Molybdenum is highly valued in industry because of its unique properties, especially at high temperatures. Additive manufacturing technologies, particularly laser powder bed fusion (LPBF), are becoming increasingly popular for producing complex shapes at a lower cost as compared to the conventional forming processes. However, printing molybdenum with LPBF presents challenges, especially caused by its

In the work, the influences of water-vapor concentration and reaction temperature on the volatilization behavior of high-purity MoO3 in the range of 600 °C to 750 °C were investigated. Different technologies such as XRD, FESEM, and thermodynamic software FactSage 8.3, were adopted to analyze the experimental data. The results showed that the volatilization rate of high-purity MoO3 was increased with

Laser powder bed fusion (L-PBF) has been investigated as an additive manufacturing technique for the fabrication of WC-Co hardmetals, with limited success. This study investigates the link between critical

Surface texturing has proven to be an effective method for enhancing lubrication performance and is widely applied in tribology. The Tesla valve, with its unique geometric configuration, provides a novel paradigm for surface texture design. However, the mechanisms by which Tesla valve textures affect tribological behavior under water lubrication remain insufficiently explored. In this study, WC-10Co-4Cr

For purposes of revealing the frictional and wear mechanism of polycrystalline diamond (PCD) compacts under the working temperatures of 25, 50, 75,100, and 125 °C, the linear reciprocating mode of CSM-TRN model tribo-tester has been used to investigate the effect of working temperatures on tribological behaviors of PCD compacts under drilling fluid lubrication conditions. Experimental results show

This study investigates the refractory Nb-Mo-Ta-V alloy system, focusing on compositions that achieve a balance between tensile strength and ductility across a wide temperature range while maintaining decent formability. Four refractory complex concentrated alloys (RCCAs), Nb90Mo5Ta5 (in at.%), Nb85Mo5Ta5V5, Nb75Mo5Ta15V5, and Nb65Mo5Ta25V5, exhibited superior cold workability and formed single-phase

We have synthesized a series of alloys of the quaternary Co-Ti-Ta-Re system in the region of existence of the fcc cobalt solid solution. Heat treatment of the obtained samples included three stages: homogenization at 1375 K (100h), aging at 1200 K (24 h) and tempering at 1030 K (24 h). The microstructure and phase composition of the alloys were studied by scanning electron microscopy, local X-ray spectral

Ti(C, N)-based cermet is essentially a composite of Ti(C, N) hard ceramic phase embedded with metal binder phase. Due to their excellent high-temperature mechanical properties and wear/ oxidation resistances, they are widely used in metal machining. However, the mutually exclusive mechanical responses (hardness versus toughness, strength versus wear resistance, etc.) of traditional Ti(C, N)-based cermet

This study systematically investigates the friction and wear behavior of Ti2Zr0.75NbVx (x = 0.25, 0.5, 0.75, 1) lightweight refractory medium-entropy alloys (MEAs) and the underlying wear resistance enhancement mechanisms through a combined approach of experimental characterization and molecular dynamics (MD) simulations. The results reveal that atomic size mismatch-induced lattice distortion promotes

For the first time, the sessile drop method was applied to compare the high-temperature interactions of liquid Mg with dissimilar refractory substrates, including pure Ti, Nb, and a TiNb alloy (26 at.% Nb). A capillary purification procedure was employed to eliminate both the influence of heating history and the presence of native oxide films on the Mg samples.

VAl master alloys are essential raw materials for producing high-quality titanium alloys, which are generally produced by aluminothermic reduction, metal-slag gravitational separation method. The conventional way faces the challenges of excessively high reaction temperatures, metallic inclusions in slag, and difficulties in fabricating higher-Al-content alloy in one step. To conquer these issues, this

Refractory metal high-entropy nitride (RHEN) coatings have attracted significant attention for extreme environmental applications due to their outstanding mechanical properties. However, traditional trial-and-error methods for optimizing process parameters are inefficient and costly. To solve this limitation, this study proposes a stacking machine learning framework to predict the hardness and modulus

Thermally sprayed cermet coating has become a potential substitution for hard chrome plating as it possesses promising mechanical and tribological properties that are greatly pompous by the residual stress. The prospect of nanoindentation technique to assess the residual stress in WC-based coating is extremely limited. In the current investigation, a large number of nanoindentation experiments are

To mitigate the inherent brittleness of pure tungsten, strategic additions of relatively low-melting-point metals such as nickel (Ni) and iron (Fe) are typically incorporated to enhance the toughness of alloy. Laser additive manufacturing (LAM) technology presents a novel approach for fabricating complex-structured tungsten alloy components. However, a critical technical challenge emerges during the

Traditional cermets face challenges due to brittleness and temperature sensitivity. This study introduces a novel solid solution strengthening strategy, achieved through nanoparticle hybridization and optimization of sintering parameters, to develop binderless titanium carbonitride nanocomposites (BTC) with enhanced tribological and thermomechanical properties. By tailoring the dense microstructure

Tungsten (W), which possesses the highest melting point of any metal (3422 °C) and thermal stability and mechanical strength, is a material of choice for extremely demanding applications ranging from aerospace and nuclear fusion reactors to high-temperature manufacturing. However, tungsten's use in additive manufacturing processes is limited by its tendency to crack due to its high ductile-to-brittle

The interfacial microstructure and fracture behavior of tungsten alloy/steel joints bonded using an Nb/Ni composite interlayer were systematically investigated. Microstructural characterization and mechanical property evaluations confirmed the successful bonding of the joints. The Nb/Ni interface predominantly consisted of NbNi, NbNi3 and Nb4C3-x intermetallic compounds (IMCs), while the tungsten alloy/Nb

Detonation spraying of WC-12Co, WC-10Co4Cr and WC-12Ni coatings was performed on a CCDS2000 facility using explosive mixtures based on a two-component fuel, aС2Н2 + bС3Н6 + cО2. The coatings were formed on carbon steel substrates. The detonation gun barrels used for spraying were of three different configurations to produce tensile and compressive stresses as well as an unstressed state in the coatings

Additive Manufacturing (AM) of refractory alloys is gaining traction as a materials processing route for components subject to extreme temperature environments. Due to the low oxidation resistance of refractory alloys, novel methods for evaluating their elevated temperature performance must be developed. In this work, a Gleeble® 3800 thermomechanical load frame was modified to evaluate the mechanical

The unidirectional and bidirectional sliding tests for using Si3N4 ceramic as the grinding ball sliding with the circular motion against in situ formed TiCx/high Cr white iron composite (TiCx/HCWI) were performed to study the wear behaviors. The cyclic numbers CN = 0, 1, 2, 5, 10 were adopted to observe the friction coefficient, wear volume loss, roughness (Sa) and the height difference between the

The deposition of diamond coatings on cemented carbide (WC–Co) tool surfaces using chemical vapor deposition (CVD) is an effective method for improving tool life. However, it is necessary to perform a cobalt removal pretreatment on the WC–Co tools to mitigate the catalytic graphitization effect. In this study, a pretreatment process based on electrochemical selective dissolution is proposed. By controlling

An in-situ Ti-based metallic glass matrix composite Ti43Zr32Ni7Ta4Be14 (at. %), optimized via compositional refinement from Ti43Zr32Ni6Ta5Be14 (at. %), achieves more exceptional dynamic mechanical performance through twinning activation. This composite demonstrates enhanced yield strength (1712–1811 MPa) and plasticity (3.3 %) under dynamic loading (1000–1500/s), outperforming the one before optimizing

The effects of TiC and Cr7C3 contents on the mechanical and wear properties of carbide particles reinforced iron composites are investigated in the present work. Firstly, the Cr7C3–TiC–Fe composites designed from CALculation of PHAse Diagrams (CALPHAD) method were fabricated by the spark plasma sintering (SPS) process. Subsequently, their microstructure, hardness, and wear property were measured by

This article presents research results related to microstructural changes in modified flame-sprayed DURMAT 61-PTA (NiFeSiB + WC/W2C) coating by introducing additional Metco 15E (NiCrFeBSiC) sublayers into the coating system with next laser remelting. This modification aimed to increase the adhesion of the large, high-melting and hard tungsten carbides to the substrate material and to facilitate and

The design of tungsten (W)-coated fuel particles represents one of the pivotal strategies for enhancing the performance of cermet fuel. An intact W coating not only facilitates effective containment of fission products, enabling uniform dispersion of the fuel, but also effectively hinders the inward diffusion of the operating medium (H2), thereby reducing fuel loss. However, during the preparation

The global oil and gas exploration was towards deep and ultra-deep formations. The complex drilling environment of the deep formations put forward higher requirements on the performance of drill bit materials. As the most commonly used drill bit materials in oil drilling, the performance of polycrystalline diamond compact (PDC) directly affected the drilling efficiency, drilling quality and drilling

Multi-principal element alloys (MPEAs) based on refractory metals have been studied as potential candidates to replace Ni-based superalloys due to their superior melting temperatures and the promising initial high-temperature properties demonstrated by certain compositions. However, a significant drawback of these refractory metal-based alloys is their high density and low ductility at room temperature

In this work, the influence of chloride and sulfate ions on the corrosion behavior of WC-Co and WC-Ni cemented carbides is investigated using open circuit potential monitoring, potentiodynamic polarization, electrochemical impedance spectroscopy, and surface analytical techniques. Results reveal that the corrosion resistance of WC-Co cemented carbide is significantly compromised in the presence of

This study quantifies the influence of impurities on the fracture behavior of tungsten (W) and tantalum (Ta) by examining their effects on ideal cleavage energy and fracture toughness. Using density functional theory (DFT), we calculated the reduction in ideal cleavage energy for both the {100} and {110} crystallographic planes of W and Ta due to various impurities, with He, O, P, and S showing significant

Single-crystal silicon (sc-Si) is a typical infrared material widely used in industries such as semiconductors and infrared imaging. At room temperature, sc-Si exhibits high hardness and brittleness, making it prone to defects like collapse and crack during processing. However, at elevated temperatures, sc-Si can undergo plastic deformation, which is of great significance for improving its manufacturing

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

Practical applications for NbSi alloys encountered difficulties because of their low room temperature fracture toughness and machinability. To achieve rapid alloy formation and enhance its fracture toughness, this study explored the effect of B4C additions on the microstructure and properties of Nb-16Si-20Ti alloy formed by Laser Melting Deposition (LMD). The results showed that the relative densities

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

This paper focuses on La-TZM alloy and introduces a novel method for multi-scale constitutive model parameter identification based on the BP neural network (BPNN) which has not been reported yet, aiming to enhance model prediction accuracy and improve parameter identification efficiency. When the Genetic Algorithm (GA) is used to identify parameters in multi-scale constitutive models with internal

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