Addition Of Tin Research Articles

Development of DLC-Coated Solid SiAlON/TiN Ceramic End Mills for Nickel Alloy Machining: Problems and Prospects

The study is devoted to the development and testing of technological principles for the manufacture of solid end mills from ceramics based on a powder composition of α-SiAlON, β-SiAlON, and TiN additives, including spark plasma sintering powder composition, diamond sharpening of sintered ceramic blanks for shaping the cutting part of mills and deposition of anti-friction Si-containing diamond-like carbon (DLC) coatings in the final stage. A rational relationship between the components of the powder composition at spark plasma sintering was established. The influence of optimum temperature, which is the most critical sintering parameter, on ceramic samples’ basic physical and mechanical properties was investigated. DLC coatings’ role in changing the surface properties of ceramics based on SiAlON, such as microrelief, friction coefficient, et cetera, was studied. A comparative analysis of the efficiency of two tool options, such as developed samples of experimental mills made of SiAlON/TiN and commercial samples ceramic mills based on SiAlON, doped with stabilizing additives containing Yb when processing nickel alloys (NiCr20TiAl alloy was used as an example). DLC coatings’ contribution to the quantitative indicators of the durability of ceramic mills and the surface quality of machined products made of nickel alloy is shown.

Bronze votive pins from the sanctuary of Athena Alea at Tegea, Arcadia, Greece, ca. 9th-7th BCE: A microscopic and compositional study using portable micro X-ray fluorescence spectrometry (micro-XRF)

We examined an assemblage of 72 copper alloy pins from the Athena Alea sanctuary at Tegea in central Peloponnese, Greece, dated to the 9th-7th centuries BCE, with a stereo-microscope and with micro X-ray fluorescence spectrometry. The microscopic and elemental analyses investigated the technology and metalworking practices used in the sanctuary’s votives with a micro-invasive analytical protocol. Results confirmed that the assemblage consists of copper-tin binary alloys and provide evidence for the continuity of bronze in the Tegea area during the Geometric (9th-7th century BCE) and Orientalising (7th century BCE) periods. Most of the artefacts are made of bronze with an average tin content of ca. 9 wt% Sn, while a small group (n= 3) of pins is tin-free (<0.3 wt% Sn). Tin concentrations in the alloys do not correlate with the typology of the pins. The results further suggest an intentional addition of tin, as indicated by the normal distribution of tin values, along with a local metallurgical technology, that catered for the local sanctuary’s demand for votive objects.

Microstructure and optical properties of sputter-deposited Ga2O3 films

We report on the properties of gallium oxide (Ga2O3) thin films deposited on c-plane sapphire substrates using radio frequency magnetron sputtering under various conditions. The parameters varied included the composition of the deposition gas, the substrate temperature, and postdeposition annealing temperature. The optical characteristics obtained by UV-VIS spectroscopy showed excellent transparency of 90%–95% for all the films obtained. The structural and compositional properties of the films were determined using x-ray diffraction and energy dispersive spectrometry measurements. The films deposited in Ar at 400 °C showed diffraction peaks at 18.6°, 37.2°, and 58.2°, which are attributed to diffraction peaks from (2¯01), (4¯02), and (6¯03) planes of β-Ga2O3. Postdeposition annealing in N2 at 400–900 °C did not make any improvement in the crystalline quality of the films. The addition of tin in the films produced transparent films whose optical bandgaps decreased with increasing tin concentration in the films.

Effects of Structural and Textural Aspects on the Photocatalytic Performance of Zirconium Hydrogen Phosphate Doped with Tin Metal

The preparation of zirconium hydrogen phosphate, α-Zr(HPO4)2 · H2O (α-ZrP), and its tin dopped derivatives were described. The structural and textural properties of the prepared materials were examined and their effect on catalytic performance in the removal of dyes such as methyl red and methylene blue from the aqueous solutions was revealed. The crystalline zirconium hydrogen phosphate was prepared by the interaction between zirconium tetrachloride and phosphoric acid in the presence of fluoric acid. The α-ZrP samples doped with tin were obtained by the impregnation method. X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy and nitrogen adsorption analysis were applied to explore the structural and textural properties of α-ZrP modified by the addition of various amounts of tin. The obtained results indicated a significant effect of the tin amount on these properties. As a result of tin addition, a gradual decrease in the crystallinity of the samples was observed with the appearance of preferred orientation for the [002] planes. These changes coincided with an increase in the surface area and the total pore volume as well as a decrease in pore diameter. Investigation of the photocatalytic activity of the studied materials in the degradation methyl red and methylene blue indicated a significant increase in the degradation extent of the dyes with increasing amount of tin.

Effect of tin addition on corrosion resistance and microstructure of Cu-based shape memory alloy

Abstract This research investigates the effect of tin addition on corrosion resistance and micro structure of Cu-Al-Ni shape memory alloy with addition three different percentages of Tin (0.3, 1 &3)wt% to the base alloy. These alloys were prepared by casting and pouring in the metallic mold under argon atmosphere, then the prepared ingots were homogenized and machined by wire cutting into a small samples for corrosion test. X-ray diffraction inspection and scanning electron microscope were used for microstructural observations. Corrosion tests were carried out in sea water (3.5 wt% NaCl solution) at three different temperatures (25, 40 and 60) °C. The results showed that the corrosion resistance increased with addition percentage of tin metal and with rising temperature, It was observed that the 3% tin addition gave the best results in corrosion rate with rising temperature upto 60 °C and also in microstructure the same percentage gave a fine grain size Then the 0.3% Tin Addition and Finally the 1% Tin Addition.

Mechanism of action of tin on the semi-conductive properties of PbO layer in lead acid battery

Although antimony in alloys for lead-acid batteries has better mechanical and electrochemical performance, it reduces the excessive potential for hydrogen evolution, resulting in excessive water loss and self-discharge of the battery. This paper aims to examine the action of tin in PbSn using different techniques. In this work, the addition of tin in PbCa was intended to suppress the premature capacity loss (PCL) caused by the substitution of antimony in the PbSb alloy by calcium that has good mechanical properties and a high hydrogen evolution potential (200 mV higher than that of antimony). This substitution induces the formation of a passive film composed mainly of α-PbO. The mechanism of action of tin on the anodic film obtained at 700 mV vs. Hg/Hg2SO4/K2SO4 saturated electrode with Pb – (0–5) wt.% Sn in 0.5 mol/L sulfuric acid solution at 25 °C was studied using electrochemical impedance spectroscopy (EIS), AC voltammetry, Mott–Schottky plots and X-ray diffraction (XRD) of the film obtained. It was found that tin stops the growth of the anodic film due to the co-precipitation of certain conductive oxides which reduce the thickness of the passive film and increase its conductivity. A mechanism of action of tin on the electrochemical behavior of the anodic film was suggested based on the results.

When Cermet Applied for Hard Machining of Steel: A Review

Providing an information deals with the application of Ceramic Metal (Cermet) as a cutting tool applied for hard machining of steel is the objective of this review paper. Cermet is made of hard metals and was introduced just after the invention of Cemented Carbide. As a cutting tool, the conventional Cermet was known as TiC-based Cermet. Unfortunately, it was not as successful as Cemented Carbide due to its brittleness of low fracture toughness of TiC substrate. Thanks to TiN material. The addition of TiN improved the fracture toughness, and the modern era of Cermet was begun. A TiCN-based modern Cermet is characterized microstructurally by a structured hard phase featuring core-rim structure embedded in a tough Co-Ni binder. The effort to refine the fracture toughness of TiCN Cermet is discussed in this paper including the effort to raise its performance through coating technologies. In particular, its performance which is given in term of productivity and represented by volume of removal rate (VMR) is discussed. Finally, conclusions and recommendation for future works are written.

TECHNOLOGY FOR THE MANUFACTURE OF CATHODES INTENDED FOR SPRAYING BACTERICIDAL COATINGS ON GLASS SURFACES

The paper presents the course and results of research into the production of cathodes for sputtering bactericidal coatings on glass surfaces in an industrial magnetron line at D.A. Glass. The study included the development of an innovative and comprehensive technology for producing various types of cathodes using a vacuum induction furnace. FactSage software was used for numerical simulations of phase transformations in the liquid and solid phase during the cooling and solidification of alloys, and the liquidus and solidus temperatures were determined using the thermal analysis method (DTA). The cathodes were made by casting plates that are components of ready-made cathodes. Zonal macrosegregation tests were carried out in the plate casting, which showed that the cast plates were characterised by high homogeneity in the entire volume. The chemical compositions of the cathodes corresponded to the required compositions, and their quality met the requirements for installation in a magnetron, which proves the correctness of the developed technologies of their production. The layers on the glass, sputtered in a magnetron device, were subjected to microbiological tests to determine the bactericidal (biocidal) properties of the glass. Preliminary results of these studies showed that the cathodes based on brass and bronze of the following type exhibited the best bactericidal properties: Cu90Sn10, Cu90Zn10, Cu80Zn10Al10, Cu80Ti20 and Cu65Ni18Zn17. The layers produced on the glass with the use of these cathodes exhibited the ability to deactivate the tested strains of microorganisms, including the elimination of bacterial growth. To further improve these properties, the composition of copper-based cathodes with various additions of tin and titanium, and with the addition of the following rare earth elements: cerium and lanthanum, which will be subjected to layer sputtering in the magnetron and microbiological tests as part of the next stages of the project, was modified.

Sintering Behavior and Fracture Morphology of NiFe2O4/Nano-TiN Ceramics Synthesized under Argon Atmosphere

NiFe2O4/nano-TiN ceramics were synthesized by a two-step cold-pressing sintering process. Sintering behavior, fracture morphology, mechanical performance and high-temperature conductivity were investigated. The results indicated that besides NiO and NiFe2O4, new Ni3TiO5 and metallic phases (iron and nickel) formed in the sintered samples. TiN accelerated the grain growth along with considerable quantity of micro-pores in the sintered samples. Compared to the un-doped samples, the temperature for the onset of sintering of the NiO-Fe2O3-2.0 wt.% TiN system decreased from 1093 to 985 °C. TiN addition changed the sintering mechanism of the NiO-Fe2O3 from grain boundary diffusion to volume diffusion. TiN additions reduce the apparent sintering activation energy and porosities and improve the density, bending strength, and pyroconductivity. Three-dimensional fracture morphology of the composite ceramics synthesized under argon atmosphere, exhibits self-similarity characteristics and the fractal dimension for NiFe2O4-1.0 wt.% TiN ceramics is 2.0813.

In Ukrainian

Methanol carbonylation (MC) to produce acetic acid is a strategically important large-scale process (Monsanto and BP Chemicals Cativa TM ), which is carried out under high pressure in the liquid phase using Rh(Ir) catalysts and extremely toxic halide cocatalysts/promoters. In addition to acetic acid, methyl acetate is also an industrially important product of MC. The halogen-free heterogeneous-catalytic process of methanol carbonylation in the vapor phase using catalysts containing no noble metal, in particular Ni-based on carbon supports, provides a number of advantages over homogeneous systems, including the possibility of multifold use of catalytic compositions. Important factors that cause the formation of acetyls are the textural, acidic properties of the catalysts, the presence of modifying/promoting additives in their composition. Nickel and copper chlorides supported on activated carbon were shown in [Catal. Today. 2004. 93–95:451] to catalyze the vapor-phase MC process producing methyl acetate at ambient pressure in the absence of alkyl halides in the gas reaction mixture. This paper presents the results of the studying the effect of supports (activated carbon of BAU-A (AC), SKT, SUGS grades; structured – cordierite, Al 2 O 3 /cordierite) of copper-nickel chloride catalysts, characterized by the low-temperature ad/desorption, XRD, TPD-NH 3 , TPR-H 2 techniques; modifying additives of tin on the production of methyl acetate in the halide-free vapor-phase methanol carbonylation under ambient pressure. It is shown that the yield 18 % of the target product in the presence of a catalyst on activated carbon of the BAU-A grade significantly exceeds the Y MeOAc 3 and 7 % indices for NiCl 2 -CuCl 2 compositions on SKT and SUGS, respectively. The formation of methyl acetate on NiCl 2 -CuCl 2 /AC is facilitated by the optimal combination of the porous structure characteristics (the presence of mesopores with an average diameter of ~ 7 nm) and the surface acidity of the specified catalyst, which are favorable for the activation of reagent molecules of the MC process. Methyl acetate yield of 15 % in the presence of NiCl 2 -CuCl 2 compositions on ceramic honeycomb supports (synthetic cordierite) with a specific surface area ~ 0.5 m 2 /g, commensurate at 355–360 °C with Y MeOAc for NiCl 2 -CuCl 2 /AC, is achieved due to more efficient mass transfer and heat removal in the exothermic reaction of methanol carbonylation compared to highly porous catalysts. The conclusion is substantiated that the modification of the NiCl 2 /AC sample with tin additives provides an increase in the yield of the target product from 2 to 11 %, which may be caused by the formation of intermetallic phase crystallites Ni 3 Sn within NiCl 2 -Sn/AC (identified by XRD) under conditions of catalysis – adsorption/activation sites of CO molecules.

Hot pressing and microstructural characterization of SiC and TiN added TiB2 ceramics

This investigation aimed to study the individual and synergic impacts of SiC and TiN additives on the sinterability and microstructure of TiB2-based ceramics. The hot-pressing method at 2000 °C was implemented to fabricate the samples. All three samples reached their near full densities thanks to the beneficial role of the incorporated phases. In terms of the TiB2–SiC composite, the in-situ SiO2 was produced over the sintering process because of a chemical reaction between TiO2 oxide and SiC reinforcement. On the other hand, the X-ray diffraction (XRD) pattern, along with the microstructural observations, revealed the in-situ formation of hexagonal BN (hBN) in the TiB2–TiN system. Moreover, the dissolution of boron into the TiN additive led to the formation of a solid solution, and consequently, a strong diffusion bonding was achieved. Although no hBN compound was identified in the ternary system of TiB2–SiC–TiN, the results confirmed the generation of TiC and TiC0·3N0.7 ingredients during the hot pressing.

Erosion wear behavior of spark plasma-sintered Ti-6Al-4V reinforced with TiN nanoparticles

The extensive application of titanium alloys is delimited as their erosion wear properties deteriorate when exposed to erosive and harsh environments. The present research investigates the effects of TiN additions (2, 4, and 6 vol.%) on the Ti-6Al-4V alloy prepared by spark plasma sintering technique. Erosion wear behaviour of the composites was investigated by high-velocity solid particle erosion test and tribometer pin-on-disc friction module method. The duration of the test was 10 min, while the mass loss of the sample was recorded after 2-min interval. The surface analysis and phase identifications of the sintered composites were examined by optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD), respectively. Microstructural analysis revealed a transformation from lamellar with β grain boundaries in Ti-6Al-4V alloy to bimodal structures upon addition of TiN nanoparticles. XRD patterns of the alloy indicated an increase in diffraction peaks from lower intensity to high intensity with an increase in TiN nanoparticle content. Erosion is visible in Ti-6Al-4V alloy, 4 and 6 vol.% TiN, but less severe with 2 vol.% TiN addition for all the test times. However, this is due to grain detachment of the hard phase regions between the matrix and the reinforcing phase of the composites. The results showed the presence of micro-voids on the eroded surfaces. It was found that Ti-6Al-4V alloy with TiN nanoparticle addition was resistant to erosion wear, while the recorded steady-state friction coefficients for all the samples range from 0.2 to 0.4. However, an increase in microhardness values ranges from 342 to 513 HV0.1.

Effect of TiO2 and TiN on the Viscosity, Fluidity, and Crystallization of Fluorine‐Free Mold Fluxes for Casting Ti‐Bearing Steels

TiN inclusions are known to exacerbate slag rimming and nozzle clogging during continuous casting of Ti‐bearing steels. Herein, the effect of TiO2 and TiN on the viscosity and fluidity of a fluorine‐free (F‐free) mold flux, as well as the corresponding precipitated crystalline phase is studied. Higher TiO2 is found to lower the viscosity and increase the strip length of the molten slag at TiO2 contents less than 10 wt%, whereas the viscosity increases suddenly and the strip length decreases rapidly at TiO2 contents above 10 wt%, due to the precipitation of CaTiO3 crystals, resulting in a solid–liquid coexisting melt. TiN has a low solubility in F‐free mold fluxes without MnO additions, and TiN is distributed in the molten slag as solid particles. TiN addition significantly increases the viscosity and shortens the strip length of the molten slag. On the other hand, F‐free mold fluxes containing MnO dissolves TiN into the molten slag through the oxidization of TiN to TiO2. However, beyond the solubility limit of TiN in fluorine‐free mold fluxes containing 5 wt% MnO, excess TiN is not completely dissolved. Then, the precipitation of Ca2Ti2O6 crystals is promoted.

Conversion of methane and n-pentane over Pt-Sn/γ-Al2O3 systems under non-oxidative conditions

Monometallic catalysts Pt/Al2O3 and Sn/Al2O3 and bimetallic systems Pt—Sn/Al2O3 with the platinum and tin contents ∼0.51 and 0.13–0.38 wt.%, respectively, were synthesized. The introduction of tin into the Pt/Al2O3 catalyst decreases the electron deficiency and dispersion of platinum but exerts almost no effect on the concentration of the Lewis acid sites on the support surface. The degree of dehydrogenation of the activated forms of methane (CHx fragments) on the catalysts with tin additives is lower than that on the surface of the monometallic Pt/Al2O3 catalyst. The reactivity of the CHx species formed on the surface of the Pt—Sn/Al2O3 samples was studied in the co-conversion of the activated forms of CH4 with n-pentane to benzene and toluene under the non-oxidative conditions. The introduction of tin into the Pt/Al2O3 decreases the electron deficiency of platinum but does not decrease the yield of aromatic hydrocarbons. The modifying effect of tin appears as a decrease in the degree of dehydrogenation of the activated forms of methane, which results in an increase in the reactivity of activated methane during co-conversion with n-pentane.

Impact of Bi and Sn on Microstructure and Corrosion Resistance of Zinc Coatings Obtained in Zn-AlNi Bath

The paper presents results of studies on the impact of bismuth and tin additions to the Zn-AlNi bath on microstructure and corrosion resistance of hot dip galvanizig coatings. The structure at high magnifications on the top surface and cross-section of coatings received in the Zn-AlNiBiSn bath was revealed and the microanalysis EDS (energy dispersion spectroscopy) of chemical composition was determined. The corrosion resistance of the coatings was tested relatively in a neutral salt spray test (NSS), and tests in a humid atmosphere containing SO2. Electrochemical parameters of coatings corrosion were determined. It was found that Zn-AlNiBiSn coatings show lower corrosion resistance in comparison with the coatings received in the Zn-AlNi bath without Sn and Bi alloying additions. Structural research has shown the existence of precipitations of Sn-Bi alloy in the coating. It was found that Sn-Bi precipitations have more electropositive potential in relation to zinc, which promotes the formation of additional corrosion cells.

Effect of Tin Addition on Shape Memory Effect and Mechanical Properties of Cu-Al-Ni Shape Memory Alloy

This study examines the effect of Sn additions on Cu-14%Al-4.5%Ni shape memory alloy. Sn was added in three different percentages (0.3,1,3) %. The alloys were mechanically tested both in compression test and micro hardness test. Also, a thermo-mechanical test was performed on the alloys. Results showed an increase in the transformation temperature outside the domain and also a better recovery strain with the increase of Sn percentage of 3% Sn addition showed the best results in mechanical properties while the 3% Sn showed a better Shape Memory Properties near to super elastic.

Susceptor-assisted fast microwave sintering of TiN reinforced SiAlON composites in a single mode cavity

In the present study, 17 wt % TiN reinforced α-β SiAlON composites were sintered at low temperature by susceptor-assisted microwave heating. The effect of TiN addition on dielectrical properties of starting powders, as well as the influence of sintering temperature on phase evolution, microstructure development and mechanical properties of α/β-SiAlON-TiN composites were investigated. The obtained results showed that TiN addition increased the microwave absorbing properties which is reflected in the peak sintering temperature. Thus, the α:β ratio decreased and mechanical properties were improved, especially the fracture toughness of the composites. Furthermore, an estimate of energy consumption during microwave assisted sintering at the laboratory scale is presented. As a result, the highest values for relative density (97.1%), Vickers hardness (13.35 ± 0.47 GPa), and fracture toughness (7.52 ± 0.54 MPa m1/2) were obtained by microwave sintering for 30 min at 1300 °C.

All-electrochemically synthesized tin and nickel oxide-modified hematite as photo-electrocatalyst anodes for solar-driven water splitting

Sn- and NiOx-modified Fe2O3 (hematite) films were entirely synthesized via electrodeposition procedure, followed by thermal treatment, and tested as photo-electrocatalyst for water splitting, in alkaline electrolyte. The optimization of the Sn and NiOx electrodeposition loadings on Fe2O3 produced a maximum photocurrent density of 1.35 mA cm−2 at 1.23 V (vs. RHE), with the highest shift on the reaction onset potential, representing a large improvement in relation to bare hematite. Long-term photoelectrolysis studies of the Fe2O3/Sn-10/NiOx at 1.23 V showed that the photocurrent density remained stable for at least 24 h. The assessment of the results from the calculations of charge separation (ƞsep) and charge injection (ƞcat) efficiencies revealed an improvement in both parameters, with the addition of tin into hematite. This was ascribed to its beneficial effect on lowering the charge recombination of the photogenerated charge carriers on grain-boundaries and on the hematite/electrolyte interface. Additionally, it was evidenced that NiOx was more important on the increase in the charge injection, since it is a hole collector, acting as co-catalyst, which improves charge transfer rate at the interface with the electrolyte. The outcome of the Mott-Schottky analysis displayed a negative shift of the flat band potentials (Efb) for both, Sn- and NiOx-modified photo-electrocatalysts, due to the passivation of the surface states, and this was in agreement with the mathematical fitting of the curves obtained via photoelectrochemical impedance spectroscopy (PEIS) measurements. The present findings clearly showed that, by allowing a fine-tuning of the amount of the metal modifiers and with an efficient deposition at functional sites of the hematite, this electrodeposition method is a promising strategy to boost hematite performance as photo-electrocatalyst.

Effect of indium and tin additives on the surface morphology of zinc negative electrodes for Zn-Ni flow-assisted batteries

The effects of In and Sn additives on the charging behavior of Zn negative electrodes for Zn-Ni flow-assisted batteries were investigated. The addition of InCl 3 ･4H 2 O or K 2 SnO 3 ･3H 2 O to the electrolyte suppressed the formation of mossy shaped Zn, which was highly filamentous electrodeposit and a typical cause of a battery failure. In was effective even at concentrations as low as 1.0 mmol dm −3 , while more than 25 mmol dm −3 was required for the case of Sn. The results of ICP-AES measurements indicated that the difference was explained by higher reduced amount of In than that of Sn during the charging process. The In additive did not show any negative effects on the Coulombic and voltaic efficiencies, which was in accordance with the polarization behavior of Zn in the In containing solution; electrodeposited In had high overpotential for hydrogen evolution and minor influences on the Zn deposition potential. From SEM observation at the early stages of electrodeposition, the compact Zn deposits were formed by mitigating the localized deposition on layer-like Zn structures. As a mechanism behind such a uniform deposition by In, a compositional analysis in depth showed deposited In was accumulated at the surface of the deposits. • Effects of In addition on reactions of Zn negative electrode were investigated. • In exhibited a better performance in forming the compact Zn deposits than Sn. • This was caused by the higher content of In in the deposits than the content of Sn. • The compact Zn deposits were formed by the concentrated In at the surface.

Microstructure–property correlation in nano-diamond and TiN added TiC-based ceramics

In this paper, the effect of TiN and nano-diamond additives on the microstructure and properties of TiC-based composites, produced by spark plasma sintering method, was investigated. The thermal conductivity of TiC ceramic was improved significantly due to the incorporation of nano-diamond additive. Although the introduction of diamond worsened the sintering behavior of the sintered TiC ceramic, it enhanced the formation of continuous network of the graphitized diamond at the grain boundaries. However, the addition of TiN to the TiC-diamond sample led to the formation of nitrogen gas at high temperatures, resulting in a semi-porous ceramic containing ~13% porosity. Furthermore, the unreacted TiN was dissolved in the matrix, creating a solid solution of Ti(C,N). Despite the beneficial influence of nano-diamond on the thermal conductivity of TiC, the incorporation of TiN and nano-diamond in TiC ceramics decreased the flexural strength and hardness.