Rare Earth Research Articles

The Multiple Effects of RE Element Addition in Non-Oriented Silicon Steel

High-grade non-oriented silicon steel with high magnetic induction and low iron loss produced with low carbon emissions is crucial for the development of new energy and energy-saving motors. In this paper, the trace mixed rare earth (RE) elements exhibit a great potential to enhance magnetic properties in a lower carbon emission process by multiple effects on microstructure, texture, and inclusion in non-oriented silicon steel. With the trace-doped RE elements (0.004–0.030%), RE-rich precipitates preferentially form and subsequently adsorb fine inclusions below 1 μm to transform into spherical or ellipsoidal shape, which results in a significant increase in final recrystallization grain size. Moreover, the favorable λ texture (<001>//ND) is promoted while the detrimental γ texture (<111>//ND) is reduced, owing to the advantages in size and quantity of λ grains during the nucleation process. The improved magnetic properties of higher B50 and lower P15/50 are achieved with 0.004% RE at lower annealing temperature ranges. The increased λ texture is attributed to the heterogeneity in microstructure and texture as well as the grain boundary segregation of RE elements. However, a higher RE content (0.072%) leads to a deterioration in magnetic performance due to the formation of more stable RE-rich precipitates, smaller grains, and stronger γ texture. An iron loss calculation model was also proposed to guide the design of high-grade non-oriented silicon steel by incorporating the multiple effects of RE elements on grain size, recrystallization texture, and inclusion.

Tracing metal sources and groundwater flow paths in the Upper Animas River watershed using rare earth elements and stable isotopes

Groundwater flow paths and processes that govern metal mobility and transport are difficult to characterize in mountainous bedrock watersheds. Despite the difficulty in holistic characterization, conceptual understanding of subsurface hydrologic and geochemical processes is key to developing remediation plans for locations affected by acid mine drainage, such as the Upper Animas River watershed in southwestern Colorado, USA. Stable isotopes of water and rare earth elements were utilized to evaluate groundwater flow and metal sources within this complex catchment. Stable isotope samples collected from draining mine adits and springs display systematic spatial variation wherein sample sites at higher elevations have greater seasonal variability than sites at lower elevations. The Upper Cement Creek watershed, where multiple draining mines are present, displays the lowest seasonal variation in stable isotopic signatures, potentially indicating the presence of a large, well-mixed volume of groundwater storage or interbasin groundwater flow. Rare earth elements display statistically significant variation between different alteration styles in the catchment. Overprinting of regional propylitic alteration is evident based on enrichment of middle rare earth elements in acidic springs and mines that are not spatially associated with surficial exposures of acid generating alteration styles. Europium anomaly and middle rare earth enrichment signatures from two flooded mine tunnels on opposite sides of a watershed divide indicate connections to the same subsurface flooded mine workings.

Ultrasound-Assisted Extraction Followed by Inductively Coupled Plasma Mass Spectrometry and Multivariate Profiling of Rare Earth Elements in Coffee

A rapid and efficient ultrasound-assisted extraction (UAE) procedure followed by inductively coupled plasma mass spectrometry (ICP-MS) was developed for the determination of 14 rare earth elements (REEs) (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu), along with yttrium (Y) and scandium (Sc), in coffee samples. The method was validated using certified reference material (NIST SRM 1547), recovery tests at four fortification levels, and comparisons with microwave-assisted digestion (MAD). Excellent accuracy and precision were achieved, with recovery rates ranging from 80.1% to 112% and relative standard deviations (RSD%) below 14%. Limits of detection (LODs) ranged from 0.2 ng/kg (Yb) to 0.16 µg/kg (Nd). Total REE concentrations varied between 8.3 µg/kg and 1.1 mg/kg, with the highest individual mean concentrations (µg/kg) observed for Ce (11.7), La (6.0), and Sc (4.7). The lowest individual mean concentrations (µg/kg) were for Ho (0.16), Lu (0.066), and Tm (0.063). Multivariate analysis of REE profiles from 92 coffee samples collected in Serbia revealed clear distinctions between ground roasted and instant coffees, as well as between different surrogate blends. This study indicated that the determination of coffee’s geographical origin was not possible due to the diverse types, blends, and additives. However, differences in REE profiles suggest potential classification based on variety. REEs pose a negligible health risk to coffee consumers, with HI values ranging from 4.7 × 10−8 to 6.3 × 10−6 and TCR ranging from 2.6 × 10−14 to 3.5 × 10−12.

Are rare earth stocks efficient? Novel insights using asymmetric MF-DFA

This study investigates the weak-form efficiency and asymmetric multifractal scaling behavior of rare earth stock indices in the global, U.S. and Chinese markets during the trade war and the COVID-19 period. We examine the scaling behavior across overall, upward (bullish), and downward (bearish) market states from 2013 to 2021, employing an asymmetric multifractal detrended fluctuation analysis approach. Our findings indicate asymmetric multifractality in U.S. rare earth stock prices, caused by fat tails and long-range correlations. Weak-form price inefficiency and asymmetry in U.S. rare earth stock prices are prominent during market downturns, such as the trade war and COVID-19 periods. Chinese rare earth stocks demonstrate greater efficiency than U.S. and global stocks; thus, the latter markets provide arbitrage opportunities during upward and downward trends.

Rare Earth Metal Ion‐Doped Halide Solid Electrolytes plus Ta5+ Substitution for Long Cycling All‐Solid‐State Batteries

AbstractLi2ZrCl6 (LZC) solid electrolyte has been recognized as a promising candidate for all‐solid‐state batteries (ASSBs), owing to its remarkable compatibility with high‐voltage cathodes and the cost advantage among halide electrolytes. However, the ionic conductivity of LZC (≈0.4 mS cm−1) requires enhancement. Herein, rare earth metal elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Y) have been doped into LZC, resulting in a doubling of the ionic conductivity. Moreover, Ta5+ is utilized to further modulate the concentration of Li+ to enhance the ionic conductivity and reduce the dosage of expensive rare‐earth metal. Using the Li‐Zr‐Dy‐Cl component as a case study, 16 types of Dy3+ and Ta5+ co‐doped electrolytes have been synthesized and the optimal Li2.1Zr0.8Dy0.15Ta0.05Cl6 (LZDTC) exhibits the ionic conductivity of 1.67 mS cm−1. Three‐dimensional Li‐ion transport pathways in LZDTC has been revealed. The dual‐substitution of Dy and Ta at Zr site changes length of Li‐Cl bond and Li occupation, thereby reducing the resistance to Li+ migration. ASSBs of Li‐In/LGPS‐LZDTC/NCM811 demonstrate a capacity of 117 mA h g−1 after 500 cycle at 0.5 C with a 74% retention rate, highlighting the effectiveness of the dual‐doping strategy for creating superionic conductors for ASSBs.

Effect of Inherent Mg/Ti Interface Structure on Element Segregation and Bonding Behavior: An Ab Initio Study

To provide insight into the interface structure in Ti particle-reinforced Mg matrix composites, this study investigates the inherent Mg/Ti interface structure formed during the solidification of supercooled Mg melt on a (0001)Ti substrate using ab initio molecular dynamics (AIMD) simulations and density function theory (DFT) calculation. The resulting interface exhibits an orientation relationship of 0001Mg//0001Ti with a lattice mismatch of approximately 8%. Detailed characterizations reveal the occurrences of 0001Mg plane rotation and vacancy formation to overcome the lattice mismatch at the inherent Mg/Ti interface while allowing Mg atoms to occupy the energetically favorable hollow sites above the Ti atomic layer. The atomic diffusion behaviors of rare-earth elements Gd and Y at the Mg/Ti interface was examined using the climbing image nudged elastic band (CI-NEB) method, demonstrating a strong segregation tendency towards the interface promoted by the inherent interface structure. Additionally, the calculated Griffith work indicates enhanced interfacial adhesion due to the segregation of Gd and Y, which is beneficial for the mechanical properties of the composite.

Geochemical signatures and contamination levels of rare earth elements in soil profiles controlled by parent rock and soil properties.

Rare earth elements (REEs) are emerging contaminants rendering potential risks in soils to environmental quality and human health. The causation between their geochemical signatures and contamination levels with parent rocks and soil properties are critical for REEs risk assessments, which are urgently needed globally. Thus, this study aimed to elucidate cause-and-effect among hydrofluoric-acid-digested total and ethylenediaminetetraacetic acid extracted bioavailable soil REEs and their contamination degree evaluated by pollution indices in 268 soil layer (horizon) samples from 50 soil profiles derived from felsic, intermediate, mafic, ultramafic, and sedimentary rocks in Taiwan. The total REEs was 133 ± 61.9mg/kg and all individual REEs were classified as minimal contamination by the enrichment factor. The highest total soil REEs was from granite, followed by sandstone and shale, mafic rocks, andesite, and ultramafic rocks. All soils were ranked as significantly pollution risk by the pollution loading index. Furthermore, REEs were accumulated in all subsoils due to the co-translocation with soil colloids during the intensive leaching, corresponding with their higher geoaccumulation index value than those in surface soils. The contamination degree and bioavailable REEs significantly increased with the increasing total REEs. However, the stronger sequestration of clay and free Fe oxides for heavy REEs (HREEs) over light REEs (LREEs) mitigated their bioavailability, especially in the highly weathered soils like Ultisols and Oxisols. This study highlighted the dominance of soil properties in REEs fractionation, where the preferential fixation of soil colloids for HREEs throughout soil profiles reduced their uptake risk for biome even under the rising contamination potential.

Mining and industrial processing wastes of phosphate rocks in Egypt: potentiality of rare earth elements

Abstract Globally, Egypt ranked the eighth position in the production of phosphorus with about 5 million tons annually. Phosphate ore is considered one of the commonest sources of rare earth elements (REEs). Mining and industrial processes (beneficiation) of phosphate ore produce huge amounts of wastes in different sizes. The present study aims to evaluate the potentiality of the phosphate ore wastes as a source of rare earth elements (REEs). The study targeted some phosphate production sites in Egypt, including: Abu Tartur, West and East El-Sebaiya phosphate mines, in addition to the fertilizers factory in Assiut. The collected waste samples, during 2023, were analyzed in terms of mineralogical composition using XRD (X-Ray Diffraction) and chemical composition using XRF (X-Ray Fluorescence). The results of chemical analysis recorded the highest concentrations of Y, Ce, La, Nd, Sc, Sm, U, and Th in Abu Tartur waste samples, while the lowest concentrations were recorded in the fertilizers factory waste samples. These wastes contain higher concentrations of REEs than the Algerian and USA wastes. Furthermore, an enrichment of the mostly environmental hazardous elements As, Cr, Cd, Pb, and Se are detected in Abu Tartur and West and East El-Sebaiya. Thus, the wastes from the industry and mining processing of phosphate represented a vital economic source for the production of REEs. The use of wastes for production of trace and rare earth elements represents an economic and environmental add value for phosphate industry.

Research Progress of Cu-Ni-Si Series Alloys for Lead Frames

This paper reviews the research progress of Cu-Ni-Si alloy as a lead frame material for ICs. Cu-Ni-Si alloy is considered a strong candidate for lead frame materials due to its excellent mechanical properties and adequate electrical conductivity. The types and properties of Cu-Ni-Si alloys are then discussed in detail, emphasizing strength and conductivity as two key indicators for evaluating the properties of Cu-Ni-Si alloys, as well as the challenges posed by their inverse correlation. The preparation methods of Cu-Ni-Si alloy, including conventional melting, vacuum melting, and jet forming, are also discussed, and the effects of different casting techniques on the alloy’s properties are analyzed. Furthermore, the conductivity and strengthening mechanisms of Cu-Ni-Si alloy, including solid solution strengthening, second phase strengthening, and deformation strengthening, are discussed. The effects of the Ni-Si atomic ratio, trace elements, and rare earth elements on the alloy’s properties are also discussed. Finally, the current research status of Cu-Ni-Si alloy is summarized, and future research directions are identified, including the development of new preparation technologies, establishment of systematic databases, and promotion of green manufacturing and sustainable alloy development.

Porous Single-Crystalline Rare Earth Phosphates Monolith to Enhance Catalytic Activity and Durability

Rare earth phosphate (XPO4) is an extremely important rare earth compound. It can exhibit excellent activity and stability in catalytic applications by modifying its inherent properties. Porous single-crystalline (PSC) PrPO4 and SmPO4 with a large surface area consist of ordered lattices and disordered interconnected pores, resulting in activity similar to nanocrystals and stability resembling bulk crystals. Herein, we present a study in which centimeter-scale PSC PrPO4 and SmPO4 monoliths were developed and oxygen defects in the crystal lattice were stabilized using single-crystal nature to synergistically improve catalytic activity in the oxidative dehydrogenation of ethane (ODE). The surface structure of the oxygen vacancies with unsaturated coordination is favorable for the adsorption and activation of ethane. The PSC PrPO4 and SmPO4 monoliths showed favorable performance with ~51% conversion of C2H6 and ~19% yield of C2H4 at 600 °C, while also exhibiting superior long-term stability during the catalytic process over a period of 115 h. In the presented work, we investigate a practical method for development and application in single-crystalline porous rare earth phosphate materials.

Palaeoenvironmental implications and genesis of lacustrine Lower Triassic giant ooids

The sedimentary environment and mechanisms of formation of giant ooids (> 2 mm) are not well understood. Here, we use petrographical, mineralogical and geochemical data of giant ooids from the Lower Triassic Buntsandstein Formation of central Germany to develop a coherent formation model. Structural preservation of calcite crystallites in ooid cortices in combination with comparatively low strontium concentrations (< 545 μg/g) and the absence of dolomite in the cortex suggest a primary low-Mg calcite composition. Shale-normalised rare earth elements plus yttrium (REE + Y) patterns lack a pronounced heavy REE over light REE enrichment and show a positive cerium anomaly (Ce/Ce*SN = 1.9–3.9). Together with a missing yttrium anomaly and low Y/Ho ratios (< 40), these data are largely consistent with ooid formation in a lacustrine environment. Positive cerium and lanthanum anomalies further point to formation and deposition in an alkaline to hypersaline playa-lake environment. Based on our findings, a five-stage formation model is proposed. We suggest nucleus formation by microbial spheres, followed by calcite crystal nucleation on biofilm templates at the sediment–water interface, and crystal/cortex growth inside the sediment pile. The spherical ooid form is achieved by wave-induced physical rolling motion after exhumation. Ooid growth ceases when the ooid reaches a critical size (here 4 mm), depending on local hydrodynamic properties. Inhomogeneous crystal growth and the inclusion of exogenous particles lead to structural and geochemical anomalies in the ooid cortex. Results presented here have far-reaching implications for the application of REE and other trace elements as environmental proxies in ancient carbonates.

Scalable Synthesis of 2D ErOCl with Sub-meV Narrow Emissions at Telecom Band.

Van der Waals (vdWs) materials are promising candidates for hetero-integration with silicon photonics toward miniaturization and integration. VdWs materials like molybdenum telluride and black phosphorus, despite being prominent, exhibit air sensitivity, and their room temperature emissions can be significantly broadened by tens of meV. Here, a self-encapsulation strategy is developed to scalably synthesize robust 2D vdWs ErOCl with sub-meV narrow emissions at the telecom C-band. Diverse 2D rare earth materials are also grown via chemical vapor deposition (TmOCl, YbOCl, HoOCl, DyOCl, SmOCl, NdOCl, TbOCl, GdOCl, EuOCl, and PrOCl), demonstrating the strategy's generalizability. The as-grown ErOCl exhibits high crystalline quality and excellent ambientand thermal stability (300°C). Photoluminescence analysis reveals a series of narrow emissions across the visible to near-infrared spectrum. The ErOCl's emission at the telecom band is narrowest among 2D luminescent materials, and suitable for integrating with photonic chips. Temperature-dependent photoluminescence spectra facilitate the understanding of emission mechanisms, analyzed using a crystal field perturbation model. Moreover, these emissions can be tuned by external magnetic fields. This research not only pioneers a novel strategy for synthesizing 2D rare earth materials but also paves the way for innovative building blocks in the realm of on-chip optical communications.

Multi-Element Exposure and Health Risks of Grains from Ambagarh Chowki, Chhattisgarh, India

Rice, wheat, and maize grains are staple foods, widely consumed for their mineral and nutritional values. However, they can accumulate toxic elements from contaminated soils, posing health risks. This study investigates the bioaccumulation patterns of 52 elements (including nutrients, heavy metals, and rare earth elements) in various parts (grain, husk, straw, and root) of cereals grown in a heavily polluted region. The results revealed that rice grains exhibited a higher accumulation (Σ33.4 mg/kg) of toxic elements (As, Cu, Cr, Ni, and Pb) than wheat (Σ26.6 mg/kg) and maize (Σ16.2 mg/kg) grains, with the high-yield RI64 cultivar (Σ47.0 mg/kg) being the most susceptible. Across the rice plant, accumulation increased in the order of grain &lt; husk &lt; straw &lt; root. Elements like P, K, Cu, and Zn showed the highest enrichment. Worryingly, the most toxic elements, such as As, Pb, and Cd, exceeded permissible limits across grains, straws, and husks. Health risk assessment indicated that wheat and maize pose greater non-cancer and cancer risks than rice. Despite being grown in a highly contaminated region, the study identifies some rice cultivars like Luchai and Sarna as relatively safer options due to a lower accumulation of toxic elements.

Effect of Y on the Microstructures and Heat-Resistant Property of ZL109 Alloys

The effects of rare earth Y on the microstructures and tensile properties of ZL109 alloys were studied through metallographic observation, scanning electron microanalysis, X-ray diffraction, and tensile experiments, and the existence form and mechanism of Y were analyzed. The results show that the grain size of the ZL109 alloy is obviously reduced and that the strength of the ZL109 alloy is significantly increased after adding the Y element. When the Y content is increased to 0.2 wt.%, the tensile properties of the ZL109 alloy at room temperature and 350 °C are better than those without a rare earth addition, and the comprehensive tensile properties are better. This is due to the addition of the Y element; α-Al dendrites are obviously refined, and there is a tendency for them to change into fine isometric crystals. The size of the eutectic Si decreases, and its shape is modified. The morphology and size of high temperature enhanced phases, such as Al3CuNi, are optimized. The heat-resistant enhanced phase Al2Si2Y is formed after the addition of rare earth Y. However, with the addition of the Y element, the Al2Si2Y phase increases, and coarsening results in the decrease in alloy strength.

Crystal Structure and Magnetic Properties of the Novel Compound ErMn5Ge3

The RE-M-Ge systems (RE: rare earths, M: transition group elements) contain a large number of compounds with special magnetic properties. A novel compound ErMn5Ge3 was found during the investigation on the phase diagram of the Er-Mn-Ge ternary system, and its crystal structure and magnetic properties were investigated. Powder X-ray diffraction results show that ErMn5Ge3 crystallizes in an orthorhombic YNi5Si3-type structure with the space group Pnma (No. 62) and the lattice parameters of a = 13.0524(6) Å, b = 3.8853(7) Å, and c = 11.4027(4) Å. The magnetization curves and isothermal magnetization curves from 100 to 300 K were measured for ErMn5Ge3. Magnetic tests showed that the compound was weakly magnetic and had a Curie temperature of 304 K. It is believed that its magnetic properties are determined by Mn atoms, which are surrounded by a complex environment, leading to uncertainty in the direction of the magnetic moment and hence poor magnetic ordering. This uncertainty simultaneously leads to a significant separation of the ZFC and FZ curves. First-principles calculations confirm that the magnetic properties of ErMn5Ge3 are mainly provided by the Mn atoms, and its magnetic moment is calculated to be about 4.5 μB. A possible magnetic structure model with simultaneous Mn-Mn ferromagnetic/antiferromagnetic coupling is constructed based on the Mn atom spacing, which can well explain the magnetic performance of ErMn5Ge3.

Regulating Intermediate Adsorption and Promoting Charge Transfer of CoCr-LDHs by Ce Doping for Enhancing Electrooxidation of 5-Hydroxymethylfurfural.

Electrochemical oxidation of 5-hydroxymethylfurfural (HMFOR) to generate high-value chemicals under mild conditions acts as an energy-saving and sustainable strategy. However, it is still challenging to develop electrocatalysts with high efficiency and good durability. Here, nickel foam (NF) supported CoCrCe(7.5%)-LDH (layered double hydroxides) by doping Ce into CoCr-LDH show high 5-hydroxymethylfurfural (HMF)conversion (99%), 2,5-furandicarboxylic acid (FDCA) yield (99%), and Faraday efficiency (100%) at 1.4 VRHE. The CoCrCe(7.5%)-LDH also exhibits remarkable stability with 97% conversion of HMF after 10 cycles. The X-ray absorption near-edge spectroscopy (XANES) and theoretical calculation show that Ce doping into CoCr-LDH is beneficial to the formation of high-valance Co and significantly facilitates the electron transfer, regulates the adsorption behavior of intermediates, reduces the Gibbs free energy barrier and accelerates the reaction rate. This work promotes the use of rare earth elements as electrocatalysts to promote the oxidation of HMF.

Ammonia Decomposition Catalyzed by Co Nanoparticles Encapsulated in Rare Earth Oxide.

We fabricated Co-based catalysts by the low-temperature thermal decomposition of R-Co intermetallics (R = Y, La, or Ce) to reduce the temperature of ammonia cracking for hydrogen production. The catalysts synthesized are nanocomposites of Co/ROx with a metal-rich composition. In the Co13/LaO1.5 catalyst derived from LaCo13, Co nanoparticles of 10-30 nm size are enclosed by the LaO1.5 matrix. The nanocomposite exhibited superior catalytic activity (91% at 500 °C), which was attributed to dual advantages; the low workfunction of the supporter, O-deficient LaO1.5-x nanoparticles, promotes electron donation to the Co catalyst in the interface, which leads to enhanced N-H bond dissociation. Moreover, such a composite structure is effective in suppressing the grain growth of Co nanoparticles because the LaO1.5 layer works as a diffusion barrier against Co. The thermal decomposition of intermetallics is a new route for the facile synthesis of catalysts having an electronically active support.

Evaluating the bioavailability of rare earth elements in paddy soils and their uptake in rice grains for human health risk.

Rare earth elements (REEs) are a critical global focus due to their increasing use, raising concerns about their environmental distribution and human exposure, both vital to food safety and human health. Surface soil (0-30cm) and corresponding rice grain samples (n = 85) were collected from paddy fields in Taiwan. This study investigated the total REE contents in soil through aqua regia digestion, as well as their labile forms extracted using 0.05M ethylenediaminetetraacetic acid (EDTA), 0.10M hydrogen chloride (HCl), and 0.01M calcium chloride (CaCl2). The REE concentrations in the rice grains (Oryza sativa L.) were also analyzed. The estimated daily intake (EDI) of REEs through rice consumption for males was 1.3 times higher than that for females. Children under 12years of age, regardless of gender, had the highest EDI of REEs compared to other age groups. High rice consumption and a high proportion of children are potentially at higher risk for elevated REE exposure. The transport of REEs from soil to rice demonstrated their shift of fractionation by the lower ratio of light REEs and heavy REEs in rice grain compared to soil and their upper continental crust (UCC)-normalized patterns. Empirical equations were developed to estimate the concentrations of REEs in rice grains based on soil pH, clay content, organic carbon, cation exchange capacity, dithionite-citrate-bicarbonate extractable iron, and labile REEs. This study provides critical insights into the health risks of REEs, clarifying their human exposure and the bioavailability from paddy soil to rice.

Petrogenesis and Tectonic Setting of the Xishan Pluton in Nanling Range: Lithogeochemistry, Zircon U–Pb Chronology and Hf Isotope Evidence

ABSTRACTIn this article, a systematic LA‐ICP‐MS zircon U–Pb geochronology study was carried out on the Xishan pluton in Nanling Range. The results show that the formation ages of granitic porphyroclastic lava, medium‐fine‐grained porphyritic granite, and dacite are 154.0 ± 1.2–156.1 ± 2.0, 153.2 ± 0.9–157.3 ± 3.2, and 151.2 ± 3.1 Ma, which are determined to be the early Yanshanian. Geochemical data show that the Xishan pluton was characterised by rich silicone‐alkali and poor calcium–magnesium with K2O/Na2O ratios of 1.65–2.22, Al2O3 of 1.00–1.14, and FeO*/MgO ratios of 8.33–19.0 (with an average of 12.94). The rare earth content of granites ranges from 322.92 to 441.54 ppm, which is significantly higher than the world average. The rare earth element distribution curve is right‐leaning light rare earth enrichment type, with obvious negative europium anomaly, and the δEu values range from 0.06 to 0.24; These rocks are enriched in high‐field‐strength elements (HFSEs, e.g., Ga, Y, Nb, Zr, and Hf) and depleted elements such as Ba, Nd, Sr, P, Ti, etc, with Ga/Al ratios of 2.95 × 10−4 to 4.59 × 10−4 (with an average of 3.50 × 10−4); Zr + Nb + Ce + Y of 367.1–652.5 ppm (with an average of 441.95 ppm) and zircon saturation temperatures Tzr is 755.04°C–892.50°C (with an average of 810.04°C), similar to geochemical features of A‐type granites. The Hf isotope study shows that the εHf(t) of the Xishan pluton ranges from 2.11 to −8.77, and the petrographic, geochemical and available data confirm that it originates from the mixing of crustal and mantle‐derived magma, and the contribution of the latter is &lt; 10%. The hafnium II model age of the Xishan pluton is 1251–1766 Ma, which confirms that its source rocks were detached from the mantle reservoir at the time of the Middle Proterozoic. Combined with the evolutionary history of the Nanling Range area, it is assumed that the Jiangnan Orogenic Zone was partially reactivated by the continuous lateral subduction of the ancient Pacific Plate in the Late Mesozoic, which triggered partial melting of the crust to form the A2‐type granite type, which is the origin of the Xishan pluton.

Enhancing Ω Phase Thermal Stability in Al Alloys through Interstitial Ordering.

Scandium (Sc) can orderly occupy interstitial sites within the Ω phase of aluminum alloys, forming a new phase that significantly enhances the thermal stability of the alloy. However, Sc is relatively expensive and rare. In this work, we employ first-principles calculations to delve into the physical essence interstitial ordering of Sc in enhancing thermal stability at the electronic level, thereby revealing the crucial factors responsible for this improvement. By computationally screening all potential metallic elements across the periodic table, we uncover that, in addition to Sc, a diverse range of elements including lithium (Li), calcium (Ca), strontium (Sr), and some of rare earth elements (Sm, Ce, Y), possess the potential to contribute to thermal stability enhancement through interstitial ordering mechanisms in aluminum alloys. This study deepens our understanding of microstructural thermal stability and offers novel strategies for designing improved thermally stable Al alloys.