Niobium alloy has attracted widespread attention in the aerospace industry due to its high strength, excellent weldability and formability. It is capable of producing structural thin plates and complex shaped parts by laser directed energy deposition (LDED). In this work, single-track Nb-37Ti-5Al samples were fabricated by LDED to optimize of processing parameters, then multi-track Nb-37Ti-5Al was

The study investigates the effects of intensive shear strain processing, performed by selected regimes of rotary swaging, on recrystallization kinetics and deformation behaviour of a WNiCo tungsten heavy alloy. The results of uniaxial hot compression tests and thorough microstructure observations indicate that the selected rotary swaging regime, especially the swaging temperature, influences significantly

Austenitic stainless steels face multiple challenges during machining, including poor workability, severe tool wear, and unfavorable surface quality. Considering the machining issues resulting from poor tool-chip contact conditions, novel restricted contact tools with variable tool-chip contact lengths were developed to enhance machining performance. In this study, a systematic analysis was conducted

This paper proposes a short-process, environmentally friendly approach for preparing spherical tungsten oxide powder using peroxotungstic acid solution, and investigates the factors influencing the spray pyrolysis, as well as the underlying pyrolysis mechanism. The experimental results demonstrate that varying the concentration of peroxotungstic acid did not significantly affect droplet atomization

To develop high-temperature anti-wear performance nickel-based composites, Inconel 625 (IN625), vanadium (V), and graphene nanoplatelets (GNPs) are mixed based on the principle of in-situ generation. IN625 and IN625 metal matrix composite (MMC) coatings with x V/GNPs (x = 4, 8, 12) were then prepared using Laser Direct Energy Deposition (LDED). The effects of V and GNPs on the microstructure, microhardness

In this work we investigate the development of functionally graded cemented carbides, featuring macro gradients on the millimeter scale, where Fe, or Ni is the binder phase. Two composites, WC-Ni and WC-Fe with 20 % binder by volume were produced by addition of TiC on the surface of the samples before sintering at 1475 °C for 1 h. The sintered samples were analyzed using electron microscopy and microanalysis

The intensifying global climate threat is predominantly fueled by carbon dioxide (CO2) emissions from human activities. Although traditional carbon capture methods have advanced, they face significant challenges including high energy demands and secondary pollution risks, thus limiting their scalability. This study proposes a novel approach that integrates CO2 capture with molten salt electrolysis

In this paper, the effects of 1300 °C/30 h heat treatment on the microstructure and fracture behavior of Nb-16Si-20Zr-xm (xm=0, 4Cr, 2C, 4Hf, 4Ta, 0.5Sc) alloys were studied. Except for Nb-16Si-20Zr-2C alloy, the transformation from γNb5Si3 phase to αNb5Si3 phase occurs in other Nb-Si-Zr based alloys after heat treatment. There is a small amount of ZrC phase exists in the Nb-16Si-20Zr-2C alloy. After

Hard nitride coatings have the potential to serve as protective layers for cutting tools due to their excellent mechanical properties and wear resistance. To improve their mechanical, tribological, and high-temperature oxidation characteristics, the structural design of the coating is crucial. This study explores the micromechanical and tribological properties of multilayer WN/TiSiN and monolayer WN

By employing a liquid-liquid doping method to introduce Y2O3 and VC into WC-Co composite powders, WC-10Co cemented carbide with uniform microstructure and excellent performance was successfully prepared through low-pressure sintering. The effects of Y2O3, VC, and their composite addition on the microstructure and mechanical properties of WC-10Co cemented carbide were investigated. The results indicate

Functionally graded (FG) thin wall structures of B4C-AISI 434 L SS composite have been fabricated using three different B4C gradient strategies (namely smooth, moderate, and steep) by Tungsten Inert Gas aided Powder Bed Fusion Arc Additive Manufacturing (TIG PBF-AAM) method. For all different strategies, towards the building direction, substantial variations in the grain structure, phase composition

Agglomerated diamond (AD) abrasives have been proven applicable in the machinability of polyurethane lapping discs. However, the processing performance, material removal behaviour, and self-sharpening mechanisms of AD abrasives on lapping discs with different surface structures remain unclear. Therefore, in this study, we designed different groove-structured lapping discs and combined them with AD

Boron (B)-containing AlCrBN coatings are promising protective coatings for high-speed dry cutting application. In this work, AlCrBN coatings with various B contents (0 at.%, 2.9 at.%, and 4.8 at.% namely B0, B1, and B2) were synthesized, and their high-temperature and high-speed dry cutting performance were evaluated by the high-temperature vacuum annealing and high-speed dry cutting experiment. Comparing

Tungsten is a refractory metal with high density and is widely used in aerospace, medical, and nuclear applications due to its robust performance characteristics. In this study, 91 W-6.3Ni-2.7Fe alloys were fabricated via Selective Laser Melting (SLM). This study delves into the impacts of scanning speed on the densification, microstructure, and mechanical properties of the 91 W-6.3Ni-2.7Fe alloy under

In this work, we have realized a comprehensive assessment of the physical properties of MB (M = Ta, Nb, W) monoborides by conducting ab initio pseudopotential calculations based on the density functional theory with its generalized gradient approximation. According to their electronic density of states, the d-orbitals of transition metal atoms contribute most to the electronic bands of the studied

This paper studies the effect of Ti combined with different non-metallic sintering additives (Y2O3, ZrO2, TiO2, SiC) on the microstructure and mechanical properties of pressureless sintered B4C. B4C ceramics were successfully prepared by pressureless sintering at 2000 °C. The phase composition, microstructure and mechanical properties of the samples were analyzed. The results indicate that different

Improving the poor plasticity and fracture toughness of molybdenum alloys is the key to expanding their industrial applications. In this experiment, a cerium partially stabilized zirconia (Ce-PSZ) reinforced molybdenum alloy with outstanding properties was obtained by combining the hydrothermal method and the powder metallurgy technology. This study investigated how varying Ce-PSZ content influences

In this study, two types of tantalum powders were deposited using cold spray additive manufacturing (CSAM). We focused on comparing the effects of hydride-dehydride polygonal tantalum powder (A-Ta) and plasma-atomized spherical tantalum powder (STa) on the microstructure, mechanical properties, and tribological performance of the resulting deposits. Results revealed that under identical spraying conditions

In this study, AlMo0.5NbTiVSix (x = 0, 0.1, 0.2, 0.3, 0.4, and 0.5) refractory high-entropy alloys were fabricated by vacuum arc-melting, and the effects of Si on the oxidation resistance were systematically investigated. The results indicate that the oxidation behavior of alloys without Si addition primarily involved metal-gas interface reactions and solid-solution diffusion through the oxide layer

Transition metal W-P compounds with excellent mechanical and superconducting properties have attracted tremendous research interest. Herein, the mechanical, phonon, and superconducting properties of five W-P compounds are studied by first-principles and electron-phonon calculations. The phonon and elastic constants calculated results reveal that the five W-P compounds are dynamically and mechanically

In this research, an ammonia-free recycling method for tungsten scraps is proposed, involving the preliminary oxidation of waste tungsten carbide, reduction to intermediate-valence tungsten oxides, and subsequent dissolution in hydrogen peroxide to produce peroxotungstic acid (PTA), a valuable precursor for tungsten products. The study emphasizes stabilizing intermediate-valence tungsten oxides during

Surface quality can directly affect the hydrogen/helium retention behavior of tungsten, which will affect the safety and reliability of nuclear fusion reactors. At present, the polishing of polycrystalline tungsten for fusion reactors mainly has problems such as poor removal uniformity, preferential removal of grain boundaries, and processing defects. In this paper, a novel liquid film shearing polishing

TZM-ZrC composites with different particle content were produced by high-energy ball milling and discharge plasma sintering technology. The density, microstructure and phase composition of the composites with different particle content were investigated. The microhardness and compressive strength at room and high temperature were tested. The strengthening mechanism was explored. The grain size and

In this study, a zirconium sheet was fabricated utilizing laser directed energy deposition (L-DED) technique along with its microstructure, hardness, and wear resistance to be compared with a conventionally rolled and annealed (RA) zirconium sheet. The RA specimen exhibits equiaxed grains with uniform size and a bimodal basal texture, along with a few dispersed ZrFe2 particles. In contrast, the L-DED

The novel graded cemented carbides, with continuous variations in composition and phase, offers distinct functionalities to the surface and core. In the present work, a novel nitrogen-induced graded model cemented carbides with γ'-strengthened binder phase was systematically studied. Under the guidance of thermal analysis, the WC-Co-Ni-AlN-MC (M = Ta, Nb) graded model cemented carbides were sintered

W-Fe-B ternary system with different composition ratio were fabricated the pressureless sintering method. Effects of different original powder content on the mechanical properties of the alloy at different W/B ratios were systematically investigated. The results showed that the density varies with the proportion of elements and raw materials in the alloy. W2FeB2 hard particles size, hardness, compressive

Diamond reinforced WC based cemented carbide shows potential for hardbanding applications, with its performance hinging on the matrix's toughness, strength, and diamond holding ability. However, a comprehensive theoretical understanding of enhancing mechanical properties and controlling microstructure during pressureless infiltration remains limited. In this study, WC based cemented carbide was fabricated

The potential of refractory high entropy alloys (RHEAs) as high-temperature structural materials depends on optimising their oxidation resistance. This study examines the surface and cross-sectional oxide layers of TiNbTaVW RHEA after five hours of oxidation, comparing them to previously studied layers formed after 15 h. At 850°C, the surface and cross-sectional oxide layers remained crack-free after

In order to understand the mechanical, thermal and chemical properties of ultra-high temperature materials, which are crucial for the extreme environment applications, the valence electron density based temperature-dependent properties of ultra-high temperature (Ti1-xNbx)C have been investigated in this study. The obtained results demonstrated that the temperature-dependent work function, thermionic

The inversion of room-temperature compression plasticity and high-temperature strength in refractory high-entropy alloys poses a significant challenge for practical applications. In this study, a carbide-reinforced Ta-W-based refractory medium-entropy alloy was fabricated using spark plasma sintering. The alloy exhibits outstanding room-temperature compression plasticity and excellent high-temperature

In this study, two different compositions of WC-Co composite with gradient microstructure are designed and manufactured with the average cobalt content of 10 wt% and 8 wt% individually. Microstructure analysis and EDS test results confirmed the existence of a gradient distribution of cobalt content in the manufactured WC-Co composite. Mechanical properties including abrasive wear resistance, fracture

The present study involved the design and fabrication of a TiC-based ceramic bound by Fe-25Co-15Mo precipitation hardened steel using SLPS and HIP procedures. The microstructure and mechanical properties of the ceramic with different sintering temperature and heat treatment process were studied. The results show that the addition of 30 % TiC particles can not only form a typical core-rim structure

Refractory high-entropy alloys (RHEAs) are promising energetic structural materials (ESMs) owing to their high energy density and rapid energy release. Herein, an as-cast WTaTiCrV RHEA was prepared and its physicochemical parameters were studied to infer the phase stability. The dynamic compressive mechanical properties of the as-cast WTaTiCrV RHEA were investigated to evaluate its potential for application

In this study, the microstructure and mechanical properties of electron beam welded dissimilar joint of Nb to 304 austenitic stainless steel were analyzed. The results showed that the joint obtained were asymmetric due to the large difference in physical properties between the Nb and the 304 austenitic stainless steel. The weld mainly consisted of eutectic structure and brittle intermetallic compounds

TiCN-based, non-flat-layer ceramics with a novel inner structure comprising trapezoidal tooth layers were designed and fabricated by vacuum hot pressing sintering technology. The effects of the tooth number (TN) on the mechanical properties were studied. The results exhibited a trapezoidal tooth structure, consistent with the design. As a distinct characteristic, crack bridging in the TiCN–HfN (TH)

In this study, the Cu-Sn-Ti/Cu foam/Cu-Sn-Ti multi-layer composite fillers were designed to reduce the proportion of intermetallic compounds in YG18/Cu-Sn-Ti/40Cr joints, so as to modulate the microstructure and shear strength. The introduction of Cu foam effectively inhibited the Co solubilization in YG18 into the filler layer and reduced the content and proportion of intermetallic compounds such

New TiC based cermets have been obtained by liquid phase sintering using powder mixtures including Fe carbonyl, Mo2C, Cr3C2 and 17-4PH powders. As observed in other TiC-Fe based cermets, sintering of TiC-FeCrMo-17-4PH alloys involves the carbothermal reduction of powder oxides, which in the case of cermets containing 17-4PH, are mainly Cr and Ti based. Liquid phase sintering is hindered as the 17-4PH

Fully dense and fine-grained W2B5 ceramics were successfully fabricated by spark plasma sintering at 1375 °C using metallic cobalt as additive. Co reacted with W2B5 to form binary (CoB) and ternary phases (W3CoB3) during sintering process. Experimental results showed that the relative density of W2B5 ceramic increased from 96.7 % (for pure W2B5 ceramic sintered at 1800 °C) to 99.0 % with 10 wt% Co

The bonding of W and RAFM steel is of significance for the fabrication of plasma-facing components in nuclear fusion reactors. In this work, W and RAFM steel were bonded by using a two-step plated Cu interlayer to improve the performance of the W/Cu/RAFM steel joints. The bonding process contains two-step Cu plating on the W substrate followed by annealing, and subsequent diffusion bonding to RAFM

This study demonstrates the synthesis of a NbCxOy solid solution through carbothermic reduction and the subsequent extraction of metallic niobium through molten salt electrolysis. Thermodynamic analysis and carbothermic reduction were conducted to determine the optimal conditions for synthesizing the NbCxOy solid solution at different compositions, enabling precise control over their composition. Furthermore

Eutectic Nb-18.7Si alloys with different ceramic nanoparticle addition (Al2O3, TiC, SiC, 5 mol.-%), prepared by arc-melting, were heat-treated for 24 h at 1500 °C. Phase composition, microstructure transition and mechanical properties were investigated. The results show that the γ-Nb5Si3 and small Nb3Si phases from the as-cast alloy decomposed into α-Nb5Si3 and Nbss/α-Nb5Si3-eutectoids. Larger Nb3Si

This study was on whether cemented carbide tools could be produced using cheaper and more readily available Ni binder instead of expensive Co binder using selective laser melting, which is a new generation production method that can be easily produced in the desired design without losing scrap. The study determined the optimum laser manufacturing parameters for the production of Ni coated WC powder

The construction of intermediate layers in the diffusion bonding of cemented carbide and steel is an effective way to mitigate the difference in thermal expansion coefficients and reduce the induced residual stress (RS). However, additional pre- or post-treatment is crucial to further release the RS generated during bonding and enhance the performance of the joints. In this study, annealing and deep

In this study, finite element analysis software Marc was used for numerical simulation of electron beam welding of Ta2.5 W and then welding tests were carried out. The temperature change and equivalent stress distribution were analyzed and discussed during the welding simulation. When conducting welding experiments, welding beam and welding speed were adjusted based on the morphology of welded joints

The present study investigates the influence of nano-Y₂O₃ (0.25–0.75 wt%) additions on the microstructural evolution of a tungsten heavy alloy (WHA) composed of 93 wt% tungsten, with a fixed Ni/Co binder ratio of 9. The precursor powders of Ni, Co, and Y₂O₃ were subjected to high-energy ball milling to produce an oxide-dispersion-strengthened (ODS) matrix, which was subsequently blended with tungsten

The TiN ceramics, Ti-Cr-V-Zr-Nb-N composite ceramics, and (TiCrVZrNb)N high-entropy ceramics were fabricated by spark plasma sintering. The relationship between the microstructure, hardness, and wear resistance of these three ceramics were systematically studied, with emphasis on the solid particle erosion resistance of TiN ceramics and (TiCrVZrNb)N high-entropy ceramics. The results indicated that

The goal of this study was to explore the potential application of Cu-Ta-alloy shaped-charged jets to anti-armor operations, as well as to fill some of the research gaps in this field. The effects of composition ratios and microstructures on the penetration performance of CuTa jets were investigated. CuTa alloys with Ta concentrations of 20 wt% (Cu20Ta), 40 wt% (Cu40Ta), and 80 wt% (Cu80Ta) were prepared

This study investigates gradient cemented carbide with a cubic phase-free surface layer (CFL), commonly used as substrates for coated inserts to extend their service life. The tough gradient surface layer effectively prevents crack propagation, minimizing coating delamination and edge chipping. We propose using hexagonal boron nitride (h-BN) as a non-cubic nitrogen source for fabricating gradient cemented

Molybdenum (Mo) alloys, known for their exceptional physical and mechanical properties, find applications in aerospace, electronics, and medical fields. However, the high sintering temperatures and long processing times associated with their manufacturing lead to high-temperature furnace requirements and grain coarsening, negatively impacting their cost and mechanical properties. This study investigates

To address the challenges in joining immiscible W/Cu dissimilar metals, this study employs surface grinding to induce plastic deformation and coarsening on the W surface, thereby obtaining the reliable W/Cu joints through spark plasma sintering (SPS). The effects of surface grinding and bonding temperature on the interfacial microstructure, mechanical properties and thermal conductivity of W/Cu joints

Improving the mechanical properties of selective laser–melted pure tantalum (SLMed Ta), a new-generation orthopedic implant material, is of paramount importance. Appropriate annealing parameters directly affect the microstructure and macromechanical properties of SLMed Ta, thereby making them a focal point in the research on this material. This study conducted a gradient crossover experiment to elucidate

In this study, the effect of WC coating on the tribological performance of R260 rail steel was investigated by roller-on-plate wear tests and potentiodynamic polarisation corrosion tests carried out in dry and pure water environments. The High-Velocity Oxygen-Fuel (HVOF) method was used for the coating process. The tests were conducted with a weight of 40 N and a sliding speed of 0.03 m/s. An Ag/AgCl

TiB2-reinforced ultrafine Ti(C,N)-based cermets are fabricated via reactive spark plasma sintering. This study investigates the effect of carbon sources on the sintering processes, microstructures, and mechanical properties of cermets derived from a Co-Ni-Y-Ti-BN-WC-VC-Mo2C-TaC-C system. Results reveal that the sintering process involves both solid-state reactions and liquid-phase sintering stages

Numerous researchers are seeking methods to enhance the penetration power of tungsten alloy long-rod projectiles, and generating “self-sharpening” in the head of projectile core during penetration is an effective solution. Previous studies found that 88 wt% WC-Co (tungsten‑cobalt cemented carbides) alloy formed smaller ballistic holes compared to conventional 93 W alloy during high-speed penetration

Refractory high entropy alloys (RHEAs) are gaining widespread attention recently due to their excellent high-temperature properties. In this study, a WMoTaTi RHEA was fabricated by laser-based powder bed fusion of metals. The microstructure features with nanosized semi-coherent ductile face-centered cubic titanium (TiFCC) precipitates in the body-centered cubic (BCC) matrix. The oxygen enrichment and

Molybdenum components manufactured using Powder Bed Fusion-Laser Beam (PBF-LB) currently cannot achieve the mechanical properties and quality of powder-metallurgically produced parts. This is a result of the process characteristics of steep thermal gradients and high solidification rates in PBF-LB, which promote the development of a coarse-grained, columnar microstructure. It has been observed that

The high-temperature compressive properties of sintered W-10Re alloy were evaluated at temperatures of 1500–1600 °C and strain rates of 0.001–0.1 s−1. The experimental results obtained from flow stress analysis indicate that deformation is primarily governed by dynamic recovery (DRV), with dynamic recrystallization (DRX) also observed, particularly at a strain rate of 0.001 s−1. Within the safe processing

Mo14Re alloy is widely utilized in aerospace and nuclear energy applications due to its exceptional high-temperature mechanical properties and radiation resistance. Despite its significant high-temperature stability, the presence of pore defects seriously damages the mechanical properties of the alloy. This study combines crystal plasticity finite element simulation to reveal the influence mechanism

This study explores the innovative application of microwave hybrid heating (MHH) as a cost-effective and efficient method for fabricating advanced copper (Cu) powder-based metal matrix composites (MMCs). These composites are reinforced with tungsten (W) and molybdenum (Mo) powders at varying weight fractions (5 %, 10 %, and 15 %). The novelty of this research lies in the use of MHH, which combines

In this study, the effects of annealing temperature on the microstructure and mechanical properties of Al15Ti35V20Nb15Zr15 lightweight high-entropy alloy were systematically investigated. Results indicate that the Al15Ti35V20Nb15Zr15 alloy exhibits a dual-phase structure consisting of body-centered cubic (BCC) and hexagonal close-packed (HCP) phases. As the annealing temperature increases, the HCP