A high content silicon aluminum alloy (Al-25Si-4Cu-1Mg) coating was prepared on a 2A12 aluminum alloy by supersonic plasma spraying. The morphology and microstructure of the coating were observed and analyzed. The hardness, elastic modulus, and bonding strength of the coating were measured. The wear resistance of the coating and 2A12 aluminum alloy was studied by friction and wear test. The results

The present paper reports the effective utilization of marble sludge powder (MSP) for the recovery of potash values from waste mica scrap using chlorination roasting-water leaching method. Characterization studies indicated the presence of dolomite as the major mineral phase in MSP, whereas muscovite and quartz were observed in the mica sample. The acid leaching studies suggest a maximum of 22% potash

Graphene has excellent theoretical properties and a wide range of applications in metal-based composites. However, because of defects on the graphene surface, the actual performance of the material is far below theoretical expectations. In addition, graphene containing defects could easily react with a matrix alloy, such as Al, to generate brittle and hydrolyzed phases that could further reduce the

A Monte Carlo Potts model was developed to simulate the recrystallization process of a cold-rolled ultra-thin grain-oriented silicon steel. The orientation and image quality data from electron backscatter diffraction measurements were used as input information for simulation. Three types of nucleation mechanisms, namely, random nucleation, high-stored-energy site nucleation (HSEN), and high-angle boundary

The influence of nitrogen content on the precipitation of secondary phases and the tensile strength of Alloy 718 during gas tungsten arc welding was investigated. Various types of precipitates were characterized using scanning electron microscopy and transmission electron microscopy. The results showed that in the fusion zone, the volume fraction of Nb-rich phases such as Laves, (Nb,Ti)C, and δ phases

A 0.3wt% graphene nanoplatelets (GNPs) reinforced 7075 aluminum alloy matrix (7075 Al) composite was fabricated by spark plasma sintering and its strength and wear resistance were investigated. The microstructures of the internal structure, the friction surface, and the wear debris were characterized by scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. Compared with the original

The hardness, wettability, and electrochemical properties of Ti6Al4V alloy surfaces treated with anodic oxidation and plasma oxidation as well as the viabilities of the different cell lines on the obtained surfaces were investigated. The anodic oxidation was performed for 10 min under 100 V potential, and it resulted in a 0.95 µm thick nanoporous anatase-TiO2 structure. On the other hand, plasma oxidation

This study investigated the interdiffusion of calcium ferrite/calcium titanate system in the time range of 0–120 min by the diffusion couple method in a CO/N2 reducing atmosphere at 700°C. The results show that after the diffusion reaction occurred, no longitudinal agglomerations were present on the substrate surface on the calcium titanate side. When the diffusion time was increased to 105 min, a

The surface treatment is important for titanium and its alloys as promising candidates for dental implantation due to their bioinert surface. Titanium surface samples were modified using H2O2 solution at different times up to 72 h to boost their bioactivity. According to the results of the field emission scanning electron microscopy test, some nanostructures are formed on the surface of treated titanium

To quickly predict the fatigue limit of 6061 aluminum alloy, two assessment methods based on the temperature evolution and the steady ratcheting strain difference under cyclic loading, respectively, were proposed. The temperature evolutions during static and cyclic loadings were both measured by infrared thermography. Fatigue tests show that the temperature evolution was closely related to the cyclic

Voids (referred to as “stopes”) are generally created during underground mining activities and can lead to both local and regional geotechnical instabilities. To assist in managing the stability of mining-related voids and improving the recovery of orebodies, tailing-based backfill technology has been widely used around the world. In the design of tailing-based backfill strategy, the specific function

Flash processing (FP) has attracted considerable attention due to its high efficiency, economic advantages, and the extraordinary opportunity if offers to improve the mechanical properties of steel. In this study, we investigated the influences of FP on the recrystallization (REX) behavior and mechanical performance of cold-rolled IF steel. Using a thermomechanical simulator, we performed both single-stage

High-density tailings, small cementitious materials, and additives are used for backfill materials with poor early compressive strength (ECS), which may greatly affect the mining and backfill cycle, to prepare paste backfill materials (PBMs) with a high ECS. The effects and mechanisms of different early strength agents on the property of PBM are investigated. The action mechanism of additives on the

To improve the oxidation properties of ferritic heat-resistant steels, an Al-bearing 9Cr-5Si-3Al ferritic heat-resistant steel was designed. We then conducted cyclic oxidation tests to investigate the high-temperature oxidation behavior of 9Cr-5Si and 9Cr-5Si-3Al ferritic heat-resistant steels at 900 and 1000°C. The characteristics of the oxide layer were analyzed by X-ray diffraction, scanning electron

The preparation of functional material titanium carbide by the carbothermal reduction of Ti-bearing blast furnace slag with microwave heating is an effective method for valuable metals recovery; it can alleviate the environmental pressure caused by slag stocking. The dynamic dielectric parameters of Ti-bearing blast furnace slag/pulverized coal mixture under high-temperature heating are measured by

This study aimed to investigate the microstructure and mechanical properties of TixZrVNb (x = 1, 1.5, 2) refractory high-entropy alloys at room and elevated temperatures. The TiZrVNb alloy consisted of the body-centered cubic (BCC) matrix with a small amount of V2Zr phase. The Ti1.5ZrVNb and Ti2ZrVNb alloys exhibited a single-phase BCC structure. At room temperature, the tensile ductility of the as-cast

Refractory high-entropy alloys (RHEAs) are emerging as new materials for high temperature structural applications because of their stable mechanical and thermal properties at temperatures higher than 2273 K. In this study, the mechanical properties of MoNbTaTiW RHEA are examined by applying calculations based on first-principles density functional theory (DFT) and using a large unit cell with 100 randomized

The evolution of the microstructure and tensile properties of dual-phase Al0.6CoCrFeNi high-entropy alloys (HEAs) subjected to cold rolling was investigated. The homogenized Al0.6CoCrFeNi alloys consisted of face-centered-cubic and body-centered-cubic phases, presenting similar mechanical behavior as the as-cast state. The yield and tensile strengths of the alloys could be dramatically enhanced to

Inconel 718 is a Ni-Fe-based superalloy widely used in aerospace engines because of its excellent mechanical properties. However, the inferior stability of the γ″ phase limits the application of Inconel 718, which coarsens rapidly at temperatures greater than 650°C. Further improving the temperature tolerance of Inconel 718 requires optimization of the phase configuration via modification of the alloy’s

The mining industry produces billions of tons of mine tailings annually. However, because of their lack of economic value, most of the tailings are discarded near the mining sites, typically under water. The primary environmental concerns of mine tailings are related to their heavy metal and sulfidic mineral content. Oxidation of sulfidic minerals can produce acid mine drainage that leaches heavy metals

The effect of microstructure and passive film on the corrosion resistance of 2507 super duplex stainless steel (SDSS) in simulated marine environment was investigated by electrochemical measurements, periodic wet-dry cyclic corrosion test, scanning Kelvin probe force microscopy, atomic force microscopy, and X-ray photoelectron spectrometry. The results show that the occupation ratio of γ phase increases

In underground mining, there has been an increasing use of “cemented paste” for the backfilling of stopes. As this cemented paste backfill (CPB) enters the stope as a fluid, shotcrete barricades are often used to retain the fill material during and after the filling operations. However, failures of barricades have been reported around the world in recent years. This paper presents an analytical solution

To investigate the interaction mechanism between 95Cr saw-wire steel and different refractories, we conducted laboratory experiments at 1873 K. Five crucible materials (SiO2, Al2O3, MgO·Al2O3, MgO, and MgO-CaO) were used. The results indicate that SiO2, Al2O3, and MgO·Al2O3 are not suitable for smelting low-oxygen, low-[Al]s 95Cr saw-wire steel, mainly because they react with the elements in the molten

A process of biooxidation followed by thiosulfate leaching of gold from refractory gold concentrate was investigated. Mineralogical studies on the concentrate showed that very fine gold grains (<10 µm) were encapsulated in pyrite and arsenopyrite, while the proportion of monomer gold was only 21%. The gold-bearing sample was identified as a high-sulfur fine-sized wrapped-type refractory gold concentrate

Small-particle interlayers (lenticles) show some characteristic hydraulic properties and can affect the movement of unsaturated water. In this study, we developed a novel online capillary-water-absorption monitoring device and conducted three groups of comparison tests to simulate lenticle positions and thicknesses with respect to the capillary rise. The results show that the characteristic wetting

Two dissimilar steel plates, structural steel and mild steel, were joined by explosion welding to form a composite. The composite was then heat-treated by quenching at 840°C for 30 min followed by tempering at 200°C for 3 h. The microstructure was investigated under an optical microscope and a scanning electron microscope. The mechanical properties were measured using Vickers microhardness and Charpy

The composition of tailings particles in mines plays a key role in the flocculation settlement of slurries. To study the influence of coarse particle tailings (CPTs) on the flocculation settlement of tailings slurries (TSs), static flocculent settling tests, scanning electron microscopy observations, and laser particle size analyses were conducted using the tailings obtained from a copper mine. The

Recycling and reusing materials from waste have become a nexus in the development of sustainable materials, leading to more balanced technologies. In this study, we developed a composite coating by co-depositing recycled ceramic particles, pulverised fly ash (PFA) and medical ceramics (MC), into a nickel-phosphorus matrix using a typical electroless plating process. Scanning electron microscopy (SEM)

Friction stir processing (FSP) can be used to improve surface composites. In this study, a modified method of FSP called friction stir vibration processing (FSVP) was applied to develop a surface composite on AZ91 magnesium alloy. In this technique, the workpiece is vibrated normal to the processing direction. The results illustrated that compared with the FSP method, the FSVP caused a better homogeneous

Rutile titania (TiO2) was successfully prepared via hydrolysis of TiCl4 in the presence of AlCl3. The powders were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. In the present system, AlCl3 functions as a nucleating agent and induces the formation of rutile TiO2. The influences of HCl and isopropanol concentrations

Mine closure is associated with many negative impacts on society and the environment. If these effects are not rationally addressed, they would pose risks of mine closure. Thus, a risk management method is needed to mitigate these adverse impacts and address mine-closure issues. An integral framework for mine-closure risk management that includes risk assessment and risk treatment was proposed. Given

Friction stir processing of an Al0.1CoCrFeNi high entropy alloy (HEA) was performed at controlled cooling conditions (ambient and liquid submerged). Microstructural and mechanical characterization of the processed and as-cast HEAs was evaluated using electron backscatter diffraction, micro-hardness testing and nanoindentation. HEA under the submerged cooling condition showed elongated grains (10 µm)

Compared with solid metals, liquid metals are considered more promising cathodes for molten slat/oxide electrolysis due to their fascinating advantages, which include strong depolarization effect, strong alloying effect, excellent selective separation, and low operating temperature. In this review, we briefly introduce the properties of the liquid metal cathodes and their selection rules, and then

The quasi-metallic fibers were selected from 1 to 40 pieces and connected in parallel in this study. The giant magneto impedance (GMI) effect of Co-based melt extract fibers in the bundle mode was investigated, and the distribution of the surface circumferential magnetic field on the fibers was also analyzed. Such distribution was induced by the driving current, which gave rise to the circular magnetization

A new variant of friction-assisted process named friction surface alloying (FSA) for developing surface alloys was demonstrated in the present work. In FSA, the dispersed phase is melted and allowed to react with the matrix material to form an alloy at the surface of a metallic substrate. In the present work, magnesium (Mg) sheets and zinc (Zn) powder were selected, and fine grained (∼3.5 µm) Mg-Zn

Coal and gas outburst is a frequent dynamic disaster during underground coal mining activities. After about 150 years of exploration, the mechanisms of outbursts remain unclear to date. Studies on outburst mechanisms worldwide focused on the physicochemical and mechanical properties of outburst-prone coal, laboratory-scale outburst experiments and numerical modeling, mine-site investigations, and doctrines

Pure metal-doped (Cu,Zn)Fe2O4 was synthesized from Zn-containing electric arc furnace dust (EAFD) by solid-state reaction using copper salt as additive. The effects of pretreated EAFD-to-Cu2(OH)2CO3·6H2O mass ratio, calcination time, and calcination temperature on the structure and catalytic ability were systematically studied. Under the optimum conditions, the decolorization efficiency and total organic

Ultrasonic vibration assisted tungsten inert gas welding was applied to joining stainless steel 316L and low alloy high strength steel L415. The effect of ultrasonic vibration on the microstructure and mechanical properties of a dissimilar metal welded joint of 316L and L415 was systematically investigated. The microstructures of both heat affected zones of L415 and weld metal were substantially refined

The potential autoclave was used to study the catalytic mechanism of Cu2+ during the oxygen pressure leaching process of artificial sphalerite. By studying the potential change of the system at different temperatures and the SEM-EDS difference of the leaching residues, it was found that in the temperature range of 363–423 K, the internal Cu2+ formed a CuS deposit on the surface of sphalerite, which

Ore particles, especially fine interlayers, commonly segregate in heap stacking, leading to undesirable flow paths and changeable flow velocity fields of packed beds. Computed tomography (CT), COMSOL Multiphysics, and MATLAB were utilized to quantify pore structures and visualize flow behavior inside packed beds with segregated fine interlayers. The formation of fine interlayers was accompanied with

Surface charges and hydration are predominant properties of colloidal particles that govern colloidal stability in aqueous suspensions. These properties usually coexist and interact with each other. The correlation between the surface charge and hydration of minerals is summarized on the basis of innovative experimental, theoretical, and molecular dynamics simulation studies. The factors affecting

We report the picosecond laser ablation of aluminum targets immersed in a polar organic liquid (chloroform, CHCl3) with ∼2 ps laser pulses at an input energy of ∼350 µJ. The synthesized aluminum nanoparticles exhibited a surface plasmon resonance peak at ∼340 nm. Scanning electron microscopy images of Al nanoparticles demonstrated the spherical morphology with an average size of (27 ± 3.6) nm. The

A high-building multi-directional pipe joint (HBMDPJ) was fabricated by wire and arc additive manufacturing using high-strength low-alloy (HSLA) steel. The microstructure characteristics and transformation were observed and analyzed. The results show that the forming part includes four regions. The solidification zone solidifies as typical columnar crystals from a molten pool. The complete austenitizing

This work introduces the facile hydrothermal synthesis of double perovskite La2CuCoO6. X-ray diffraction pattern confirmed the formation of a monoclinic phase with P121/c1 symmetry. Transmission electron microscopy results revealed that the self-assembled porous rods were composed of nanocrystallite aggregates. The estimated specific surface area of these mesoporous rods with an average pore diameter

Graphene/aluminum (Gr/Al) composites have attracted the attention of researchers all over the world due to their excellent properties. However, graphene agglomerates easily because of the van der Waals force between graphite sheets, thereby affecting the performance of the composites. Decreasing the agglomeration of graphene and dispersing it uniformly in the Al matrix is a key challenge. In the preparation

Duplex stainless steels (DSSs) used in subsea structures and desalination industries require high corrosion and erosion resistance as well as excellent mechanical properties. The newly introduced cast duplex grade ASTM A890 7A has a unique composition and is expected to have a much better resistance to corrosion and erosion compared with the super-duplex grades 5A and 6A. This work is a comparative

For the purpose of exploring a potential process to produce FeMn, the effects of microwave heating on the carbothermal reduction characteristics of oxidized Mn ore was investigated. The microwave heating curve of the mixture of oxidized Mn ore and coke was analyzed in association with the characterization of dielectric properties. The comparative experiments were conducted on the carbothermal reductions

This study investigated the hot corrosion performance of a dissimilar weldment of Ni-based superalloy and stainless steel joined by CO2-laser welding and improved by high-velocity oxy-fuel (HVOF) coating in a Na2SO4-60wt%V2O5 environment at 900°C. A dissimilar butt joint of AISI 321 and alloy 825 was fabricated by CO2-laser welding with low heat input after obtaining the optimum welding parameters

Pore structure is an important factor influencing coke strength, while the property of coke is essential to maintaining gas and liquid permeability in a blast furnace. Therefore, an in-depth understanding of the pore structure evolution during the graphitization process can reveal the coke size degradation behavior during its descent in a blast furnace. Coke graphitization was simulated at different

The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate (VTC) by adding CaCO3 was investigated. Thermodynamic analysis was employed to show the feasibility of calcium titanate formation by the reaction of ilmenite and CaCO3 in a reductive atmosphere, where ilmenite is more easily reduced by CO or carbon in the presence of CaCO3. The effects of CaCO3 dosage

Despite the existence of conventional methods for recycling chips, solid-state techniques have become popular, whereby waste metals are directly recycled into consolidated products with the desired shapes and designs. We investigated the feasibility of recycling phosphor bronze chips through a hot extrusion process using aluminum powder as a metal binder for the fabrication of a metal-fiber-reinforced

A novel method for exfoliating graphite oxide (GrO) was implemented through the mass water absorption of a GrO—poly(ethylene glycol) (GrO—PEG) composite. The GrO—PEG composite was prepared by intercalating PEG into the lamellae of GrO, and the variation of the basal spacing was measured by X-ray diffraction analysis. The yield of graphene was measured with an ultraviolet—visible spectrophotometer,

The evolution of oxide inclusions during isothermal heating of 18Cr-8Ni stainless steel with yttrium addition at temperatures of 1273 to 1573 K was investigated systematically. Homogeneous spherical Al-Y-Si(-Mn-Cr) oxide inclusions were observed in as-cast steel. After heating, most of the homogeneous inclusions were transformed into heterogeneous inclusions with Y-rich and Al-rich parts, even though

(GO/TiO2)N (GO represents graphene oxide, and N represents the period number of alternate superposition of two dielectrics) one-dimensional photonic crystal with different lattice constants was prepared via the sol-gel technique, and its transmission characteristics for photocatalysis were tested. The results show that the lattice constant, filling ratio, number of periodic layers, and incident angle

Cold metal transfer plus pulse (C + P) arc was applied in the additive manufacturing of 4043 Al alloy parts. Parameters in the manufacturing of the parts were investigated. The properties and microstructure of the parts were also characterized. Experimental results showed that welding at a speed of 8 mm/s and a wire feeding speed of 4.0 m/min was suitable to manufacture thin-walled parts, and the reciprocating

A simple and novel technique for the preparation of anatase TiO2 nanopowders using natural ilmenite (FeTiO3) as the starting material is reported. Digesting ilmenite with concentrated H3PO4 under refluxing conditions yields a white α-titanium bismonohydrogen orthophosphate monohydrate (TOP), Ti(HPO4)2·H2O, which can be easily isolated via gravity separation from unreacted ilmenite. The addition of

The main aim of this study was to investigate liquation cracking in the heat-affected zone (HAZ) of the IN939 superalloy upon tungsten inert gas welding. A solid solution and age-hardenable filler metals were further studied. On the pre-weld heat-treated samples, upon solving the secondary γ′ particles in the matrix, primary γ′ particles in the base metal grew to “ogdoadically diced cubes” of about

Hydrogen metallurgy is a technology that applies hydrogen instead of carbon as a reduction agent to reduce CO2 emission, and the use of hydrogen is beneficial to promoting the sustainable development of the steel industry. Hydrogen metallurgy has numerous applications, such as H2 reduction ironmaking in Japan, ULCORED and hydrogen-based steelmaking in Europe; hydrogen flash ironmaking technology in

To produce a highly refined microstructure, several metals or alloys have been processed via equal-channel angular pressing (ECAP). In this work, the mechanical and microstructural changes of the 5083 aluminum alloy in H11 condition after processed by two ECAP passes were investigated. An ECAP H13 steel die with an inner angle (α) of 120° and outer curvature (β) of 20° was used. The microstructural

To better understand the stress-corrosion behavior of friction stir welding (FSW), the effects of the microstructure on the stress-corrosion behavior of the FSW in a 2198-T34 aluminum alloy were investigated. The experimental results show that the low-angle grain boundary (LABs) of the stir zone (SZ) of FSW is significantly less than that of heated affected zone (HAZ), thermo-mechanically affected