sintering parameters. The residual stresses in the surface layer of the graded ceramic tool materials were calculated by the indentation method. The experiment results showed that Sialon–Si3N4 graded ceramic tool materials with a thickness ratio of 0.3, which were sintered under a pressure of 35MPa at a sintering temperature of 1700–1750°C for 60min, had optimum mechanical properties. And the graded structure can induce residual compressive stresses in the material surface layer. The characterization revealed a typical duplex distribution with small β-Si3N4 grains embedded in the matrix of large β-Si3N4 grains. This duplex microstructure can contribute to the improvement of flexural strength and fracture toughness. Additionally, a mix of intergranular and transgranular fracture, crack deflection and crack bridging in the material surface layer contributed to the strengthening and toughening mechanisms for Sialon–Si3N4 graded ceramic tool materials. [Copyright &y& Elsevier]

Abstract: Co–24.0at.% Sn eutectic alloy melt was undercooled to different degrees below the equilibrium eutectic temperature. The dependence of solidification behavior on undercooling was established based on the experimental results of the solidification microstructure, crystal orientation and crystal growth velocity. In the entire undercooling range studied (0–203K), coupled eutectic growth of the α-Co and β-Co3Sn2 phases invariably takes place during the rapid solidification stage. The eutectic solidification interface advances in the alloy melt in seaweed morphologies rather than the well-known dendritic mode due to the weak interface energy anisotropy. But a critical undercooling of 175K exists, from which the eutectic solidification interface changes from a fractal into a compact seaweed pattern, accompanied with an abrupt increase of growth velocity. At high undercoolings the enhancement of the interface tip stability with the rise of crystal growth velocity should be responsible for the growth mode transition. [Copyright &y& Elsevier]

Abstract: A theoretical model for lamellar eutectic growth in undercooled eutectic alloy melts with a third element has been developed; it was assumed that no other phase forms. It is found that the tip radius of eutectic dendrite decreases with increasing content of the third element so as to diffuse away its enriched atoms ahead of the solidifying interface easily. A critical content exists below which the eutectic growth is accelerated within a certain undercooling range due to the third element addition, but slowed down otherwise. When more of the third element is contained, the growth velocity is always reduced. However, the eutectic lamellar spacing varies with the content in an opposite way. The influence of the third element addition is enhanced when the difference in distribution coefficients of the third element in two eutectic phases becomes greater. [Copyright &y& Elsevier]

Bulk Cu47.5Zr47.5Al5 metallic glass was rolled at different strain rates and temperatures. No phase transformation occurs in the as-rolled specimens except for shear bands. Free volume monotonously increases with increasing strain, and the rate of increase becomes larger with increasing strain rate or decreasing temperature. However, after an initial rise, the microhardness drops when the strain exceeds a critical value dependent on the rolling conditions. The increase in hardness is proved to result from the interaction of shear bands. [Copyright &y& Elsevier]

Abstract: Two bulk Ni–Pd alloys Ni75Pd25 and Ni54.8Pd45.2 have been undercooled beyond their hypercooling limits. As undercooling increases, two grain refinements, occurring at low and high undercooling, respectively, were observed in the solidification of both alloys, even though the equilibrium crystallization temperature range of the latter is only 5K. Reaching of the hypercooling limit did not change the microstructural morphology abruptly, and dendritic substructure could still be found in the refined grains. Such experimental results cannot be interpreted satisfactorily by the theory that the break-up of dendrites during solidification is dominated by capillary force. It is proposed that the grain refinement at low undercooling results from the remelting associated with chemical superheating, but that at high undercooling is due to the post-solidification recrystallization. [Copyright &y& Elsevier]

Abstract: The phase formation and crystallization kinetics during the thermal treatment of amorphous Zr60Al15Ni25 alloy were investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). By lowering the isothermal annealing temperatures, it is revealed that the crystallization of the amorphous Zr60Al15Ni25 alloy consists of a primary transformation followed by a polymorphic transformation, corresponding to the precipitations of hexagonal Zr6Al2Ni and the Zr5AlNi4 with a U3Si2-typed superstructure. The primary phase being Zr6Al2Ni rather than Zr5AlNi4 in the crystallization is because the latter has a complex structure and its formation requires the diffusion of Al and Zr atoms on a large scale. [Copyright &y& Elsevier]

Abstract: Ni54.6Pd45.4, a solid solution alloy without crystallization temperature range, has been undercooled by glass flux method up to the hypercooling limit. It was found that it solidified as pure metals. As undercooling increases, the secondary dendrite arm spacing decreases monotonously until a undercooling of 135K, above which the secondary branches considerably degenerate. The solidification with undercoolings higher than 160K leads to grain-refined structures. In this case, their average grain sizes continuously decrease with increasing undercooling even if the alloy has been hypercooled. The fact that grain refinement still takes place in the solidification of the hypercooled alloy indicates that the solidification time after recalescence is not a factor to dominate the grain refinement at large undercooling. Recrystallization of the solid in the post-solidification period should be responsible for the grain refinement. [Copyright &y& Elsevier]

Abstract: Polyanthra[1,9,8-b,c,d,e][4,10,5-b,c,d,e]bis-[1,6,6a(6a-S)trithia]pentalene (PABTP) was prepared and investigated as cathode active material for lithium secondary batteries. The organic disulfide polymer was prepared by the direct sulfurization of anthracene and the oxidative coupling polymerization of the sulfide anthracene, characterized by FT-IR, Raman, elemental analysis, XPS and XRD. The polymer was used as cathode active material and the lithium secondary batteries were assembled and tested. The polymer had high specific capacity up to 1500mAhg−1, which remained the value of 800mAhg−1 at the 77th cycle, and kept high charge–discharge efficiency of 85% in the whole test. [Copyright &y& Elsevier]

Abstract: Bulk Cu60Zr20Ti20 metallic glass has been rolled at room temperature (RT) and cryogenic temperature (CT) up to 97% in thickness reduction, and the dependences of microstructure on the strain and temperature have been investigated. It is revealed that as the deformation proceeds below a critical thickness reduction, which is 87% at RT and 89% at CT, only the shear band density and the free-volume content increase, whereas the thermal stability of the deformed glass remains unchanged. Deformation above the critical thickness reduction results in phase separation plus nanocrystallization at RT, but only phase separation at CT, indicating that lowering the temperature can effectively retard the deformation-driven crystallization, and that phase separation is the precursor of crystallization. The appearances of phase separation and especially nanocrystallization reduce the thermal stability of the glass since they create advantages in chemical composition and topological structure for the primary crystalline phase to nucleate and grow. [Copyright &y& Elsevier]

Thin film phosphors with compositions of RP1−xVxO4: A (R=Y, Gd, La; A=Sm3+, Er3+; x=0, 0.5, 1) have been prepared by a Pechini sol–gel process. X-Ray diffraction, atomic force microscopy (AFM), photoluminescence excitation and emission spectra were utilized to characterize the thin film phosphors. The results of XRD showed that a solid solution formed in YVxP1−xO4: A film series from x=0 to x=1 with zircon structure, which also held for GdVO4: A film. However, LaVO4: A film crystallized with a different structure, monazite. AFM study revealed that the phosphor films consisted of homogeneous particles ranging from 90 to 400 nm depending on the compositions. Upon short ultraviolet excitation, the films exhibit the characteristic Sm3+ 4G5/2–6HJ (J=5/2, 7/2, 9/2) emission in the red region and Er3+ 2H11/2, 4S3/2–4I15/2 emission in the green region, respectively. With the increase of x values in YVxP1−xO4: Sm3+ (Er3+) films, the emission intensity of Sm3+ (Er3+) increases due to the increase of energy transfer probability from VO43− to Sm3+ (Er3+). Due to the structural effects, the Sm3+ (Er3+) shows similar spectral properties in YVO4 and GdVO4 films, which are much different from those in LaVO4 film. [Copyright &y& Elsevier]

Summary: Background: Pemphigus is a group of rare life‐threatening mucocutaneous autoimmune diseases, presenting mainly as two subtypes: pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Inherited predispositions to pemphigus have long been speculated but they remain poorly understood. Objectives: To identify common and specific nongenetic and genetic factors associated with pemphigus and its subtypes in the Chinese population. Methods: A genome‐wide association study (GWAS) was performed in 496 unrelated patients with pemphigus (including 365 with PV and 104 with PF) and 1105 controls without pemphigus. Results: A sex preference was observed only in PV (57·5% female) and not in PF (47·1% female). For male patients only, the mean age at diagnosis was significantly lower for PV than for PF (P < 0·001). The strongest associated single‐nucleotide polymorphisms are in the human leucocyte antigen (HLA) region: rs70993900 (PV; P = 1·5 × 10−45) and rs9469220 (PF; P = 1·1 × 10−8). HLA‐DQB1*05:03 ranks at the top (P = 4·7 × 10−40; odds ratio 12·4) in both subtypes, with significantly different risk allele frequency (RAFPV = 34·2% vs. RAFPF = 18·8% vs. RAFcontrol = 4·4%), whereas HLA‐DRB1*14:01 and HLA‐DRB1*04:06 are PV specific. HLA‐DQB1*03:03 and HLA‐DQB1*03:02 show significant subtype specificity in opposite directions. All of these associations were validated in the replication series with 147 cases of pemphigus and 604 controls. Multiple novel non‐HLA susceptibility loci were also identified in the GWAS. Conclusions: This study represents the largest GWAS on pemphigus in the Chinese population published to date, and has allowed us to identify HLA haplotypes significantly shared between or specific to the two main subtypes of pemphigus. What's already known about this topic? Pemphigus is a group of autoimmune mucocutaneous diseases.It has multiple subtypes associated with certain human leucocyte antigen (HLA) haplotypes in an ethnicity‐specific manner. What does this study add? This is the largest genome‐wide association study published on pemphigus to date.We identified, for the first time, more than 100 single‐nucleotide polymorphisms (SNPs; six independent) at the HLA locus, with associations reaching genome‐wide significance.Some of these SNPs are strongly associated with specific subtypes of pemphigus. What is the translational message? The identified new haplotypes can potentially serve as genetic markers to improve investigation of the epidemiology and pathogenesis of pemphigus and its specific subtypes. Linked Comment:Geller. Br J Dermatol 2019; 180:713–714. Respond to this article [ABSTRACT FROM AUTHOR]