Forthcoming articles

 


International Journal of Microstructure and Materials Properties

 

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International Journal of Microstructure and Materials Properties (23 papers in press)

 

Regular Issues

 

  • The impact of zirconia nano-rods on the methanol permeability and conductivity of Nafion   Order a copy of this article
    by Rudzani Sigwadi, Simon Dhlamini, Touhami Mokrani, Patrick Nonjola, Fulufhelo NEMAVHOLA 
    Abstract: The aim of this paper is to observe the effect of zirconia nanofiller in methanol crossover, mechanical strength and conductivity of modified Nafion
    Keywords: zirconia nanoparticles; nanocomposite membranes; water contact angle; permeability; conductivity; modulus of elastic.

  • Identification of corrosion mechanisms on 13% Cr martensitic stainless steel in thiosulphate containing chloride solution by acoustic emission technique   Order a copy of this article
    by Luigi Calabrese, Edoardo Proverbio, Massimiliano Galeano 
    Abstract: The use of brine containing thiosulphate solution to simulate the sour gas environment was recently evaluated in the scientific literature to overcome the problems related to H2S use for laboratory testing of CRA for Oil & Gas industry. However, corrosion attacks on stainless steel alloys are strongly influenced by thiosulphate to chloride concentration ratio. The identification of a reliable non destructive monitoring technique that can allow to distinguish between the different corrosion mechanisms is a big issue and it is the main aim of the present paper. Corrosion behavior under tensile load of 13% Cr martensitic stainless steel in a modified NACE TM0177 standard solution at room temperature in presence of thiosulphate ions at different concentration (from 10-3 to 10-1 M) was evaluated by Acoustic Emission technique. By microstructural observations and a bivariate analysis it was possible to evidence how some acoustic emission patterns can clearly identify specific corrosion mechanisms.
    Keywords: thiosulphate; pitting; stress corrosion cracking; acoustic emission;.

  • Tuning the porous texture of carbon materials derived from chlorination of Ti(C5H5)2Cl2 for potential electrochemical capacitors   Order a copy of this article
    by Daniel Araujo Perez, Pedro Gonzalez García, Martha Poisot Vazquez, Leandro Garcia Gonzalez 
    Abstract: Variation of the reaction time at 30, 60, 90 and120 min on the chlorination of Ti(C5H5)Cl2, at 900
    Keywords: Carbon materials; Surface features; Capacitances; Cyclic voltammetry; Electrochemical impedance.

  • Effect of process parameters on the hardness and wear resistance performance of laser cladded Ti-Si coatings on Ti-6Al-4V alloy   Order a copy of this article
    by ZWOTHE MASWUMA, ABIMBOLA PATRICIA POPOOLA 
    Abstract: Laser cladding of silicon powder on Ti-6Al-4V titanium alloy was carried out using an ND:YAG laser. Ti-6Al-4V possesses poor tribological properties along with a hardness value that is on the low side. Therefore, the aim of this study is to improve its wear resistance and also increase hardness in order to prolong the service life. The powder variations utilized were 5%, 10% and 20% Si, with the balance being pure titanium powder. The following process parameters were investigated: Laser power, scanning speed and powder flow rate. Results showed increase in wear rate and microhardness with increasing silicon content. It was also found that a lower laser power (1.2 kW), a medium scanning speed (0.45 m/min) and a higher powder flow rate (6 g/min), resulted in the achievement of the highest hardness. Thus, process parameters are key determinants in microstructural development and material properties for engineering applications.
    Keywords: Ti-Si coatings; laser parameters; Hardness; Wear rate; Ti-6Al-4V alloy; laser cladding.

  • Micro-structural and hardness study of stir-casted AZ91D/B4C MMCs   Order a copy of this article
    by Sakshi Singh, Nathi Ram Chauhan 
    Abstract: This paper investigates the effect of the amalgamation of reinforced based metal matrix composites by using vacuum-based stir casting process. AZ91D Mg alloy is the matrix material and B4C with varying volume ratio fractions (2, 4, and 6%) act as reinforcement. For microstructural observation, specimens have been machined, polished and then etched. Vickers macro hardness has been evaluated under room temperature. The improvement in macro-hardness has been found in reinforced B4C/AZ91D MMCs as compared to cast-AZ91D Mg alloy. The microstructural study reveals the enhancement in homogeneity of AZ91D MMCs due to the addition of B4C reinforcement. The heterogeneous formation of alpha-Mg matrix and Mg17Al12 has been found to be dominant in form of dendrite-like three-dimensional branches. The reduction in porosity and voids (microstructural defects) have been observed in B4C/AZ91D MMCs as compared with cast-AZ91D Mg alloy.
    Keywords: AZ91D Mg Alloy; matrix; boron carbide particles; reinforcement; Scanning electron microscope; hardness; and phases etc.

  • Characterization of Ferric oxide reinforced magnesium nano-composites processed through microwave sintering/powder metallurgy   Order a copy of this article
    by Balasundar P, Narayanasamy P, Srikrishna Ramya S I, Ramkumar T, Senthil S 
    Abstract: Magnesium nano composites reinforced with 0.5, 1 and 2 wt.% of nano Fe2O3 particles were blended-hot pressed-microwave sintered powder metallurgy technique. The morphological characterizations of Mg and nano Fe2O3 were performed using scanning and transmission electron microscopy respectively. The elemental characterizations of powder particles were done using Energy Dispersive Spectroscopy analysis. Physical properties such as density and porosity were calculated as per ASTM standards. The microwave sintered samples were studied in terms of its micro hardness. The fabricated nanocomposites have been characterized structurally by optical microscope. The hardness of the nano composites was significantly increased, to increase the nano Fe2O3, and also the results establish that the study signify that the proposed method is an effective energy saving for preparing the nanocomposites with extremely denser and enhanced micro hardness, highly homogeneous and uncontaminated microstructure.
    Keywords: Nano-composites; Fe2O3; microwave sintering; Microstructure.

  • Microstructure evaluation and modelling the tensile strength and yield strength of titanium alloys   Order a copy of this article
    by P.S. Noori Banu, S. Devaki Rani 
    Abstract: The rationale of the current study was to develop artificial neural network models of titanium alloys for predicting tensile strength and yield strength using the alloy composition and processing parameters as the inputs and validate the models through experimental evaluation and correlate with microstructure characteristics. The robustness of the model was tested through experimental evaluation of tensile strength in Ti-6Al-4V, Ti-5.8Al-4Sn-3.5 Zr-0.7Nb-0.5Mo-0.3 Si, Ti-3Al-8V-4Zr-6Cr-4Mo, and Ti-10V-2Fe-3Al alloys. Microstructure characteristics i.e. volume fraction of alpha, alpha grain area and Feret ratio of Ti, Ti-6Al-4V, Ti-6Al-5V, Ti-6Al-6V-2Sn, Ti-8Mn, and Ti-13V-11Cr-3Al correlated inversely with predicted tensile strength and yield strength. This three-tier validation ensures efficient performance of the developed ANN models.
    Keywords: Titanium alloys; artificial neural network; microstructure; volume fraction alpha; alpha grain area; Feret ratio.

  • Reliability Studies on Biaxially Tensile Strained-Si Channel p-MOSFETs   Order a copy of this article
    by Sanghamitra Das, Tara Prasanna Dash, Suprava Dey, Rajib Nanda, C.K. Maiti 
    Abstract: An integrated technology computer aided simulation framework is used for the first time to predict the reliability (degradation) of substrate-induced strained-Si channel heterojunction field effect transistors on relaxed Silicon-Germanium buffer layer with ultra-thin SiO2 and high-k gate stacks. State-of-the-art four-state nonradiative multiphonon model is used for the degradation studies. Single defects and trap studies have been taken up on devices subjected to negative voltage stressing at an elevated temperature. Threshold voltage shift (due to charge capture and emission processes) in virtually fabricated devices has been studied in detail. For the first time, non radiative multiphonon model is used to explain the degradation mechanisms (oxide defects dominating the partial recovery of threshold voltage after stressing) in strained-Si channel heterojunction field effect transistors. It is shown that degradation in strained-Si channel device on relaxed-SiGe buffer is more compared to its Si-channel counterpart.
    Keywords: Reliability; degradation; non-radiative multiphonon model; biaxial strain; strained-Si; relaxed-SiGe; oxide defects.

  • ANALYSIS OF THE MECHANICAL PROPERTIES AND PENETRATION DEPTH OF GAS METAL ARC WELDING ON AISI 304 STAINLESS STEEL   Order a copy of this article
    by Taiwo Abioye, Oyeyemi Gbadeyan, Damilola Adebiyi 
    Abstract: The microstructure, penetration depth and mechanical properties of gas metal arc weldments of AISI 304 stainless steel were investigated within a process window. 9 weldments were produced using Taguchi L9 orthogonal array technique. Well bonded, crack- and pore-free weld joints were obtainable at wire feed rate of 66-96 mm/s, voltage of 19-25 V and welding speed of 5.0-9.6 mm/s. The weld joint hardness (305-395 HV) decreased with increasing the heat energy input. However, weld penetration depth (2.67- 4.86 mm) increased as the heat energy input increased. Full weld penetration was achieved at heat energy value of 519 J/mm. The ultimate tensile strength (UTS) first increased with increasing the heat energy input until an optimum value of 765
    Keywords: MIG welding; Stainless steel; Tensile strength; Micro-hardness; microstructure; weld penetration depth; Taguchi technique; wire feed rate; voltage; welding speed; heat input.

  • Influence of initial oxidation and secondary oxidation on spontaneous combustion of lignite   Order a copy of this article
    by Zhi-an HUANG, Ling-hua ZHANG, Rui YANG, Ying-hua ZHANG, Hui WANG, Yu-yan CHEN, Yukun Gao 
    Abstract: In order to prevent the re-ignition of residual coal, this study presents a study of initial oxidation and secondary oxidation on the spontaneous combustion characteristics of coal. Three physical experiment methods:pore volume analysis, Fourier transform infrared spectroscopy and cross point temperature method, were used to study the spontaneous combustion of lignite. The results show that the pore volume of coal increases with the increase of oxidation temperature. With the increase of temperature, different functional groups in the coal sample show different trends. Compared with initial oxidation, the tendency of the functional group changes again during the secondary oxidation. In the case of constant initial temperature of secondary oxidation, the crossing point temperature of coal samples show a decreasing trend at first and rising later. And in the case of constant initial temperature of initial oxidation, the crossing point temperature of coal samples show a trend of rising.
    Keywords: coal spontaneous combustion; pore volume; functional group; crossing point temperature.

  • Effect of Input Parameters on Friction Stir Processing of AA2014-T6 using Response Surface Methodology   Order a copy of this article
    by Jacob John, S.P. Shanmuganatan, M.B. Kiran 
    Abstract: The friction stir processing is governed by input process attribute like spindle speed, traverse feed, tilt angle and geometry of the tool. In this study, five different shapes of the tool are selected to carry out the process. Response surface methodology adopting Central Composite Design has been used as a statistical approach to generate the regression models in order to envisage and estimate ultimate and yield tensile strength of the processed sample. The results indicated that the values predicted by experimentation are in good accordance with the estimated outcome. The objective of this paper is to study the influence of input parameters and geometry of the tool on the tensile strength of the friction stir process. It has been noticed that the input parameters exhibit significance effect on tensile strength and the tool having hexagonal profile yields better strength than the other selected geometries.
    Keywords: AA 2014-T6; Friction stir processing; Tensile strength; Response surface methodology; Analysis of Variance.

  • CRACKING PERCEPTION OF MACHINE COMPONENTS WITH SOUND EMISSION DURING STEEL QUENCHING   Order a copy of this article
    by Franc Ravnik, Janez Grum 
    Abstract: Quenching and tempering often represent a stage near the end of the manufacturing process ofrnmachine components. The purpose of selecting the most suitable quenching parameters andrncontrolling the hardening process is to ensure the required hardness and the residual stresses,rnparticularly in the surface layer of a machine part. This is most important in mass production,rnin which the best mechanical properties are required in order to obtain the lowest cost and thernbest quality. This paper includes the investigation of certain acoustic events during steelrnquenching. The possibility of understanding the relation between a connection between soundrnemission with the wetting kinematic of the quenching agent and a hot specimen with otherrnphenomena during quenching was examined. It was determined that the captured acousticrnsignals could identify the suitability, i.e. the quality of the quenching process to ensure betterrncontrol of the quenching process. For this purpose, a system with a hydrophone was designedrnto capture acoustic emissions. An investigation of sound emission was carried out with a fewrncylindrical specimens, i.e. different shapes made of heat-treatable steel quenched in quenchingrnagents with different cooling severities. Furthermore, the possibility of acoustic signals causedrnby workpiece deformation and crack formation due to high internal stresses were examined. Arncomparison of results shows that this possibility can lead to an applicability approach torncontrolling the hardening process and quality of steel parts.
    Keywords: cooling rate; cracking; nucleate boiling; sound emission; quenching.

  • Analysis on the Effect of Pressure and Mass Fraction of Chromium to Mechanical Properties and Electrical Conductivity of Copper-Chromium Composite in Hot Compaction Process   Order a copy of this article
    by Dicki Nizar Zulfika, Widyastuti Widyastuti, Lukman Noerochim, Nanda Hendra Pratama, Subardi Marjali, Irwin Maulana, Radyum Ikono, Nurul Taufiqu Rochman 
    Abstract: Cu-Cr composite is used in the electronic industry as a material which is directly connected to the electricity, as a component of a circuit breaker, cable contact, circuit board, etc. In this study, hot compaction method was employed to manufacture Cu-Cr composite which has an excellent hardness and electrical conductivity. Composite manufacturing was based on powder metallurgy technique while mixing used mechanical milling method in regards to its better homogeneity. Hot compaction process set at the temperature of 300 oC was applied to the powder material to increase the plasticity so the compaction can be done easier. Some variation were made on the composition of Cu:Cr ratio (90:10, 80:20, 70:30, and 60:40), and the compaction pressure (500, 700, and 1000 MPa). Sintering was conducted at 850 oC with holding time of 1 h. Based on the results, the optimum sintering density of 96.81% of its theoretical density was obtained at Cu:Cr ratio as of 80:20. Maximum hardness at 60%Cu:40%Cr and P= 1000 MPa was 129 VHN. And, electrical conductivity was reached its optimum value of 82.6% IACS when the Cu:Cr ratio was 90:10 at P= 1000 MPa.
    Keywords: Cu-Cr; Hot Compaction; Composite; Powder Metallurgy.

  • Research on hysteretic behavior of high-strength concrete shear wall plate for steel tube in building construction   Order a copy of this article
    by Zhongwei Liu 
    Abstract: For the problem of insufficient analysis of the hysteretic behavior of the traditional concrete shear wall, the research method of hysteretic behavior of high-strength concrete shear wall for steel tube in building construction is proposed in paper.Based on the OpenSee platform,the displacement of the base was recorded by the displacement meter installed on the base, and the load displacement curve is plotted, and the shear bearing capacity of the model was analyzed. The failure modes, axial compression ratio and concrete strength parameters of the specimens were studied to obtain the following conclusions. Higher the axial compression ratio and the wall shaft pressure, the higher the load capacity of the specimen. By comparing the hysteretic behavior of different steel tube high strength concrete shear strength specimens, this paper analyzes the performance of steel tube high strength concrete shear wall panels, which provides data and reference for future construction.
    Keywords: Building construction; steel tube; high-strength concrete; shear wall; hysteretic behavior.

  • Characterization of LM6/cenosphere composites   Order a copy of this article
    by Tanusree Bera, Samir Kumar Acharya, Goutam Sutradhar 
    Abstract: In this work, the LM6/cenosphere composites were fabricated by the squeeze casting. The various weight percentages of cenosphere (wt. % c/s) (5, 7.5, 10, 12.5, and 15) wt. % c/s were selected for the synthesis of the LM6/composites. The characterization of the reinforced and unreinforced composites through SEM, XRD, and EDX analysis was carried out. The mechanical properties (hardness, and tensile strength) were investigated. The optical properties were investigated through FTIR and UV-VIS-NIR. The results revealed that the reinforced LM6/cenosphere composites show better mechanical properties than the unreinforced composites. The 15 wt. % composites show the improved hardness and tensile strength with minimum porosity as compared with other reinforced composites. The XRD analyzed the various phases of the materials. The EDX analyzed the atomic and the wt. % of reinforced elements exists in the LM6/cenosphere composites. The SEM analyzed the tensile fractured surfaces of the reinforced and unreinforced composites.
    Keywords: LM6 alloy; Cenosphere; Squeeze casting; Mechanical properties,Fractography; Optical properties; X-rays Diffraction; Scanning electron microscope.

  • Parametric Optimization of Gas Metal Arc Dissimilar Welding on AISI 304 Stainless Steel and Low Carbon Steel   Order a copy of this article
    by Taiwo Abioye, Chibueze Kanu, Tunde Ogedengbe, Damilola Adebiyi 
    Abstract: The weld-bead geometry and mechanical properties of the AISI 304 stainless steel and low carbon steel gas metal arc dissimilar weldments were optimized within a process window (wire feed rate (66-96 mm/s), voltage (19-25 V) and welding speed (3-6 mm/s)). The variations of the weld-bead width and mechanical properties with the processing parameters were analyzed and presented. Significant changes in the microstructure of the weld zone with the heat energy inputs were observed. All the three utilized parameters contributed significantly to the bead width, ultimate tensile strength and hardness of the weldments. The welding speed contributed most significantly to the ultimate tensile strength and bead width while the voltage has the most significant effect on the hardness. Optimum weld qualities including continuous joint, high tensile strength (422 MPa) and high hardness (112 HB) were found at 84 mm/s wire feed rate, voltage of 25 V and speed of 3 mm/s.
    Keywords: Gas metal arc welding; Optimization; Dissimilar metals; Full factorial design; ANOVA; Mechanical properties; AISI 304 stainless steel; Low carbon steel; Microstructure; Heat energy input.

  • Contribution to thermal study of modified cement pastes based on siliceous SCMs.   Order a copy of this article
    by KARIMA ARROUDJ, Mohamed Nadjib OUDJIT, Arezki TAGNIT-HAMOU 
    Abstract: This study aims to highlight siliceous additions available in Algeria : ground blast furnace slag
    Keywords: Pozzolanic activity; Portlandite; Hydration degrees; DTA/TG; SEM; XRD.

  • WATER ABSORPTION BEHAVIOUR AND ITS EFFECT ON THE MECHANICAL PROPERTIES OF Gigantochloa scortechinii (BULUH SIMANTAN)   Order a copy of this article
    by Abeer Adel Salih 
    Abstract: This study aims to investigate the effect of short-term exposure of water to the mechanical properties of simantan fibres at different heights. Few studies have investigated the mechanical properties of raw natural fibres after water absorption. Bamboo culms were cut at 15 cm above the ground level and then subdivided into bottom, middle and top parts according to their total length. The raw fibres were immersed in distilled water at room temperature for different time durations (6, 24, 48, 72, 96, 168, 336, 504 and 672 h). Tensile, flexural and impact properties were examined before and after water absorption, the tensile fracture of raw fibres were observed by scanning electron microscopy, and the structure properties of raw fibres were examined by Fourier transform-infrared spectroscopy. The result showed that 6 h of immersion time exhibited the best tensile strength and modulus, showing 13.6% and 28% improvement compared with the dry condition. The optimum flexural strength and modulus were 240 MPa and 13.7 GPa, respectively, for the top part under dry condition. The impact strength for the bottom part after 672 h of immersion in water was 212 KJ/m2, which was very close to that under dry condition. SEM revealed that the main destruction is due to the lack of uniform breakage of fibres due to blanks and water absorption. Overall results clearly showed that immersion in water for a short time minimally affected tensile strength, modulus and flexural modulus but considerably influenced flexural strength and impact properties.
    Keywords: microstructure; material properties; water absorption; bamboo fibres; natural fibres; mechanical properties; buluh simantan; bamboo culms; uniform breakage of fibres.

  • Microstructure Assessment of Bi-modal Microcellular Polymeric Composites developed using Multi-Stage Depressurization Technique in Solid-State Foaming Technology   Order a copy of this article
    by Abhishek Gandhi, Rajesh Panda 
    Abstract: In this study, bimodal microcellular acrylonitrile butadiene styrene foams have been manufactured through solid-state batch foaming process using two staged gas depressurization technique. After blowing agent saturation, the thermodynamic instability induction on polymer/gas system due to instantaneous pressure drop was performed at two distinct depressurization stages. Each stage corresponded to nucleation of discrete cell morphology in the polymer matrix. This article puts forward a study to understand the fundamental mechanism behind bi-modal cell nucleation phenomenon. Further, Influence of holding time, holding pressure, foaming temperature and foaming time on the foam morphological attributes was studied. By altering the process parameters, the morphological attributes in the final product could be controlled efficiently.
    Keywords: microcellular; microstructure; morphology; bimodal; foam; cells; composite.

  • Characterization of self-healing efficiency of calcium nitrate microcapsules for concrete applications   Order a copy of this article
    by Ala Abutaqa, Mohammed Al-Ansari, Ahmed Senouci, Marwa Hassan, Ahmed Shaat, Mohamad Mohsen 
    Abstract: This study presents characterisation of concrete samples containing 0.75% by cement weight of modified calcium nitrate self-healing microcapsules. The phased array ultrasonic testing method was used to investigate the healing efficiency of calcium nitrate microcapsules in concrete. The method is a novel non-destructive testing technique that is commonly used for detecting the defects in welding. Concrete beams were prepared from the control mix (without microcapsules) and mixes containing 0.75% by weight of cement of calcium nitrate microcapsules. After 28 days of moist curing, the phased array ultrasonic images of all beams were captured before loading, after applying 60% of the ultimate flexural load, and after 3 and 7 days of accelerated healing. Moreover, scanning electron microscopy images taken from fractured surfaces of the beams that were loaded up to failure before healing were compared to those of the beams that were healed for 7 days and loaded up to failure
    Keywords: Calcium nitrate microcapsules; self-healing concrete; calcium nitrate microcapsules; phased array ultrasonic testing; scanning Electron Microscopy.

  • Effect of Duty Cycle on Microstructure, Composition and Ablation Resistance of Tungsten-Cobalt Coatings Prepared by Electrodeposition   Order a copy of this article
    by Haipeng LU, Junqi QIN, Changchun DI 
    Abstract: Tungsten-cobalt coatings with different tungsten contents were prepared on the surfaces of PCrNi3MoVA steels by electrodeposition at different duty cycles. Scanning electron microscope (SEM) with energy dispersive spectrometer (EDS) and X-ray diffractometer (XRD) were used to analyze the effect of duty cycle on the microstructure and composition of the surface and cross-section of tungsten-cobalt coatings before and after ablation. The ablation performance was measured using a self-developed semi-closed explosive ablation tester. The results show that the CoW phase mainly exists in the tungsten-cobalt coating before the ablation. The tungsten content in the coating increases first and then decreases with the increase of the duty cycle. When the duty cycle is 30%, the tungsten content is the highest (43.37wt%). The grain size increases with the increase of the duty cycle. The grain size of the coating obtained at the 10% duty cycle is the smallest (9.70 nm); The tungsten-cobalt coating mainly contains CoW, WO3, CoO, SiO2, Fe3O4 and a small amount of CoWO4 phase after the ablation. The sample prepared at the duty cycle of 30% has the best ablation resistance, and its relative mass ablation rate and relative line ablation rate are 0.08% and 0.89%, respectively. The effect of duty cycle on ablation resistance of the tungsten-cobalt coating is mainly achieved by affecting the tungsten content and the grain size in the coating. Higher tungsten content and denser crystal, the ablation resistance of tungsten-cobalt coating is better . The ablative mechanism of the tungsten-cobalt coating is a combination of thermal chemical ablation of tungsten-cobalt coating oxidation, thermal physical ablation of melting and evaporation of oxidation products, and mechanical ablation of high-temperature and high-pressure propellant gas.
    Keywords: Pulse electrodeposition; Tungsten-Cobalt coating; Duty cycle; Tungsten content; Ablative properties.

  • Structural, optical and galvanomagnetical properties of low cost synthesized nanostructure Cu2S films   Order a copy of this article
    by Abdelfatah Mansour, Emad El-Menyawy 
    Abstract: The cu2s powder was prepared by low-cost hydrothermal method and was deposited as thin films by thermal evaporation. The structural properties are explored by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The XRD shows a monoclinic polycrystalline nature of hydrothermally prepared powder, while the deposited film shows a hump corresponding to Cu2S nanocrystallites. HRTEM micrograph shows nanoparticles with sizes ranging from 30 to 45 nm. Based on the thermogravimetric results, the thermal kinetic parameters are calculated by application of Broido method. The optical energy band gap of the evaporated films is determined as 2.3 eV. The electrical conductivity, charge carriers concentration, carriers mobility and the magnetoresistance (MR) of the films are investigated as a function of temperature.
    Keywords: Copper sulfides; Hydrothermal; Thermogravimetric; Optical; Galvanomagnetic; Conductivity; Carriers concentration; Mobility; Magnetoresistance.

  • SYNTHESIS AND CHARACTERISATION OF Sb-DOPED ZrO2 AND TiO2 NANOPARTICLES   Order a copy of this article
    by ASHA PAI 
    Abstract: The present study aims at the synthesis and structural characterisation of Sb-Doped Titania and Zirconia nanoparticles using a modified precipitation synthesis method. The produced nanoparticles were characterised using various techniques such as UV-Visible spectroscopy, Scanning electron microscopy, Transmission electron microscopy and Dynamic light scattering. The crystallite sizes were obtained to be <20 nm for Sb-Doped ZrO2 and <10 nm for Sb-Doped TiO2 which was very evident from the Transmission electron microscope images. The hydrodynamic sizes in the range of 100 nm using Dynamic light scattering method were also evaluated for the assessment for biological application. The optical band gap was found out to be 3.21 eV for Sb-Doped TiO2 and 3.87 eV for Sb-doped ZrO2.
    Keywords: Zirconia; Titania; X-ray diffraction; Doping; precipitation synthesis; Transmission electron microscopy; Scanning electron microscopy; dynamic light scattering.