Mixture Of Oxides Research Articles

Effect of design parameters of magnetic separator on recovery of metal values from slag waste

Slag generated during the metallurgical processing of iron and steelmaking is principally a mixture of metallic oxide along with silica and other compounds. Although slag is an end waste generated during iron and crude steel production, it comprises a significant amount of metal values. The prime objective of this study is to recover the valuable metals present in the slag waste to minimise the waste generation as well as the adverse impact of disposal on the environment. This study focused on the recovery of magnetic material from steel slag by a magnetic separator based on its mineralogical characteristics and chemical composition. A full factorial experiment was designed for this investigation, and the obtained results were analysed by a mathematical model to validate the effect of process parameters on metal recovery. The optimum conditions were identified, and a confirmation test was also performed at that condition. Recovery of magnetic metal values over 93% was obtained, and the linear regression analysis indicated that the predicted values are in good agreement with the experimental results.

Sensor for operational control of oxygen and combustible gases concentration in waste gases of thermal units

A new sensor has been developed for continuous monitoring of oxygen and combustible gases content in the waste gases of thermal units. The target application of the sensor is its installation in shunt pipes of thermal units, directly into the waste gas flow. The sensor is characterized by one reference gas electrode and three measuring electrodes applied on the surface of a solid electrolyte tube made of a zirconia electrolyte (e.g., 8YSZ). The reference gas electrode and one of the measuring electrodes were made of silver, the second measuring electrode was made of platinum, the third measuring electrode was made of a mixture of zinc oxide (95 wt %) and lanthanum-strontium manganite (5 wt %). The oxygen content in the gas mixture was determined by the well-known potentiometric method in accordance with the Nernst equation, i.e. an Ag|8YSZ|Ag electrochemical cell was used. To determine the products of incomplete combustion of fuel, the method of mixed potential between Pt- and Zn-based electrodes was used; the obtained potential value was determined by the difference in the oxidation rate of carbon monoxide as the main component of unburned fuels, on different materials of measuring electrodes. The experimental results of the sensor for the determination of carbon monoxide, hydrogen, and methane in a gas mixture are presented.

Исследование фазовых превращений в двухслойном жаростойком покрытии Ti–Al–C+Y–Al–O на жаропрочном никелевом сплаве

Currently, an active increase in requirements for fuel efficiency and specific gravity of aircraft turbojet engines is observed. Existing coatings based on zirconium dioxide intended for protecting engine parts are largely outdated and have exhausted their development potential, so new ceramic systems for the production of protective coatings based on them are an area of research. The authors carried out a study of a heat-resistant two-layer coating based on the Y–Al–O system (outer layer) and the Ti2AlC MAX phase of the Ti–Al–C system (sublayer) produced using vacuum-arc deposition on the Inconel 738 heat-resistant nickel alloy and molybdenum by alternate deposition of layers based on Ti–Al–C and a Y–Al–O layer. Using synchrotron radiation, phase transformations in the coating were examined when samples were heated to 1400 °C in a vacuum and to 1100 °C in the atmosphere to study the process of oxidation and coating formation in the presence of oxygen. Using scanning electron microscopy, the authors studied the microstructure and chemical composition of the coating. The study identified that heating the coating in a vacuum and in the atmosphere causes various phase transformations in it, but in both cases, the formation of a mixture of oxides of the Y–Al–O group and destabilization of the Ti–Al–C-based sublayer are observed. After heating the coating in the atmosphere without preliminary heat treatment, the coating was destroyed upon cooling, which was not observed when the coating was heated in a vacuum.

Novel stereoisomeric lignin-derived polycarbonates: towards the creation of bisphenol polycarbonate mimics.

In this work, we have described a family of bio-based polycarbonates (PC-MBC) based on the unique lignin-derived aliphatic diol 4,4'-methylenebiscyclohexanol (MBC) that was sustainably sourced from lignin oxidation mixture. The detailed structure analysis of these polycarbonates has been confirmed by a series of 2D NMR (HSQC and COSY) characterizations. Depending on the stereoisomerism of MBC, the PC-MBC displayed a wide achievable T g range of 117-174 °C and high T d5% of >310 °C by variation of the ratio of the stereoisomers of MBC, offering great substitution perspectives towards a bisphenol-containing polycarbonates. Nonetheless, the most here presented PC-MBC polycarbonates were film-forming and transparent.

Oxide powder mixture with poly-vinyl alcohol (PVA) and added polyethylene glycol (PEG) as plasticizer

Powder mixture consisted of ZnO, Mn2O3 (MnCO3) and Fe2O3 blended powders, was found laminating during compaction. Polyvinyl alcohol (PVA) and a combination of PVA with polyethylene glycol (PEG) added as a plasticizer, were introduced as polymer binders to improve the compaction of oxide mixtures. It has been done by forming a suspension of oxide mixture and varying the polymer solution concentration and composition. By evaporating the solvent, new materials were obtained, which consist of oxide particles bound via polymer. In such a manner obtained hybrid materials were characterized with attenuated total reflection Fourier transformed infrared (ATR-FTIR) spectroscopy, differential thermal analysis (DTA) and transmission electron microscopy (TEM). The oxide polymer material was compacted at 200 MPa and the expansion of this compact during heating was monitored in temperature range up to 550?C with dilatometer. It was found that PVA forms graft polymer with PEG and specific interaction with oxide particles surface was revealed.

In English

The mechanical mixtures of titanium oxide (TiO2) with carbon nanostructures for 3D printing of CJP technology, which are used as consumables for the manufacturing of electrically conductive composite 3D products, are created in this work. Various carbon nanostructures (single- and multi-walled carbon nanotubes and carbon nanofibers) were used in the creation of composite 3D products (TiO2–СNS) by CJP 3D printing technology. Optimal conditions for processing of mechanical mixtures (TiO2/MWCNT) on a planetary ball mixer for composite 3D products (CJP) were studied and proposed. The dose of the deformation influence on the mechanical mixture under optimal conditions of mechanochemical processing (76 J/g), which allows not to deteriorate the electrical conductivity of the material, is determined. The dependence of the electrical conductivity of composite 3D products (CNS/TiO2, where the CNS content is 3 wt. %) on the type of carbon nanostructures (SWCNT, MWCNT and CNF) contained in ceramics (TiO2), is constructed. The exponential dependence of the specific electrical conductivity (G) of composite 3D products (TiO2–MWCNT) on the mass content of multi-walled carbon nanotubes, is also recorded in the work. In the framework of the study of the electrical conductivity of composite 3D products (CJP), a fuel cell cathode based on a Pt/TiO2–MWCNT composite was created. It was found that the catalyst Pt/TiO2–MWCNT, which contains 5 wt. % of carbon nanotubes, has the best catalytic activity in oxygen recovery. At the same time, the average particle size of platinum (Pt) is 5–10 nm, while the content of Pt in the EDX samples is approximately ~10 wt. %. Also, studies were carried out from the mixing of Pt/TiO2-MWCNT composites with MWCNT content 15 and 50 wt. %. Samples were analyzed by transmission and scanning electron microscopy.

Unique Mixture of (MgO-CdO) Nanoparticles as an Adsorbent for Water Treatment

Sol- gel method of synthesis of nanomaterials. Sol gel was applied for synthesis of magnesium oxide (MgO) and cadmium oxide (CdO) nanoparticles. Using magnesium nitrate and cadmium acetate as a raw materials and sodium hydroxide as a solvent for hydrated oxide at room temperature. Hydrated Magnesium oxide and cadmium oxide nanoparticles were annealed in air at 600 °C. The characterization methods include examine the morphology of the oxides surface using field emission scanning electron microscopy (FESEM) and Energy Dispersive X-ray spectroscopy (EDX), Characterization of functional groups was performed using Fourier Transform Infrared analysis (FTIR). X-ray powder diffraction (XRD) was used for examine the size of particles using Debye-Scherrer method. MgO and CdO nanoparticles are produced into spherical structures with average crystallite sizes of (55) and (55.5) nm, respectively. The study of using these nanoparticles as adsorbents were done successfully and the high value of removing percentage of iron about 97.8% and 98.7 respectively. Moreover, the mixture of these nano oxides gives 99.2% releasing of iron ion from polluted water.

Bentonite pillarization using sonication in a solid acid catalyst preparation for the oleic acid esterification reaction

Bentonite is one of the abundant non-metallic minerals and still was not used optimally. Bentonite could be tailored into a high-value material, one of which is a solid catalyst for a particular reaction. In general, the modification of bentonite is by the pillarization process, which is exchanging cations between the alumina-silicate layers of bentonite with a single or mixture of metal oxide, thereby modifying the distance between the layers and its physicochemical properties from the original bentonite. However, the conventional pillarization process is usually time-consuming, especially during on aging process (almost one day). Using sonication during the pillarization process could prepare the pillarization process to become shorter, at least eliminating the aging process. Thus, this study investigated the sonication effect on the pillarization process of bentonite, especially its physicochemical properties. A solid acid catalyst is prepared by the pillarization method with or without the sonication. Zirconium (Zr) and titanium (Ti) are used as the pillared metals. In the bentonite pillarization process using sonication, the amplitude of the ultrasonic probe will be varied at 30, 50, and 70% with a sonication time of 20 min, respectively. The prepared solid acid catalysts are tested for their catalytic activity in the esterification reaction of oleic acid to methyl oleate. Several characterization techniques are also conducted on the prepared solid acid catalysts to obtain information on their physicochemical properties, such as N2 gas adsorption, XRD, NH3-TPD, XRF, and SEM. Conversion of the esterification reaction is verified by calculating the acid value and GC–MS analysis. It is found that the surface area increased after the pillarization process for Ti-PILC and Zr-PILC catalysts, with/without the sonication. The XRD results also confirmed that the basal spacing shifted after the pillarization for both prepared catalysts. It is assumed that the pillarization is prepared successfully by using sonication. Furthermore, the surface area of Zr-PiLC catalysts was significantly enhanced when using sonication, however, not observed for the Ti-PiLC catalyst. The N2 gas adsorption results disclosed that the sonication effects extensively enlarge the pore volume. Similar results are described in the NH3-TPD analysis that the acidity of the prepared catalysts also increased due to the sonication. Therefore, the conversion of the esterification reaction of oleic acid also increased. The maximum value of oleic acid conversion obtained in this study was 62.66% for the solid acid catalyst Ti/PILC, with an amplitude of 70%. It is achieved that using the sonication in the bentonite pillarization process could reduce the pillarization time drastically and cause the prepared material to become more porous.

Применение механоактивации для синтеза Y2Zr2O7 твердофазным способом

The effect of mechanical activation on the synthesis of yttrium zirconate Y2Zr2O7 by solid-phase method was studied. Mechanical activation of a stoichiometric mixture of zirconium and yttrium oxides was carried out in AGO–2 centrifugal planetary mill at a centrifugal factor of 40 g for 10 min. Using X-ray phase analysis and complex thermal analysis, the processes occurring during the calcination of the initial and mechanically activated mixture of oxides were investigated. The calculation of the sizes of Y2Zr2O7 crystallites, carried out according to the Scherrer formula, showed that after annealing the mechanically activated mixture of ZrO2 and Y2O3 in the temperature range of 1100–1200 °C for 3 h, nanocrystalline yttrium zirconate was formed.

Расчёт состава композиции циркон — оксид церия на основе данных рентгеновской дифракции

Based on X-ray diffraction data, a method is described for calculating the composition of a mixture containing cerium-containing solid solutions based on zircon (Zr, Ce) SiO4 and zirconium-containing solid solutions based on cerium oxide (Ce, Zr) O2. The mixture was prepared by calcining at 1200–1600 °С a mechanically activated mixture of zirconium oxide, hydrated amorphous silica and cerium oxide at a molar ratio of ZrO2 : SiO2 : CeO2 equal to 0.95 : 1.00 : 0.05. The content of phases in the composition and the composition of solid solutions were calculated using the Rietveld method and Vegard's rule.

Unusual solid-state transformations in LuFe2O4 films during their synthesis via MOCVD with further reduction

Thin films of lutetium ferrite LuFe2O4, potential components of multiferroic devices, are difficult objects for synthetic solid-state chemistry. In this paper, we report on the successful synthesis of epitaxial LuFe2O4 thin films on YSZ(111) single-crystalline substrates via a two-stage technique. The newly proposed synthesis route combines a novel variant of metal-organic chemical vapor deposition (MOCVD) with subsequent annealing at low oxygen partial pressure provided by the metal/oxide (Fe/FeO) getter. The phase composition and structural transformations during synthesis are studied. It is shown that the orienting effect of the substrate manifests itself in the fine structure of as-deposited films: the LuFe2O4.5 phase forms as a layer (∼5 ​nm thick) adjacent to the substrate. On top of it the layer of hexagonal LuFeO3 (h-LuFeO3) forms. The crystalline layer is then replaced by an amorphous mixture of lutetium and iron oxides. High-temperature annealing at 900 ​°C and partial oxygen pressure (pO2) laying in the region of thermodynamic stability of LuFe2O4 leads to the formation of films that are well-crystallized over the entire thickness of the sample. At the same time, it was discovered that a thin epitaxial layer (∼5 ​nm) of Lu2O3 forms at the interface with the substrate. The proposed scenario of the appearance of this layer implies the partial evaporation of the iron oxide (FeO) from the film surface during annealing, which is accompanied by diffusion of iron and oxygen ions from the interface to the upper surface of the film. It was also established that the solid-state reaction between h-LuFeO3 and FeO is an essential stage in the formation of LuFe2O4. Transmission electron microscopy (TEM) images of the model samples reveal that wustite penetrates the interlayer space between lutetium and iron-containing layers, which leads to the formation of well-ordered (FeO)2(LuO2)1 structure.

Facile and scalable preparation of ultralight cobalt@graphene aerogel microspheres with strong and wide bandwidth microwave absorption

Cobalt@graphene aerogel microspheres (GCoAMs) with tunable porous structures are fabricated by using a unique spraying and crosslinking coagulation method. The graphene oxide (GO) and sodium alginate (SA) mixture aqueous dispersions were used for spraying. The cross-linking reaction occurs quickly between the carboxylic group of SA in the sprayed microdroplets and metal Co2+ in the collector bath, which fixes the microsphere shape and in-situ immobilizes the metal ion. After freeze-drying and the subsequent high-temperature thermal reduction, the ultralight GCoAMs are obtained. The pore structures of GCoAMs can be controlled by varying the GO/SA ratio. The GCoAMs exhibit strong and wide broadband microwave absorption due to its hierarchical porous structures and graphene/metal Co hybrid composition. At a GCoAMs loading content of 1.5 wt%, the minimal reflection loss reaches as high as −70.4 dB with a thin specimen thickness of 2.2 mm at 13.18 GHz and its effective absorption band achieves 5.65 GHz with a specimen thickness of 1.98 mm. At 2 wt% GCoAMs, the effective absorption band achieves 6.09 GHz with a specimen thickness of 2 mm, covering the whole Ku band. This work provides a novel, low-cost and easily scale-up method for preparing the lightweight and efficient microwave absorbers, which could be used in microwave telecommunication fields.

Interaction of Components of Epoxy Composite Containing Carbon Nanotubes and Graphene Oxide Mixture

Mixtures of carbon nanotubes (CNTs) and graphene oxide (GO) in composite materials often exhibit synergistic effects with respect to mechanical and electrophysical properties. In this paper, the mechanisms of interaction between CNTs, GO and epoxydian resin macromolecules were discussed based on the results of molecular dynamics simulations. Calculations were performed in the MM3 force field at exposure times up to 100 ps. The influence of the CNT’s graphene layers shape and the presence of oxygen-containing functional groups on the self-assembly process during the epoxy composite formation has been demonstrated. It is shown that graphene oxide sheets are arranged around cylindrical nanotubes and envelop them, while when using tapered nanotubes, the formation of alternating layers of CNTs and GO should be expected. The presence of oxygen-containing groups on the surface of cylindrical nanotubes promotes the penetration of epoxydian resin macromolecules into the space between CNTs and GO. The simulation results of the "cylindrical CNTs - GO" and the "conical CNTs - GO" hybrid particles were confirmed by scanning electron microscopy data.

The effect of plasma-assisted ball milling on preparation and sintering behavior of (Zr0.1429Hf0.1429Ce0.1429Y0.2857La0.2857)O2-δ high entropy fluorite oxide

The sintering process of high entropy fluorite oxide ceramics prepared by the conventional solid-phase reaction method suffers from high single-phase synthesis temperature, low densities, and abnormal grain growth. To improve the sintering characteristics of high entropy fluorite oxide ceramics, the oxide mixture was dealt with dielectric barrier discharge plasma-assisted ball milling. The samples were analyzed using XRD, SEM, TEM, TG/DTG, visual high-temperature deformation analyzer, and nanoindentation meter. The results show that the plasma field activates the raw material powder and promotes powder finer. The rapid heating effect of the plasma during the ball milling process causes micro-area sintering and micro-area melting on the powder surface, which increases the active sites of the solid phase reaction of the material, accelerates the mass transfer process, and improves the sintering activity. Compared with conventional ball milling, plasma-assisted ball milling reduces the single-phase synthesis temperature of high entropy ceramics from 1500 °C to 1300 °C. The sintered ceramic pellets have intact grain growth, no noticeable abnormal grain growth, and improved density and mechanical properties.

Dynamics of Pressure Variation in Closed Vessel Explosions of Diluted Fuel/Oxidant Mixtures

Nitrous oxide is widely used as oxidizer or nitriding agent in numerous industrial activities such as production of adipic acid and caprolactam and even for production of some semiconductors. Further, it is used as an additive in order to increase the power output of engines, and as an oxidizer in propulsion systems of rockets, because it has a large heat of formation (+81.6 kJ mol−1). N2O is highly exothermic, and during its decomposition a supplementary heat amount is released, so it needs special handling conditions. The combustion of fuels in nitrous oxide atmosphere can lead to high unstable and turbulent deflagrations that speedily self-accelerate and therefore a deflagration can change to a detonation. The peak explosion pressure and the maximum rate of pressure rise of explosions in confined spaces are key safety parameters to evaluate the hazard of processes running in closed vessels and for design of enclosures able to withstand explosions or of their vents used as relief devices. The present study reports some major explosion parameters such as the maximum (peak) explosion pressures pmax, explosion times θmax, maximum rates of pressure rise (dp/dt)max and severity factors KG for ethylene-nitrous oxide mixtures (lean and stoichiometric) diluted with various amounts of N2, at various initial pressures (p0 = 0.50–1.50 bar), in experiments performed in a spherical vessel centrally ignited by inductive-capacitive electric sparks. The influence of the initial pressure and composition on pmax, θmax and (dp/dt)max is discussed. The data are compared with similar values referring to ethylene-air mixtures measured in the same initial conditions. It was found that at identical C/O ratios with ethylene-air, ethylene-N2O-N2 mixtures develop higher explosion pressures and higher rates of pressure rise, due to the exothermic dissociation of N2O under flame conditions.

Computational model development for heat production of Al-CaO flameless ration heaters (FRHs): The effect of temperature, pressure, and pH on the exothermic characteristics

The principle of the Al-CaO flameless ration heaters (FRHs), as a kind of portable chemical energy device for self-heating food packaging, is to release a large amount of heat mainly through the complex chemical reactions of the mixture of aluminium powder, calcium oxide, and water for reheating food. The effect of temperature (20–130 °C), pressure (101.325–607.95 kPa), and pH (12.70–13.40) on the heat production of the thermogenic agent were investigated. A computational model for FRHs' actual heat production was established based on the internal stratification phenomenon and then verified with five ratios of Al to CaO (45:55, 50:50, 55:45, 60:40, 65:35). Results showed that temperatures greater than 120 °C would promote the increase in solids content and decrease in liquid water of the reaction products. It mainly caused the insufficient reaction response of the thermogenic agent in the inner layer of the heater. The increasing pH could vastly increase the reaction rate and shorten the response time. The pressure has no apparent effect on the chemical reaction of the mixture. The computation method proposed in this study enables stable and precise calculation of the actual heat production by Al-CaO FRHs. The results of this study provide a deep understanding and insight into Al-CaO FRHs and are helpful for designing and optimizing food self-heating units.

Refinery Wastewater Treatment by a Novel Three-Dimensional Electrocoagulation System Design

A novel three-dimensional electrocoagulation method was used in the current work to explore the treatment of refinery wastewater. Metal-Impregnated Granular Activated Carbon (MIGAC) was employed as a third particle electrode in the inventive design. A comprehensive investigation has been conducted to evaluate its performance. BET-specific surface area, total pore volume, X-ray Fluorescence (XRF), Energy-Dispersive X-ray spectroscopy (EDS), and Scanning Electron Microscopy (SEM) were employed for the characterization of MIGAC particle electrodes at pH=7, 30V applied voltage, 10g of particle electrodes, 175mL/min flow rate, and a supporting electrolyte (0.063M NaCl + 0.025M Na2SO4). The findings indicate that the effectiveness of Chemical Oxygen Demand (COD) elimination increased quickly after 20min to 66.93, 69.88, 77.59, 74.14, 81.26, 79.87, and 87.14% for Conventional Electrocoagulation (CEC). Three-dimensional electrocoagulation with granular activated carbon (TEC-RGAC), TEC-MIGAC (Al), TEC-MIGAC (Fe), and TEC-MIGAC (Al:Fe) with molar ratios of (1:1), (1:2), and (2:1) respectively were utilized. While turbidity removals were 99.04, 98.87, 99.23, 94.89, 92.42, 98.85, and 99.21% for CEC ,TEC-RGAC, TEC-MIGAC(Al), TEC-MIGAC(Fe), TEC-MIGAC(1:1), TEC-MIGAC(1:2), and TEC-MIGAC(2:1) respectively. The results demonstrated that the metal impregnation of GAC is an interesting method for achieving effective turbidity and COD removal from refinery wastewater. In both batch and repeat recycling tests, MIGAC with a mixture of aluminum and iron oxides removed turbidity and COD more effectively and efficiently than RGAC.

Parametric and economic analysis of high-temperature cascade organic Rankine cycle with a biphenyl and diphenyl oxide mixture

High-temperature organic Rankine cycle (ORC) systems have the potential to improve the heat-to-power conversion efficiency and expand the temperature range for heat recovery, heat battery and solar power generation. Restricted by the critical temperature of the commonly used organic working fluids, the current ORC technology has a maximum working temperature of around 300 °C. This paper proposes a high-temperature cascade organic Rankine cycle (CORC) system using a biphenyl and diphenyl oxide (BDO) mixture as the top cycle fluid and conventional organic fluids for the bottom cycle. The BDO mixture has excellent heat stability over a wide operation condition from 12 °C to 400 °C in single-phase and binary-phase states. However, at present a detailed study on the ORC using the mixture is lacking. In this paper, a parametric analysis of the high-temperature CORC system is conducted. A mathematical model based on the equivalent hot side temperature is built to simulate the ORC efficiency. The thermodynamic and exergetic performances of the novel CORC system under different bottom ORC working fluids, mixing chamber temperatures, evaporation temperatures, and condensation temperatures are investigated. The results show the maximum thermal efficiency of the CORC system is 38.74 % and 40.26 % at top ORC evaporation temperatures of 360 °C and 400 °C. The largest exergy destruction takes place in the heat exchanger between the top and bottom ORCs. Besides, the heat regenerators have a significant impact on the thermodynamic performance and can elevate the CORC efficiency by about 4 %. The proposed system has a higher efficiency and a lower equipment cost than conventional steam Rankine cycle at 400 °C while eliminating the challenges of wet steam turbines.

PREVENTION OF PREVIOUS OPERATION OF CHARGES OF PYROTECHNICAL PRODUCTS BASED ON MIXTURES OF MAGNESIUM, ALUMINUM POWDER AND METAL WASTE IN THE CONDITIONS OF EXTERNAL THERMAL ACTIONS

Mathematical models of external heating of charges of pyrotechnic products based on compacted mixtures of aluminum-magnesium alloy powders and nitrate-containing oxidizers (sodium, potassium, strontium, and barium nitrates) were refined by taking into account the temperature dependence of their thermophysical properties (volumetric heat capacity and coefficient of thermal conductivity), which allowed to more accurately determine the critical values of heat flows and durations of their influence.
 New data were obtained to determine the critical ranges of the change in the burning rate of mixtures under conditions of elevated heating temperatures and external pressures for various values of technological parameters (the coefficient of excess oxidizer α; the average particle size of metal fuel powders dм microns and oxidizer dN), exceeding the ranges of which leads to premature ignition mixtures under conditions of external thermal effects and leads to unstable explosive development of their combustion process and fire-hazardous destruction of pyrotechnic products.

Influence of oxide polluted lubricants on friction: Trapping mechanisms

In wire winding processes, the thermal pretreatments required in the wire manufacturing process pollute the wire with a lubricant and oxide mixture. This mixture disturbs the tribological conditions at the wire/tool interface during shaping and the final quality of the product to be obtained. During shaping, the lubricant and oxide mixture accumulates and creates a wear groove in the wire guide. The observation of these grooves indicates that the erosion is caused by the presence of third-body particles which initially crack the groove with a widening of the crack thereafter. The wire/tool contact is then reproduced under conditions close to industrial conditions on a pin-on-disc test. The influence of oxide pollution and lubricant quality on the conditions is measured and demonstrated.