In this study, focused radio wave (RW) assisted leaching was investigated for the first time to considerably enhance the efficiency of copper leaching from its low-grade ores. For this purpose, the effect of exposure to radio wave electromagnetic irradiation was experimentally investigated. Two series of leaching tests were conducted, in the form of agitated slurry and fixed-bed column modes. The experimental

Agglomeration provides substantial advantages on heap leaching, such as creating a porous heap to improve low-permeability ore leaching efficiency, as well as building an environmentally friendly heap by reducing metal releases from waste rock and tailings. In this study, we employed synchrotron X-ray computed tomography (X-ray CT) combined with a data-constrained modelling (DCM) approach to investigate

The widespread use of selective catalytic reduction (SCR) catalysts will provide many waste SCR catalysts. These spent catalysts can be identified as hazardous solid waste because they contain a lot of heavy metals. This work aims to develop a clean, green, and economical way to recover valuable metals and regenerate the catalyst. The effect parameters of hydrogen peroxide and ammonium carbonate concentration

Ball mill plays a key role in mineral processing plant, and its load identification for optimal control has great significance for the energy consumption reduction and production efficiency improvement. The vibration signal of ball mill shell contains abundant load information, which can be used to identify ball mill load. However, due to the non-linear and non-stationary characteristics of vibration

Though extensive studies have been performed on high entropy alloys, there is still a lack of understanding of their high-temperature deformation mechanisms. By systematically analyzing the high-temperature behavior of fine-grained and coarse-grained CoCrFeMnNi and Al0.5CoCrFeMnNi high-entropy alloys (HEAs) studied in this work and reported in the literature, their constitutive deformation equations

The temperature effect on deformation behavior, microstructural evolution and fracture mechanism of Inconel 625 superalloy sheet were systematically investigated in a wide temperature range from room temperature (RT) to 950 °C. Tensile temperature was varied in increments of 50 °C after reaching 500 °C. Obvious serrations occurred at the medium temperature range and evolved in the sequence of B→B+C→C

Cu2ZnSnS4 (CZTS) thin films were deposited successfully with four different compositions, namely, Cu-rich, Sn-rich, Zn-rich and near-stoichiometric CZTS, by a dual thermal evaporation technique to investigate the effect of stoichiometry on the physical properties of the deposited films. The thin films were characterized by energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction, Raman spectroscopy

Based on the large extraction efficiency of 10 – 200 μg cm-2 h-1, the electrolysis-based technology is one of the most promising methods for large-scale extraction of lithium resources from natural seawater. The high potential safety hazard is the inherent defect of the conventional two-electrode electrolytic cell because of the threshold voltage of 3.9 V, which is very close to the decomposition voltage

The design of cobalt-free cathode substance with unexceptionable electrochemical property and high thermochemical stability is an important target for IT-SOFC. In this work, the impact of some rare earth elements doping on the construction, TEC, DC conductivity and electrochemical properties of Nd1.9Ln0.1CuO4 (Ln=La, Nd, Sm and Ce) are investigated. Nd1.9Ln0.1CuO4 forms single tetragonal structure

Interface engineering of LiMn2O4 (LMO) is a promising strategy to enhance the lithium storage capability and cycling stability of cathode materials in Li-ion batteries (LIBs). This is because the strategy prevents structural degradation; however, Li storage kinetics remains unsatisfactory, resulting in poor ultrafast cycling performance. Therefore, we fabricated an Nb-doped TiO2 (NTO) functional layer

Features of the local structure of ZrO2-Yb2O3, ZrO2-Y2O3-Yb2O3 and ZrO2-Sc2O3-Yb2O3 single crystals have been studied using optical spectroscopy. The probability of oxygen vacancies to occupy the first coordination shells of the Sc3+, Yb3+ and Y3+ stabilizing oxide cations has been shown to vary in the test solid solutions. Furthermore it has been shown that the probability of oxygen vacancies to occupy

316L stainless steel samples were manufactured by selective laser melting (SLM). The microstructure of SLM-made 316L stainless steel and the room temperature tensile properties both perpendicular and along the building direction were studied and characterized. The static temperature field during the molten pool formation was simulated by finite element simulation. It indicates that the nonlinear asymmetrical

ABSTRACT Part I of this investigation, addressing two-phase systems, showed that etherdiamine produces more stable and dryer foams, whereas smaller bubbles are formed with faster kinetics by ethermonoamine. These remarkable differences in foam stability, attributed to the distinct chain length and consequent hydrophilic–lipophilic balance, influence froth properties, and may affect the selectivity

The effects of ultrafine WC content on the microstructure, mechanical properties and wear resistance of regenerated coarse grained WC-10Co cemented carbides have been investigated by SEM, mechanical property tests and wear test. The results show that with the increase of ultrafine WC content, the average grain size of the regenerated cemented carbides increases first and then decreases. When the ultrafine

Ultrafine WC-10Co cemented carbides with different Cr2(C,N) inhibitor contents and different-scaled WC powders were prepared by low-pressure sintering. Their influence on the microstructure and mechanical performances were investigated and expounded in this work. The result shows that the Cr2(C,N) addition homogenized the microstructure of the cemented carbides and refined WC grains. With the Cr2(C

ABSTRACT The morphology of eutectic carbide was studied by application of a transverse static magnetic field (TSMF) during the directional solidification of M2 high-speed steel. The results show that the morphology of eutectic carbide changed from lamella to fibre as the magnetic flux density (MFD) increased from 0 to 1 T. The transformation from lamella to fibre has been enhanced by the increasing

ABSTRACT The optimal hot metal desulphurisation (HMD) slag is defined as a slag with a sufficient sulphur removal capacity and a low apparent viscosity (ηslag) which leads to low iron losses. In part I of this study, the fundamentals behind the optimal slag were discussed. In this part these fundamentals are explored by a Monte Carlo simulation, based on FactSage calculations, plant data analysis and

ABSTRACT It is of great significance to improve the yield of ferroalloy for steelmaking to reduce cost and save energy. In this paper a kind of loss mechanism of micro-carbon ferromanganese which has micro content of carbon during RH refining of interstitial free steel was investigated. The flow field of argon gas in the RH degassing vessel was investigated through numerical simulation. Through force

ABSTRACT Top gas recycling technology is an effective means to reduce fuel consumption and CO2 emission in the ironmaking field. In this work, a static mathematical model of COREX process combined with top gas recycling technology is developed based on material and energy balance. The influence of three types of top gas recycling, such as the recycle gas without CO2 removal (RG-1), the recycle gas

ABSTRACT In the present study, the influence of industrial sinter machine speed on the temperature distribution of the bed is evaluated using a one-dimensional transient mathematical model. The model is developed considering the law of conservation of mass, momentum, and energy of solid and gas phases. The prediction of bed temperature from the model is compared with the measured lab scale pot test

ABSTRACT The dynamic blockage behaviour of fine particles in a packed bed was simulated using the discrete element method (DEM). The influence of key variables are examined. The calculation results showed that fine particles blockage in packed bed are easy to occur in the area where fine particles just enter the bed. The mechanism of blockage formation is mainly due to mechanical interactions between

ABSTRACT In this research, the effects of laser surface hardening treatment on the phase transformation of austempered and quench-tempered grey cast irons were investigated. It was found that there were four zones in the matrix of austempered grey cast iron and three zones in the matrix of quench-tempered grey cast iron produced by the laser hardening process. Both cast irons had central laser-hardened

In this paper, the influence of the Fe2O3 addition amount on the dephosphorization of hot metal at 1623 K with the slag of the low basicity (CaO/SiO2) of about 1.5 was investigated by using high-temperature laboratorial experiments. With increasing the Fe2O3 addition amount from 5 to 30 g, the contents of [C], [Si], [Mn] and [P] in the hot metal at the end of dephosphorization are decreased and the

The particle shape influences the part properties in laser powder bed fusion, and powder flowability and powder layer density (PLD) are considered the link between the powder and part properties. Therefore, this study investigates the relationship between these properties and their influence on final part density for six 1.4404 (316L) powders and eight AlSi10Mg powders. The results show a correlation

Industries demand stringent requirements towards economical machining without hindering the surface quality while cutting high carbon high chromium (HcHcr) steel. Electrical discharge machining (EDM) of HcHcr steel aims at reducing machining cost (i.e., maximize material removal rate (MRR) and minimize tool wear rate (TWR)) with good surface quality (i.e., minimize surface roughness (SR)). A comparative

In this article, a novel Co3O4@TiO2 composite is synthesized by applying two-step methods. ZIF-67 is synthesized and used as a template for the synthesis of the composite. The composite is designed by using the effective photocatalytic properties of Co3O4 and TiO2. The resulting synthesized composite is supposed to offer superior properties compared to their counterparts. The synthesized Co3O4@TiO2

An innovative way to utilize deep-sea manganese nodules is described in this paper. The manganese nodules were reduced by aluminothermy and subsequently added into aluminum as a mixture of alloying elements in their natural ratio. The microstructure and properties of aluminum alloys containing 1.2, 7.7, and 9.7 wt % of reduced nodules were studied. The alloys were formed by Al matrix and minor amounts

The possibility of applying a combined concentration and metallurgical method for processing low-grade and refractory copper–nickel ores was considered. The resulting rougher and scavenger flotation concentrate contained 2.07% nickel and 0.881% copper at a recovery of 85.44% and 89.91%, respectively. The concentrate was then roasted with ammonium sulfate, followed by aqueous leaching of clinker to

It is well-documented experimentally that the influence of hydrogen on the mechanical properties of structural alloys like austenitic stainless steels, nickel superalloys, and carbon steels strongly depends on temperature. A typical curve plotting any hydrogen-affected mechanical property as a function of temperature gives a temperature THE,max, where the degradation of this mechanical property reaches

In steel foundries, ceramic filters are often used to capture non-metallic inclusions. It is well documented that solid inclusions are captured and retained within the filter macropores at the metal-refractory interface. However, liquid inclusions appear to be captured and retained by two mechanisms: one within the filter web micropore structure and another as a liquid film at the metal-filter macropore

Silicon sulfide (SiS2) was synthesized from Si, SiC, Si3N4, and a eutectic Al-Si liquid. An Ar-CS2 gas mixture, after bubbling through liquid CS2, was passed over pulverized Si, SiC, Si3N4, or a eutectic Al-Si alloy liquid. White, needle-shaped SiS2 was precipitated as a single phase on the colder downstream surface when Si powder in a SiO2 liner was heated over 1273 K. This deposition mechanism involves

Pressurized electroslag remelting (PESR) has been widely used for preparation of high-quality high nitrogen steels. However, desulfurization might be limited by the pressurized-nitrogen atmosphere in the process. In this paper, the desulfurization behaviors of electroslag remelting in air and nitrogen pressure were investigated and further an appropriate method to improve the sulfur removal in PESR

Kinetics of face-centered cubic (FCC) phase evolution in equiatomic AlCoCrFeNi alloy has been studied in this work, measuring the phase fraction from X-ray diffraction (XRD). As-cast alloy showed a body-centered cubic (BCC)+B2 structure. Heat treatments performed at different temperatures showed the formation up-to 30 to 35 pct FCC phase between 1073 K and 1373 K. A systematic decrease in hardness

The secondary explosive welding process promotes the diffusion of the carbon element and accumulation of chromium carbide, which leads to a decrease of tensile properties and toughness of the material. In this work, the average shear strength value increased from 400 to 421 MPa. The crack of the fatigue specimens started from the inclusions rich in alumina near the surface, and the harmful hard-phase

The effect of nitrogen additions on fatigue behavior has been examined in near-equiaxed, rolled Ti-6Al-4V bar. This is the first-time nitrogen content that has been systematically explored with respect to monotonic and cyclic properties in a Ti-6Al-4V alloy base composition. Nitrogen additions were found to increase the \(\beta \)-transus temperature and strength, but they decreased ductility, even

Selective laser melting (SLM) is an additive manufacturing (AM) technique designed to use a high energy density laser to fuse metallic powders for producing three-dimensional parts. So far, most studies of SLM have been focused on using virgin metal powders. There are few comprehensive studies on the microstructure and mechanical properties of SLM-produced parts using recycled powders, especially for

In this work, a novel polycrystalline Mn5Ge2.9Fe0.1 compound has been prepared and a detailed analysis on structural, physical and magnetocaloric properties is carried out. Mn5Ge2.9Fe0.1 compound is a second order-itinerant ferromagnet with enhanced Sommerfeld coefficient. The resistivity of this compound is found to show saturation at high temperatures due to spin fluctuations in the compound. Critical

The elongation of high-strength copper alloy with tensile strength over 1300 MPa is generally less than 3%. In this paper, a novel Cu–20Ni–20Mn-0.3Nb-0.3Cr-0.1Zr(wt.%) alloy was prepared, of which the tensile strength, elastic modulus and elongation is 1445 MPa, 147 GPa and 6.8%, respectively. The flow stress strain and microstructure evolution during high temperature deformation at different strain

Oxidation behavior of a Ti2AlNb based alloy (Ti–22Al–23Nb (at.%)) and hot corrosion behavior of this alloy coated with a salt mixture of NaCl–Na2SO4 at 1023 K were comparatively investigated. The results showed that the alloy possessed relatively good oxidation resistance while suffered severe hot corrosion attack. The mass gain of the hot-corroded alloy was much larger than that of the oxidized alloy

Polymeric nanoparticles dispersed in an aqueous medium were synthesized using the miniemulsion technique. In this study, nanoparticles composed of copolymer F8T2, homopolymer MDMO-PPV and a mixture of both were investigated aiming to unravel the interaction between these materials. By decreasing the distance between the nanostructured materials, higher Förster resonance energy transfer (FRET) was observed

N-type β-Indium sulfide (β-In2S3) has emerged as one of the most promising semiconductor photoanode for use in photoelectrochemical water-splitting in recent years, its defective spinel structure facilitates the incorporation of foreign ions to adjust the photoelectrochemical (PEC) performance. Lanthanide ions with excellent optical properties and abundant energy level structure have attracted much

We investigate the anisotropy in thermoelectric transport properties of pristine and self-doped InTe after spark plasma sintering and ascribe the observed weak anisotropy to the lack in orientation preference of investigated specimens as characterized by the scanning electron microscope. Then, the effect of Cu/Na doping on the transport properties of InTe is discussed for comparison, which suggests

Mercury ion (Hg2+) can affect the quality of water and cause damage to human health. Therefore, the detection of Hg2+ in water, especially trace Hg2+, is very important. However, the detection limit (approximately 200 pM) of conventional Hg2+ sensors is far lower than the detection limit (7.5 pM) proposed by the US Environmental Protection Agency for measuring Hg2+. Here, we have developed a novel

Here, we report a facile strategy to synthesize MgCo2O4 with abundant oxygen vacancies (OV-MgCo2O4) using for the electrode materials of asymmetric supercapacitors (ACS). Benefiting from the NaBH4 reduction treatment to offer oxygen vacancies, the specific capacitance of OV-MgCo2O4 was improved to 460 F g−1 (1 A g−1), much higher than untreated MgCo2O4 (340 F g−1 at 1 A g−1). We fabricated OV-MgCo2O4//AC

Most recent studies for improving tensile properties of wire arc additive manufactured Ti–6Al–4V focused on layer-by-layer plastic deformation but with complicated operation. Previous study demonstrated that a sub-transus solution increased the strength and decrease the anisotropic ductility by generating a new micro-lamellae recrystallization to discontinue α grain boundaries (αGB). The current study