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The present investigation deals with development of AA2219 composites with different weight fractions of Cerium oxide (CeO2) reinforcement and characterizing the microstructure and mechanical properties thereof. XRD and SEM micrograph confirm the presence of CeO2 particles and Al2Cu precipitate. The grain size of 0, 0.5, 1.0, 1.5 and 2 wt% CeO2 composites are 483, 453, 411, 362 and 328 μm, respectively. Addition of CeO2 significantly reduces the dendritic morphology and refines the α-Al grain structure. 2 wt% CeO2 addition has yielded the maximum hardness of 124 HV and yield strength of 87 MPa in all the composites developed. Additionally, the developed composites were evaluated by examining the wear characteristics with the co-efficient of friction (COF) and the specific wear rate. In this study, Taguchi's L25 orthogonal array was used to optimize the parameters like reinforcement fraction, load and sliding distance. Signal-to-noise ratio (S/N ratio) and analysis of variance (ANOVA) are used to obtain the parameters highly influencing the wear behaviour. Adhesive wear is exhibited by ploughing at lower loads and delamination is observed with increasing load. Deep shallow ploughs with embarked abrasion are observed at higher loads.

The commercially pure magnesium (Mg) was successfully processed through equal channel angular pressing (ECAP) at a set of warm temperature and back pressure up to four passes in different routes. The microstructural, mechanical and wear behavior has been investigated with respect to the number of passes and the processing route. The samples have displayed substantial grain refinement, improved mechanical properties and wear resistance after the ECAP process. The fractographs of tensile samples confirmed fracture mode as a ductile–brittle mixed fracture. The X-ray line profile analysis demonstrates that modifications in the microstructure after ECAP contribute to the improved mechanical properties. The sample processed in route BC exhibits improved mechanical and wear properties owing to its refined microstructure and maximum microhardness.

This work is to optimize the back pressure (BP) and processing temperature required for equal channel angular pressing (ECAP) of commercially pure magnesium. ECAP was performed at different processing temperatures with different back pressures for one pass. For a combination of back pressure and processing temperature the crack-free samples were obtained. Microstructural characterization of pure magnesium samples after ECAP was performed using an optical microscope and mechanical behavior is discussed with hardness and tensile test results. From the XRD peak profiles, the microstructural feature such as crystallite size, micro-strain and dislocation density are analyzed using the modified Williamson and Hall (W-H) method. The results concluded that the processing temperature of 200 °C and back pressure of 150 MPa is the best combination of processing parameters to process crack-free pure magnesium by ECAP.

In-spite of many advantages of Al-Si alloys, it is limited in industrial application due to lack of ductility, because microstructure contains plate like Si particles which is embedded in an Al-matrix. This article describes the modification effect on microstructure and mechanical properties of sodium modified hypoeutectic Al-Si alloys. Modification has been done by using pure Na as modifier with different composition 0.08, 0.12 and 0.16 wt% at 10, 15 and 20 min holding time on hypoeutectic Al-Si alloy. Microstructure of modified samples has been analyzed by optical microscope and eutectic particle size was measured by using ImageJ software. In all cases the modified microstructure has shown the fine fibrous eutectic particle which is uniformly distributed throughout the sample. Tensile and hardness test were carried out by tensometer and Vickers hardness testing machine and the properties were studied. The fracture surface analysis was carried out by SEM. Due to modification, eutectic particle size has reduced and mechanical properties have improved.

The effect of weave pattern on the mechanical properties of basalt- reinforced epoxy composite was investigated. Basalt in the plain and twill weave fabric forms were used for reinforcement, and lapox (L-12) epoxy resin was used as the matrix. Different weave types and their effect on mechanical properties of the weave were considered in the present study. The composite laminate was fabricated by the compression molding technique. Mechanical tests including tensile, compressive, and hardness tests were conducted as per the ASTM standards. Plain weave composites exhibited better mechanical properties compared with twill weave composites. From the results, it was evident that the weave pattern of the fabric significantly influences the strength of fibre reinforced composites.

This study aims at studying the dynamic mechanical and thermogravimetric properties of boron carbide (B4C) filled carbon fiber (CF)/epoxy composites (BC-CF/Ep composites) using the wet lay-up process assisted by vacuum bagging technique. The B4C fillers were used in varying filler weight percentages (1%, 3% and 5%) in the different CF/Ep composites and are uniformly mixed in epoxy system through ultrasonification process and was used as the matrix. The Toray make bidirectional twill (2 × 2) woven T800CF was used as the reinforcing material. The Dynamic Mechanical Analyzer (DMA) and Thermogravimetric Analysis (TGA) tests are conducted to study the dynamic capacity and thermal degradation behavior respectively. In the DMA, the storage modulus (E1), loss modulus (E11), damping behavior (Tanδ) and glass transition temperature (Tg) of CF/Ep composite specimens are studied with increasing temperature from (25–173)°C. The BC1% composites showed better storage modulus, loss modulus and damping factor, while unfilled CF/Ep and BC3% composites showed better Tg than other CF/Ep composites. As far as TGA is concerned, the BC1% composites exhibited better thermal stability than all other composites. The dynamic tests resulted in the trend of BC1% > unfilled CF/Ep > BC3% > BC5% composites. The TGA tests also followed the trend of BC1% > unfilled CF/Ep > BC3% > BC5% CF/Ep composites.

The present work investigates the influence of delta wing vortex generators placed inside circular mitred pipe bends, handling high density and erosive coal slurries. Coal slurry flowing at different Reynolds numbers ranging from 2000

This research focuses on the static mechanical, thermal and tribological properties of carbon fibre epoxy (CF/Ep) composites filled with boron nitride (BN) micro-filler powder (BN-CF/Ep). The mechanical properties studied were tensile, flexural, interlaminar shear strength and hardness. The thermal properties studied were dynamic mechanical and thermogravimetric analyses which were analysed through dynamic mechanical analyser and thermogravimetric analyser, respectively. The curing ability and dispersion of BN filler in the Ep and composites were investigated through differential scanning calorimetry, Fourier-transform infrared spectra and scanning electron microscopy. The tribological properties focused were three-body abrasion and dry sliding friction and wear conduct. Three-body abrasion tests were studied with silica sand of 212 µm particle size, 30 N load, 2.38 m s−1 sliding velocity and variable abrasive distances of 250 m, 500 m, 750 m and 1000 m. The dry sliding wear tests were performed using pin-on-disc (POD) wear experimental set-up with 60 N load, 3 m s−1 sliding velocity and variable sliding distances of 1000 m, 2000 m and 3000 m. The results followed the trend of BN1% > BN3% > BN5% composites in all mechanical properties. The carbon fabric reinforcement along with the BN-Ep matrix improved enormously all the mechanical properties except impact resistance. Further, it was exhibited that 1 wt% BN into CF/Ep prompts better mechanical properties with predominant damping capacity and thermal stability. Both the dry sand abrasive wear and POD test outcomes revealed that all BN-CF/Ep composites prompt predominant wear resistance. CF along with BN improves enormously the wear resistance with friction coefficient. Further, it was exhibited that 1 wt% BN into CF/Ep in both three-body abrasive and POD tests prompts better wear resistance. Generally speaking, it was presumed that BN-CF/Ep gracefully and successfully improved the mechanical, thermal and tribological properties and morphology of Ep for various mechanical, electrical components and load-bearing applications used in automotive and engineered applications.

Cavitation erosion corrosion of AA7075 CNT Hybrid GrP nano Composite is dealt in this paper. Since we know that AA7075 is manufactured for aerospace, automobile industries as a structural material. The need of the hour to strengthen this in manifold. To find the erosion corrosion resistance of such an alloy, was made by compo casting (Stir-Squeeze) are commonly used for the production of components, such as cylinders, pistons, pumps, valves and combustion chambers, which in service may experience a cavitation phenomenon. Microstructure, Hardness, mechanical properties were measured. Cavitation tests were carried out according to ASTM G32 standard and the erosion mechanism was examined by optical microscope and Scanning Electron Microscope. It was found the both CuCNT/CuGrP particles enhances and diminishes cavitation erosion resistance in a particular combination of the two, which is expressed in terms of mass loss, and also galvanic coupling between these particle with matrix behaves differently when it is corrosion. Both the effect are studied simultaneously to see the synergetic effect on different combination of CuCNT/CuGrP particles with AA7075.

The role of metal matrix composites (MMC) has gained huge momentum in the various research as well in the industrial application due to its high stiffness and high strength to weight ratio. It helps in achieving enormous weight reduction without compromise in the strength of the material. In this study, a novel attempt is made to fabricate MMC with martensitic stainless steel as matrix and titanium diboride (TiB2) as reinforcement. The AISI 420 matrix with different weight percentage (0%, 1%, 2%, and 4%) of TiB2 reinforcement was fabricated by vacuum induction melting technique. The fabricated composite was subjected to X-ray diffraction (XRD) study which revealed the presence of TiB2 phase as well as its respective crystal structure. The microstructural characterization of the AISI 420/TiB2 composite was done. Optical microstructure reveals the presence of secondary phase reinforcement in a homogeneous manner inside the matrix and also across the grain boundaries. Scanning electron microscopy (SEM) images further ensure the availability of TiB2 in the matrix. The hexagonal morphology in the SEM ascertains the TiB2 presence. Energy dispersive spectroscopy (EDS) spectrum shows the presence of the T and B elements in the appropriate weight and atomic percentages. Microhardness results of the composite show that the hardness value increases with the more addition in the wt% of TiB2 particles. The overall results confirm that the AISI 420 metal matrix composite with TiB2 reinforcement can be effectively synthesized by casting route. The addition of TiB2 enhances the hardness of the composite significantly

The present article deals with reinforced AA7075 CuCNT/CuGrP Hybrid nano Composite. To find the corrosion resistance of such an alloy composites, was made by compo casting (Stir- Squeeze) are commonly used for the production of components, such as cylinders, pistons, pumps, valves and combustion chambers, which in service may experience a corrosion phenomenon. Initially different percentage of microstructure, hardness, and mechanical properties were measured. Corrosion tests were carried out according to different mass fraction of copper coated CNTs and copper coated GrP was added to the AA7075 casting and the composition is optimised. The electrochemical corrosion behaviour of CuGrP and CuCNT reinforced AA7075 were studied using Electrochemical Polarization Technique (ACM Gill) and Electrochemical Impedance Spectroscopy Technique. The phase analysis of the composites were done by XRD, microstructure by optical microscope even severity of corrosion is measured optical microscope. The corrosion behaviour of the composites and the possible mechanism for the effect of CuCNT and CuGrP in the properties have been studied in detail in this paper.

The present work compares the numerical fluid dynamic and wall erosion characteristics of a single phase fluid flowing through two vertical pipe bend assemblies: sharp (S) and mitred (M). Both the ‘S’ and ‘M’ pipe bend assemblies have circular section with double bends each having a 90° flow turning angle. The ‘S’ bends has a single weld joint and the ‘M’ bends were made of 2 pieces of miter segments, thus having three weld joints. Single phase fluid (water) was made to flow at five Reynolds numbers 1e5

The aim of this paper is to investigate the mechanical properties of Nickel Aluminium Bronze (NAB) alloying with Niobium (Nb) and Yttrium (Y) rare earth metals. NAB alloy frequently used in the aqueous solution as well as less widely used deployed materials were studied. To avoid failures due to aqueous environment. Niobium (Nb) and Yttrium as chosen alloying addition with NAB. The Nb and Y rare earth element which acts as stabilizing element to existing NAB system to optimize the mechanical properties. The NAB with alloying elements processed in the vacuum induction furnace by means of predetermined parameters. After casting, the samples were tested for the mechanical properties like tensile and Brinell hardness to ensure improvements with the master NAB system. At the same time, the characterization techniques SEM and EDAX with mapping analysis confirmed the chemical proportions of the elements in the developed NAB with proposed NAB (Nb) and NAB (Y) alloys. A comparative study is to be made for the NAB with Nb and Y under aqueous environment based for the developed alloys.

Rare earth oxide reinforced Aluminium matrix composite are produced using La2O3 as dispersoids in VAL12 aluminium alloy matrix by varying the percentage of dispersoids. The composites are tested for their microstructural evolution and mechanical properties. Advanced characterization techniques are used in characterizing the composites to reveal the microstructural and physical properties. The microscopic examination reveals refinement in grain structure with increasing reinforcement percentage of La2O3. XRD results shows peak broadening of matrix and increase in the intensity of dispersoids peak confirming the presence of reinforcement in the matrix. Energy dispersive spectrum mapping further confirms the elemental composition of the composites. The actual density of the composites are more than 95% of the theoretical density as the squeeze casting process produces with very less porosity level. The tensile test results show loss of ductility in the composites having dispersoids more than 4% (by wt.) which was further elucidated with the fractographic and machining studies. Fractographic results show fracture propagating in both matrix and reinforcement as there is good interface between matrix and reinforcement. The machining studies on developed composites reveal continuous, semi continuous and disintegrated chips, revealing increase in brittle nature with respect to increase in dispersoids percentage.

The influence of crystalline nature of aluminium in mechanical properties of carbon Nanotubes (CNT) reinforced Aluminium alloy is reported. The materials chosen for this study is AA 4032 alloy powders and multi-walled Carbon Nanotubes (MWNT). Three different composites were prepared by powder metallurgy technique. First is an AA4032/MWNT microcrystalline composite, second one is AA4032/MWNT nano-crystalline composites and third one is AA4032/MWNT bimodal composites. The microcrystalline structure was prepared by regular P/M route where nano-crystalline and bimodal structure was prepared by mechanical alloying. The micro-hardness and compressive strength of different composites were measure and analyzed.

Cast hyper duplex stainless steel (HDSS) was modified with a stabilizer Niobium to suppress the formation of deleterious intermetallic phases. Based on the Thermo calc, samples were heat treated at 900 °C and 1150 °C. Intergranular corrosion resistance was studied with the help of double loop electrochemical potentiokinetic reactivation (DL-EPR) method. Surface of the specimen was characterized by optical microscope, SEM coupled with EDS. Addition of niobium retards the formation of chromium carbides and the same was confirmed with EDS point analysis. DL-EPR shows the better degree of sensitization for niobium stabilized cast HDSS than the regular HDSS.

The conventional copper alloys with regular grain structure and size are relatively low yield soft materials. To overcome this limitations of conventional tin bronze monolithic material to achieve good combination of strength, along with stiffness, toughness and density, current work focuses on the development of composites using boron carbide particulates as reinforcement. Boron carbide was chosen as a particle reinforcement for composite material for its high hardness, high melting point, low density, with high elastic modulus (448 GPa) and chemical properties. The composites are tested for its mechanical properties and correlated with the microstructural morphological changes using advanced microscopic techniques. The tensile test results shows on increasing percentage of reinforcement, the ductility of the composites is lost. The composites show, microstructural refinement and formation of intermetallic phases, at the grain boundaries justifying increases in the hardness and tensile strength of the as cast composite.

Rare earth oxide reinforced Aluminium matrix composite are produced using La2O3 as dispersoids in VAL12 aluminium alloy matrix by varying the percentage of dispersoids. The composites are tested for their microstructural evolution and mechanical properties. Advanced characterization techniques are used in characterizing the composites to reveal the microstructural and physical properties. The microscopic examination reveals refinement in grain structure with increasing reinforcement percentage of La2O3. XRD results shows peak broadening of matrix and increase in the intensity of dispersoids peak confirming the presence of reinforcement in the matrix. Energy dispersive spectrum mapping further confirms the elemental composition of the composites. The actual density of the composites are more than 95% of the theoretical density as the squeeze casting process produces with very less porosity level. The tensile test results show loss of ductility in the composites having dispersoids more than 4% (by wt.) which was further elucidated with the fractographic and machining studies. Fractographic results show fracture propagating in both matrix and reinforcement as there is good interface between matrix and reinforcement. The machining studies on developed composites reveal continuous, semi continuous and disintegrated chips, revealing increase in brittle nature with respect to increase in dispersoids percentage

An investigation has been performed on the slurry erosion behavior of squeeze cast AA7150 aluminium alloy – a potential structural alloy in as cast condition. The tests were conducted at room temperature varying the service factors using quarts silica sand. The cast samples were examined for its metallurgical and mechanical factors followed by investigation on erosive wear behavior. The results showed the ductile nature of mechanism undergone and greater influence was seen with respect to the angle of impingement. The erodent flow rate also significantly affects the performance of the material. The surface morphologies of the wear tested specimens were examined using SEM for better understanding on the mechanism of failure. Severe plastic deformation is seen in all the cases as the strain energy exceeded the elastic strain rate.

This article reviews the current state of the art in understanding manganese steels. The standard manganese steel (Hadfield’s Manganese) has roughly 12% manganese and 1.2% carbon. This approximate 10 to 1 ratio from Hadfield’s work. Then there is High manganese steels with 18–31% Mn with higher carbon content upto 1.9%, higher manganese grades require elevated carbon levels in order to achieve the desired increase in service life. And other being Lean manganese steels with 5–8% Mn, 1%C and 1.5%Mo to help stabilize the austenite. Medium Mn steels had been investigated due to their excellent balance between material cost and mechanical properties. Consisting of a single α′ martensite phase in hot and cold rolled states and multiphases after inter-critical annealing. The steels exhibit high strength and good ductility due to transformation induced plasticity occurring in retained γ γR, whose volume fraction is approximately 0.2–0.4. There another deformation mechanism called twinning induced plasticity (TWIP) enhances certain Manganese steels. TWIP steels exhibit very high strain hardening rate due to the deformation twins taking advantages of dynamic Hall-Petch effect. In TWIP steels the manganese content varies between 20 and 30%. In spite of some very desirable properties, it also poses a challenge in materials production. Reducing Mn content in TWIP steels and addition of Al reduced the tendency for delayed cracking. Since the Mn content in TWIP steels influences the stacking fault energy (SFE) which plays major role deformation mechanism. This review concludes by suggesting fundamental research needs to promote the design of manganese steels with improved properties and performance.

SS321 is used as the electrolyte reservoir to store potassium hydroxide electrolyte. The metal is prone to get corroded at the electrolyte environment. The present work is carried out for minimizing the corrosion of SS321 potassium hydroxide electrolyte reservoir which is a part of the AgO-Zn reserve primary battery by passivation with citric acid. The uniqueness of the present work exhibits the optimization of passivation method and process conditions, to withstand concentrated alkaline (KOH) medium stored in SS321 electrolyte reservoir, which is having a long life of more than 7 years. Polarization and KOH resistance tests suggest that AISI 321 showed excellent passivation studies behavior when treated with citric acid solution. Hence it is necessary to establish the corrosion behavior of SS321 electrolyte storage container in alkaline solution by electrochemical studies. The thickness loss and weight loss are the main parameters measured to quantify the amount of corrosion. The Voltammetry and AFM studies established the minimum corrosion rate by passivation process method. Based on the results of electrochemical studies and anodic polarization experiments, it was confirmed that the passivation layer formed by treating the material with Citric acid, is capable of improving the corrosion resistance of stainless steel significantly and the passive film is more stable than those produced by other passivating methods. Thus, to minimize the rate of corrosion on electrolyte storage container for the period of battery life of more than 7 years, citric acid passivation having a good corrosion resistance in concentrated alkaline electrolyte (KOH) medium, is best suited and the method of treatment involved is benign & environment friendly.

The main aim of this study was to get a better knowledge of mechanical properties of carbon fabric reinforced epoxy (CF/Ep) composites. The selected mechanical properties of the CF/Ep composite with different fiber architectures (T300CF/Ep, T700CF/Ep and T800CF/Ep) are investigated for indentation, in-plane, tensile and bending loads. All composites were fabricated with equal weight percentage of carbon fiber and similar consolidation process using hand layup procedure followed by compression moulding method. Experimental results showed that the effect of fiber weave structure on mechanical properties of the CF/Ep composites is more obvious than that in neat epoxy. Both tensile and flexural results showed that high strength carbon fiber (T800) has evident strengthening effects on the tensile and bending load response of CF/Ep composites. The fiber architecture marginally affects the density and severely affects strength and deformation of composites. T300CF/Ep and T800CF/Ep composites are nearly linear up to final brittle fracture while T700CF/Ep system exhibit non-linearity before failure. Furthermore, it is seen that composite performance is dictated by inherent properties of carbon fiber and weaves structure. Even with fiber flaws, stress concentrations, the weaving pattern is beneficial because it makes composites to be very less subtle to flaws. These characteristics are addressed systematically with consideration of numerical aspects of fibers strength and critical defects formation. The significant developments in the mechanical properties of composite systems are further assisted using scanning electron microscopy

The basic property of corten steel is its ability to create a protective layer on its surface in unfavorable environments. This protective layer protects the steel without an anti-corrosion coating. But owing to water accumulation in passenger coaches near lavatory areas and different climatic conditions especially in high chloride conditions, the protective layer formation is not possible leading to premature failure due to accelerated corrosion. In this work, the corrosion resistance of polyurea coatings compared with present coating was studied on corten steel. The coated steel is subjected to immersion and salt spray test and the corrosion rate are evaluated based on ASTM B117 Standards. The corrosion resistance of coating was assessed by monitoring the polarization resistance of the coated steel immersed in 3.5% wt of NaCl solution. The profilometry of the samples were also done to elucidate the enhancement of corrosion resistance of coated steel.

This research work based on carbon fiber epoxy (CF/Ep) composites shows the effect of Boron carbide B4C filler on mechanical properties using a hand layup procedure followed by the vacuum bagging process method. The boron carbide fillers were uniformly dispersed in epoxy resin and used as matrix material. The weight percentage of (B4C) filler material in the composite was varied and mechanical properties were obtained with microfiller. The T800CF/Ep composites with 1%wt., 3%wt. and 5%wt. B4C fillers were taken for evaluating the mechanical properties. All composites were fabricated with an equal weight percentage of carbon fiber and a similar consolidation process. The mechanical properties like tensile properties, flexural properties, Interlaminar shear strength, impact strength and hardness are studied to know how the mechanical response of composite structures varies with filler addition. Testing followed the trend of 1%wt. > 3%wt. > 5%wt. of B4C in all mechanical properties of B4C filled CF/Ep composites. Tensile strength of 1%wt. B4C filled composites were better than basic CF/Ep composites whereas 3%wt. & 5%wt. B4C filled composite values were lower. The tensile modulus of all the B4C filled composites was better than basic CF/Ep composites. Flexural properties of 1%wt. and 3%wt. B4C filled composites were better than basic CF/Ep composites whereas 5%wt. B4C filled composite values were lower. Interlaminar shear strength (ILSS) of 1%wt. B4C composites gave better results whereas 3%wt. and 5%wt. B4C filled composites gave lower results. The impact energy of all composites gave lower values than basic CF/Ep composites. Hardness values of all B4C filled composites were better than basic CF/Ep composites. The most important developments in the mechanical properties of composites are further supported by scanning electron microscopy.

Air receivers in railway coaches usually come under severe degradation due to exposure to external atmosphere and corresponding climatic changes. IS 2062 Steel is used for this application. Frequent cleaning and replacement become part of the process. Polymer based coating can save this material from corrosion and subsequent wear. In this work poly urea coating was carried out on an IS 2062 steel. The corrosion properties of the coating were studied using potentiodynamic polarization test in ASTM standard 3.5%NaCl solution. The corrosion resistance of coated material was compared with the base material. The depth of corrosion of the samples were studied to evaluate the enhancement of corrosion resistance of coated IS206. The poly urea coating enhances codal life of these material by manifold.

This research paper based on bidirectional carbon fiber/epoxy composites (CF/Ep) shows the effect of fiber architecture on mechanical properties using a hand layup procedure followed by the vacuum bagging process method. The three different fiber architectures T800CF/Ep, T700CF/Ep and T300CF/Ep were chosen for studying the mechanical properties. All composites were fabricated with an equal weight percentage of carbon fiber and a similar consolidation process. The tensile properties, flexural properties, interlaminar shear strength, impact strength and hardness are studied to know how the mechanical response of composite varies with fiber architecture. Testing results showed that the effect of fiber weave architecture is more obvious in CF/Ep composites than in neat epoxy with regard to mechanical properties. Both tensile and flexural properties showed that T800CF/Ep composites have a very good strengthening effect on both tensile load response and bending load response of CF/Ep composites. The fiber architecture has less effect on the density and serious effect on the strength and deformation of CF/Ep composites. Inherent properties and weaves structure of carbon fiber (CF) dictated the performance of composites. Compared to Hand layup method, the Vacuum bagging method showed (2–6)%, (11–15)%, (5–6)%, (15–20)% and (1–3)% improvement in tensile strength, tensile/flexural modulus, ILSS, impact strength and hardness respectively whereas the flexural strength values were almost near to the former values Grunenfelder et al. (2017). The most important developments in the mechanical properties are further assisted by scanning electron microscopy.

An investigation was carried in Nickel Aluminium Bronze (NAB) alloyed with Niobium (Nb) and Yttrium (Y) to study the effect of the microstructure for onshore applications. Nickel Aluminium Bronze is broadly used in aqueous atmospheres due to their good mechanical and corrosion resistance properties. The presence of destructive species in aqueous water initiates the corrosion of the engineering modules is inevitable. In-order to optimize the corrosion resistance Nb and Y were added as (1%, 2% & 3%) respectively in the master NAB. The specimens were exposed to the immersion test in NaCl solution. To create the behavior of corrosion and succeeding erosion, altered immersions hours were selected as 8, 16, 24, 32, 40, 48 and 54 h. The mass loss measurements were obtained after the completion of the individual specified time to calculate corrosion rates (CR). Solid particle erosion (SPE) investigations were also carried out on the developed alloys. The size of the particle which is used in the investigation is 50 µm. Corrosion rate was calculated and it is correlated with the immersion time. Scanning electron microscopy (SEM) investigations were observed for the corroded and eroded specimens.

The present work compares the flow characteristics of a single phase fluid flowing through two vertical pipe bend assemblies: sharp (S) and mitred (M), using CFD. Both the ‘S’ and ‘M’ pipe bend assemblies have circular section with double bends each having a 90° flow turning angle. The ‘S’ bends has a single weld joint and the ‘M’ bends were made of 2 pieces of miter segments, thus having three weld joints. Water was made to flow at five Reynolds numbers 1e5

Metallic corrosion is a major concern for bogie side frames used in railways. The exposure to harsh environment is unavoidable and a protective coating is one possible solution. In this work, tungsten-based carbide coating was produced on EN10025/5 steel. The corrosion properties of the coating were studied using potentio dynamic polarization test using actual field conditions and using ASTM standard 3.5% NaCl. The coating was subjected to slurry exposure using waterjet erosion tester. The microstructure of the eroded area was studied for understanding the wear mechanism. The corrosion and erosion of the coating was compared with the base material. It was evident that tungsten-based carbide coating increases the corrosion and erosion resistance of steel in railway application.

Duplex stainless steels (DSS) exhibit excellent corrosion resistance and mechanical properties to the severe environments and hence are used in many engineering applications such as oil and marine industries, chemical storage, nuclear power plants, and many more. These are used as valves, fittings, and pipes to suck the crude oil in oil fields. Austenite (γ) and ferrite (δ) phases constitute the microstructure of DSS. However, one needs to control both the phases towards making it lucrative in desired applications. Investigations on tribological behavior of cast DSS are limited. The current work focuses on optimizing the wear parameters for slurry jet erosion and analyzing their effect on wear of the 5A DSS. Grey relation analysis (GRA) and Taguchi design of experiments have been used for optimization. Slurry jet erosion tester was used investigate the response of the material to various designed experiments. Worn-out surfaces morphologies and wear mechanisms were revealed using Scanning electron microscopy (SEM), whereas white light interferometer was used to understand 3D morphologies the surfaces.

La2Ti2O7 nano metric powder was prepared using solid state route and evaluated in the present study. Precursors of lanthanum oxide and titanium dioxide were blended, synthesized at 850 °C for 8 h. The phase analysis of the synthesized powder was carried out using XRD diffraction analysis to check the purity of the perovskite La2Ti2O7 compound formed. The crystalline size measurement was carried out using Debye–Scherrer formula which reveals that the synthesized powder at 850 °C for 8 h is in the range of 49.54 nm. The powder morphology was studied using the SEM and EDS result confirms the presence of La, Ti and O elements. The SEM results reveal irregular morphology of the powders and few clusters which may be attributed to the presence of the moisture in them.

AlCoCrNi alloy was modified by adding Mo to increase its corrosion resistance. Mo was successfully added to the alloy using mechanical milling. All the five constituents of the alloy were milled in a high-energy planetary ball-mill for 20 h. The effective concentration of Mo in the alloy was 10%. At equal intervals, samples were taken for phase formation studies using X-ray diffractional analysis (XRD). The micro-structural characterization was carried out to confirm the homogeneity of the alloy using Field emission scanning electron microscopy (FESEM). The resultant high entropy alloy (HEA) powder was thermally sprayed over a 316l substrate using High-velocity Oxy-fuel (HVOF) technique. Corrosion characteristics of the coating were studied using potentio-dynamic polarization (PDP) test under standard condition. The corrosion properties of the coating were compared with conventional NiCrSiB corrosion resistant coating. The AlCoCrMoNi HEA system offers better resistance to corrosion than NiCrSiB coating.

Nanocrystalline powders of 4 mol.% GdO1.5-4 mol.% SmO1.5 doped ZrO2 (4Gd4SmSZ) has been synthesized by co-precipitation process. Their phase transformation and crystalline growth behavior was investigated by Thermo gravimetric-Differential Thermal Analysis (TG-DTA), X-ray Diffraction (XRD), Raman spectroscopy and High-Resolution Transmission Electron Microscopy (HR-TEM) after calcinations at different temperatures. The XRD, Raman spectra and HRTEM results confirm the nature of tetragonal zirconia (t-ZrO2). The prepared 4Gd4SmSZ powders, remains in the single metastable tetragonal phase over the whole calcination temperature ranging from 873 K to 1273 K for 2 h. The crystallite size varies from 11.98 nm to 18.90 nm with increase of temperature from 873 K to 1273 K. The activation energy of the prepared powders at low temperature is considerably lesser than that at a higher temperature. The annealed 4Gd4SmSZ powders had shown excellent phase stability at 1573 K for 100 h. Keywords: Zirconia, Coprecipitation, Rare earth oxide, Phase transformation, Tetragonal, Activation energy

The effect of ZrO2(2, 4, 6 and 8 wt%) dispersoids with 1 wt% graphite on the microstructural, mechanical properties on squeeze cast VAL12 matrix hybrid composite is investigated in the present study. The hybrid composites were characterized using advanced characterization techniques to reveal its microstructural and physical properties. The microscopic examinations using optical and SEM technique reveal that the addition of dispersoids accelerates the nucleation kinetics, thus attaining fine, equiaxial grains in hybrid composites. The squeeze cast composites show almost nil porosity, defects and owing to it, the actual density of the composites are found to be more than 95% as that of the theoretical density values. The hardness values and tensile values increase with respect to the increase in percentage addition of ZrO2. The tensile results show that there is an appreciable increase in the UTS values of composites without much loss in its ductility as the addition of graphite improves the self-lubricating property and provides wettability during the casting. Fractographic studies on tensile tested specimen reveal that the crack occurs in both matrix and particles showing the good interface between matrix and dispersoids. Machinability studies reveal the formation of continuous chips in hybrid composites with a lower percentage of reinforcement (up to 4% ZrO2+ 1%Gr) and segmented chips in case of the composite with 8% ZrO2+ 1%Gr, as the increase in the percentage of dispersoids improve the chip breakability of the composites. On an overall, the hybrid aluminium matrix composites with 1%Gr and 6 % ZrO2unveiled better optimal results.

Mg-9Li-3Al magnesium alloys with varied level of Nd added (i.e., 0-2.0wt. %) alloys were prepared electric resistance stir casting furnace under controlled inert gas atmosphere. Impact of Nd addition on metallographical changes and mechanical characteristics of as-cast alloys were analyzed by using an OM, XRD, SEM with EDS. The metallography evaluation revealed that adding Nd refines the microstructures due to formation of Al2Nd and Al11Nd3 precipitates, these precipitates exists together with α-Mg, β-Li, AlLi, MgLi2Al phases in the alloy. Furthermore, adding Nd improves the mechanical strength and elongation. 1.5wt.% Nd added alloy displayed the better mechanical characteristics; UTS is 166MPa; Elongation 16.87%.

Dissimilar welding of 3mm thickness of AISI 304L austenitic stainless steel plate and AISI 430 ferritic stainless steel plates were performed by Tungsten Inert Gas welding without any filler material by using argon as shielding gas. Welding is carried out according to set of combinations of welding parameters such as welding current (levels of 135,140,145 Ampere), welding speed (levels of 105, 110, 115 mm/min) and shielding gas flow rate (of levels 5,10,15 Litre/min) obtained through Taguchi L9 orthogonal approach for maximizing the ultimate tensile strength by using MiniTab software . Radiography test was performed to know the soundness of the welds. Tensile specimens are fabricated as per ASTM E8 standard for tensile testing. Microstructural observations of the weld are performed. Correlations have been obtained to know the effect of welding speed, welding current and shielding gas flow rate on tensile strength and an optimum level of parameter is obtained at welding current of 145 Ampere, welding speed of 115 mm/min and shielding gas flow rate of 5 Litre/min.

The effect of cerium addition on AZ91 magnesium alloy and its influence on stress corrosion cracking (SCC) were studied using constant load proof ring testing NaCl-K2CrO4 and ASTM D1384 solutions at 70 and 80% of yield stress, respectively. The investigation revealed that the optimum grain refinement of desired phases occurred with 0.5% addition of cerium. The addition levels of cerium above 1.5 wt.% to AZ91 alloy resulted in premature failures due to poor SCC resistance in both solutions (K2CrO4 and ASTM D1384 solutions). The microstructural studies of the experimental alloys were characterized by using optical and scanning electron microscopy. The elemental compositions of cerium-added AZ91 magnesium alloys were studied by energy-dispersive spectroscopy. The results indicate that the mode of SCC failure was found to be transgranular in nature along with secondary cracks containing cleavages which resulted from the hydrogen embrittlement and anodic dissolution phenomena. The AZ91 alloy with 0.5 wt.% cerium exhibits better mechanical properties and high stress corrosion resistance.

Nickel-based superalloys are used widely in the critical areas of applications such as aerospace, marine, power and many process industries. In this study, solid particle erosion behavior of cast nickel-based CY5SnBiM was analyzed at room temperature. The velocity and angle of the study were set to 59 m/s, 92 m/s and 124.137 m/s, and 30°, 45°, 60° and 90°, respectively; this resembles the exact industrial valve applications. Macrographs were taken to identify the wear scar of material at different angles and different velocities. X-ray diffraction (XRD) was carried out on the material to observe the nature of precipitates. Scanning electron microscopy (SEM) was carried out to identify the plowing action on the material by the erodent in the case of lower angle due to ductile nature of the material. In the case of higher angle, it develops deep pits and craters due to rebounding of erodent particles.

As-cast Mg-9Li-3Al-xNd (x = 0-2.0 wt.%, with the variation of 0.5wt.%) magnesium alloys were prepared through casting in electrical induction melting furnace under a controlled inert gas atmosphere. Influences of Nd over the metallography changes and corrosion characteristics of Mg-9Li-3Al alloys have been examined by following techniques are OM, XRD, SEM and potentio-dynamic polarization (PDP) test. The results illustrate that adding Nd modifies the continuous β-Li phases into discontinuous phase by the formation of new precipitates such as Al2Nd and Al11Nd3. Meanwhile, the grain sizes of Mg-9Li-3Al-xNd alloys reduced with respect to the increasing Nd content. PDP results disclose that the Nd addition reduces the corrosion current density (icorr) of Mg-9Li-3Al alloys which can be essentially produced by grain refinemente.

In this present research, the coatings of SA209-T1 using high velocity oxygen fuel were employed for the application of boiler tubes. Due to the adaptation of corrosion easy in boiler material, the research of those properties is significant because of its criticality and functionality during the service time. A right coating was found and applied on the SA209-T1 surface against corrosive environments. Good corrosion resistance is achieved by WC-flyash coatings applied on SA209-T1 substrate. The 90% WC-10% flyash coatings were found to be more protective followed by SA209-T1 steel. WC-flyash covering was tracked down so that the covering is compelling to secure the SA209-T1 steel substrate. It is reasoned that the arrangement of NiO, Cr2O3, CoO, and NiCr2O4 could add to the advancement of consumption opposition in coatings. The steel of uncoated endured erosion as extraordinary stripping and spalling of the scale, which could be because of the development of Fe2O3 oxide scale unprotectively. This paper reveals the performance, applications, and development of 90wt.% WC and 10wt.% fly ash through HVOF coating in SA209-T1 for electrochemical corrosion studies at room temperature.

Aluminium composite with VAL12 as matrix and La2O3 as dispersoids fabricated through liquid metallurgy route involving liquid forging operation through squeeze casting process in the present investigation. The frictional characteristics of as-cast aluminium composites are studied under dry sliding wear tests by varying the service factors. The samples prepared were examined for its uniform distribution of the reinforcement, phases formed using advanced characterization facilities. Taguchi orthogonal array method is employed in designing the experiments, and the responses are recorded in terms of wear rate and frictional coefficient. The mechanistic studies are carried out by analyzing the wear surface morphology using SEM. Predominantly AMMC shows delamination and abrasion at higher loads due to thermal softening and adhesive mechanisms at lower loads. Load and sliding distance majorly characterize the wear behavior of the AMMCs under un-lubricated sliding conditions.

This research focuses on the tensile properties, dynamic-mechanical and thermogravimetric analysis of carbon fibre-reinforced epoxy (CF/Ep) composites with graphene nanoplatelets (GnP) nanofiller (G-CF/Ep). These composites were portrayed regarding tensile properties, surface morphology, dynamic-mechanical and thermogravimetric analysis. The dynamic-mechanical properties studied were storage modulus, loss modulus, dynamic capacity and glass transition temperature (Tg) through the dynamic-mechanical analyser. The thermogravimetric property studied was weight loss% through the thermogravimetric analyser. The carbon fabric reinforcement along with the GnP-Epoxy matrix improved the tensile properties. Further, it was exhibited that 1.75 wt% GnP into CF/Ep prompts predominant damping capacity and thermal stability. Generally speaking, it was presumed that GnP-filled CF/Ep composites even with very small wt% GnP gracefully and successfully improved tensile, dynamic-mechanical and thermogravimetric properties as well as the morphology of epoxy for various engineered applications.

Duplex stainless steel (DSS) is having an equal fraction of ferrite and austenite. Chromium, Nickel, Molybdenum, and few minor alloying elements constitute a DSS system, which makes metallurgy of the system complex. Proper heat treatment is need of the hour when it comes to expecting desired properties from the material, subjected to a specific working environment. DSS is one of the favourite choices for oil and gas industries. This study focuses on optimizing the heat treatment parameters and heat treating the as-cast 5A DSS and investigating microstructural evolution of the material subjected to various quenchants such as brine, water, and polyethylene glycol. Heat treatment temperatures, quenching media, and the quenching time have been selected in accordance with ASTM standards. Thermocalc TCFE8 database is being used for understanding the material response to various heat treating temperatures.

Niobium addition to base alloy significantly reduces the formation of deleterious phases, in particular, sigma phase when the material is sensitized at 900 °C. In this paper, hyper-duplex stainless steel with 0.47% of Niobium (Nb + CD3MWN - 7A) was casted using induction melting furnace and then heat-treated under two different heat treatment temperatures of 1160 °C and 900 °C to explore the properties such as microstructure and hardness for further study. The erosion test was carried out in air-jet erosion tester at room temperature with different erodent velocities. The study was done with a constant impact angle of 45°. Microstructure analysis was carried on two different heat-treated samples as well as on eroded samples using scanning electron microscope coupled with energy-dispersive analysis spectroscopy to confirm the presence Niobium carbide precipitation in sensitized sample at grain boundaries. Erosion test results showed that erosion rate is lower in sensitized sample when compared to solutionized sample because of their higher hardness in sensitized sample.

Carbon nanotubes (CNT) are synthesized using arc discharge method in an open air. Various amounts of carbon nanotubes-reinforced AA7075 composites are prepared by powder metallurgy route and then hot extrusion at 450 °C. Hot-extruded composites are characterized, and mechanical properties are measured. Dry sliding wear properties of hot-extruded samples were evaluated using a pin-on-disk method for various loads (5-20 N) at room temperature and for various temperatures (100-400 °C) at the applied load 10 N as a function of CNT amount. Grain size of the composites is decreased compared with Al alloy matrix. Transmission electron microscopy of the composites revealed that the CNT are uniformly distributed in the composites. Mechanical properties of the hot-extruded composites are enhanced with an increase in CNT content. The wear performance is improved with an increased CNT amount, but decreases with an increase in the applied load and temperature as well. The wear damage is mild at lower applied loads and temperatures, whereas the damage is severe at 400 °C. The wear mechanism was plowing in the initial stages which is transformed to severe sliding and chipping with increasing load and temperature. The enhanced wear behavior of composites is attributed to self-lubricating nature of carbon nanotubes.

High cost imported components of seamless steel tube manufacturing plants wear frequently and need replacement to ensure the quality of the product. Hard chrome plating, which is time consuming and hazardous, is conventionally used to restore the original dimension of the worn-out surface of the machine components. High Velocity Oxy-Fuel (HVOF) thermal spray coatings with NiCrBSi super alloy powder and Cr3C2 NiCr75/25 alloy powder applied on a 50CrMo4 (DIN-1.7228) chromium molybdenum alloy steel, the material of the wear prone machine component, were evaluated for use as an alternative for hard chrome plating in this present work. The coating characteristics are evaluated using abrasive wear test, sliding wear test and microscopic analysis, hardness test, etc. The study results revealed that the HVOF based NiCrBSi and Cr3C2NiCr75/25 coatings have hardness in the range of 800–900 HV0.3, sliding wear rate in the range of 50–60 µm and surface finish around 5 microns. Cr3C2 NiCr75/25 coating is observed to be a better option out of the two coatings evaluated for the selected application.