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Islands-Matrix-Dual-phase (I-M-DP) steel is received a great deal attention for better concern with the emissivity, fuel consumption and passengers safety. A number of deformation plasticity issues are yet to be fully understood. Complex deformation stages for various stain is predicted as the natural outfall of the plastic strain localization caused by the ill-assorted deformation between the martensite-island phase and the ferritic-matrix phase. Modeling is carried out both in macro level by bending under tension (BUT) for different roller radius/sheet thickness ratios to acquire strain and stress state deformation and micro scale by Representative Volume Element (RVE) according to element position. It can relate both the 2D, 3D micro and macro scale finite element based BUT model’s result of flow behavior. Systematically strain based severe deformation pattern arises from outfall of plastic strain localization and von Mises stress distribution in island-matrix steels are investigated on the microstructure by finite element method for ill-assorted deformation between phases.

The conflicting traffic volume (CTV) is one of the crucial parameters for the estimation of U-turn capacity at a mid-block median opening (MBMO). Therefore, in this work, CTVs at MBMOs were estimated. A simple yet practical methodology was developed and a parameter called the spatiotemporal conflict factor was introduced. In order to estimate the spatial conflict factor, the entire carriageway width was divided into two zones – the spatial conflict zone and the spatial no-conflict zone. Spatial conflict factors were estimated by studying the placement characteristics of approaching through traffic and U-turning traffic. Subsequently, temporal conflict factors were estimated based on the no-conflict time gap and possible slowdown sections. The spatiotemporal conflict factors and the resulting CTVs were then calculated for MBMOs in six-lane and four-lane roads. The tangible outcome of this investigation is the ability to estimate the realistic capacity values of median openings, which will be beneficial for traffic planners in the efficient management of traffic for improved levels of service and safety.

Among the various surface modification processes, the hot-dip aluminizing process has increasingly evoked considerable attention. This method has proved to be commercially cost-effective and technically better than galvanizing. In contrast to hot-dip aluminized steel components, galvanized components cannot be used in service conditions at elevated temperatures. During the last few years, intensive research by researchers has yielded new insights into metallurgical aspects of aluminized coating in as-dipped and annealed condition. The present review gives a bird’s eye view of the hot-dip aluminizing process, from the early years of its inception to the current research on aspects of the aluminized coating. The progress of research on thermodynamic studies, phase equilibria, phase identification, and their crystallographic features have been traced in this attempt. This review is not restricted to briefing the research performed so far but also points out several issues of discrepancies among the results of the published literature. Special emphasis has been given to the phase development in the coating during annealing and the increasing horizon of application of hot-dip aluminizing to alloy steels in hot stamped conditions. Reference has also been made to state-of-the-art topics embracing the current research on computer simulation software and sophisticated experimental techniques. However, lower surface hardness and economy restrict the wide application of the hot-dipping process.

Sintered boron carbide is an extremely hard, structural ceramic material and it is difficult to be machined with conventional techniques. To overcome the machining problem, the spark plasma sintered (SPS) monolithic boron carbide (B4C) was successfully machined by wire electrical discharge machining (WEDM) as the material is electrically conductive. The effects of five different machining parameters of WEDM were carefully observed to check their effect on the useful responses, namely machining speed and surface roughness (Ra) for cutting sintered B4C samples. A number of experimental operations were derived by using the concept of central composite design (CCD) and fuzzy logic was implemented to predict the response for a particular input parameter set. Also, a multi objective optimization was performed by fuzzy logic rule based multi performance characteristics indices technique (MPCI).

Unconventional wire electrical discharge machining (WEDM) process is successfully used to cut different metals, alloys, composites and recent addition is engineered ceramics which possess sufficient electrical conductivity. Boron carbide is one of the hardest ceramic materials that unable to be processed with conventional machine tools and can be machined by WEDM compulsorily with proper selection of machine parameters. This study is based on boron carbide samples which were prepared using spark plasma sintering (SPS) furnace and machined with WEDM. Five machining parameters were analyzed such as pulse on time, pulse off time, peak current, water pressure and servo feed rate. Surface roughness (Ra) and machining speed were considered as output parameters and design of experiment was derived using central composite design (CCD) of response surface method (RSM) with 32 numbers of different test runs. Adaptive neuro-fuzzy inference system (ANFIS) was used with a new set of 16 numbers of experiments to predict results and seen to be more reliable than predicted results of response surface method.

Interstitial-free (IF) steel specimens were coated by hot-dip aluminizing process bearing bath composition as Al-6.9% Si-1.4% Mg and bath temperature at 800 °C. Dipping time varied for 0.5, 1, 3 and 6 min. The objective of the present study is to conduct a systematic investigation to identify and analyse the formation of various phases and compounds in the coating. Studies on aluminizing of steel had indicated the presence of an intermetallic layer adjacent to steel substrate. In this study, the morphological features obtained after hot dipping at 800 °C were investigated. For the application of aluminized steel sheets in industry for manufacture of tubes and pipes, the adherence of the aluminized coating must be ensured. This property of the coating is influenced by the morphological features of the coating. Aluminizing being thought of a possible substitution of galvanizing owing to its promise to evolve lesser volume fraction of intermetallic phases and consequently known to generate a ductile coating. The entire coating consists of an outer Al-Si topcoat and a thin intermetallic layer which composed of an outer θ-FeAl3 and inner η-Fe2Al5 layers. The thickness of intermetallic layers was found to increase with the increase of dipping time in a near parabolic manner.The phases formed on the IF steel substrates were characterized by scanning electron microscopy with EDS, X-ray diffraction, EPMA and EBSD techniques.Interesting findings from XRD include the presence of Al3FeSi2 (τ4) and Al2FeSi (τ3) phases, which normally appear after annealing of aluminised sheet. A distinct elemental Si peak was found in XRD study. Presence of Mg in the form of Mg2Si was also found in XRD and supported by EPMA investigation. Presence of several ternary Al-Fe-Si (τ3, τ4, τ5) and binary FeAl3 and Fe2Al5intermetallic phases were identified by composition profile analysis from SEM based EDS and GDOES and further confirmed by EBSD. Presence of Si humps in the top and intermetallic layer attributed by the presence of Si-bearing phases or elemental pro-eutectic Si in Al-Si alloy were also indicated in SEM-EDS and GDOES study. Variation of surface topographical features of the HDA steel substrates with increasing dipping durations were examined and reported for the first time by using AFM. Formability tests were conducted by bending the samples 180° over a mandrel. None of the specimens showed any tendency of flaking exhibiting excellent bonding of the coating with IF steel substrate.

Electrical conductivity is an essential property for machining of sintered boron carbide especially by wire electrical discharge machining (WEDM) process. Pure boron carbide was spark plasma sintered to full density at 2050 °C. Rietveld refinement on XRD analysis confirmed presence of B13C2 as the major phase in the powder as well as in the sintered samples.Electrical conductivity was found to be ~48 Ω−1m−1. The sintered specimens were successfully machined using WEDM technique. The microstructure of powder, machined and fractured surfaces of the sintered boron carbide were analyzed. At low power of WEDM with pulse current less than 140 A formation of molten, oxidized phases of boron carbide was observed as well as the development of surface cracks were minimum on the machined surface. Thus this work is aiming at achieving better product quality with sintered boron carbide specimens which are machined by WEDM.

This study discusses the experimental investigation on WEDM of EN AW 7075 alloy deformed severely plastically by Equal Channel Angular Extrusion (ECAP). Experimentation has been executed by varying pulse-on time (Ton), pulse-off time (Toff), peak current (IP) and spark gap voltage (SV). The influence of these parameters was studied on the kerf width (KW), machining speed (MS). The set of machining parameters for experiments were prepared using central composite design (CCD) followed by response surface methodology (RSM). Optimization was carried out using Genetic algorithm. From machining performance analysis it can be inferred that longer pulse-on time which causes greater discharge energy, affects the most on the response parameters, hence leading to a higher amount of material removal causes an increase in machining speed and kerf width.

Introduction: Hyponatremia is a serious adverse event in the paediatric critical care population is especially complex as many patients require multiple continuous infusion and excess uid volumes due to hypovolemic shock or blood pressure instability. Aim & objective:To detect hyponatremia among patients admitted in medical icu of agmc & gbph and to study its etiology. Objectives 1. To nd out the proportion of patients admitted in icu having hyponatremia. 2. To study the etiology of hyponatremia in these patients. Material & methods: One year starting from 1st Nov 2019 to 31st October 2020. All the patient admitted in the ICU; age more than 18 years, size was depend on the total admission within the study period in General Medicine, Murshidabad Medical college and R. G. Kar Medical college, West Bengal. Conclusion: We found that most common age group 41-60. It was found that male were predominance than female. It was found that 96(27.9%) patients had Hyponatremia We found that 22(6.4%) patients had Euvolemia, 49(14.2%) patients had Hypervolemia, 25(7.3%) patients had Hypovolemia and 248(72.1%) patients had normal.

Introduction: Hepatic encephalopathy is a frequent complication and one of the most debilitating manifestations of liver diseases, severely affecting the lives of patients. Aims and objective: i. To study the precipitating factors of hepatic encephalopathy. ii. To observe the clinical manifestation at the time of presentation of hepatic encephalopathy. iii. To observe the seasonal variation of hepatic encephalopathy in cirrhotic patient. Materials and method: General Medicine, Murshidabad Medical college and R. G. Kar Medical college in West Bengal. All adult cirrhotic Patients admitted with encephalopathy in the medicine ward within the study period. One year starting from 1st Nov 2019 to 31st October 2020. Conclusion: This study found that most common precipitating factors of hepatic encephalopathy in our patients are infection, constipation electrolyte imbalance and Variceal Haemorrhage bleeding. These are potentially preventable and reversible.

In this work, the Spark plasma sintering technique has been used to sinter ZrB2-B4C (20 wt%) composite at 2100 °C and 50 MPa uniaxial pressure for 15 min soaking in an argon atmosphere. XRD analysis has been carried out on the sintered sample to analyze the different phases present in the ZrB2-B4C composite. The Rietveld refinement technique has been used to analyze the crystal structure, the unit cell information such as space group, cell position, cell angles and atomic distances of the composite material using FULLPROF software.

The cyclic plastic deformation of an archetypal microstructure dual phase steels has been examined via micromechanics modelling based on representative volume elements technique. The dual phase steel has soft ferrite – matrix with hard martensite – islands, which are distributed in a discrete manner. In the field of automobile industries, the suitable combination of strain hardening, strength and ductility, and their lean combination represent them as an economically desire option for huge multiple lightweight options. In this numerical approach, different microstructures for micromechanical modelling were constructed to detailed examination and analysis for the tensile and cyclic deformation response of dual phase steels. Due to the distinct difference in the stress–strain responses of ferrite and martensite phases, incompatibility of strain between matrix-softer ferrite and island-harder martensite phase arises during tensile straining. The effect of strain partitioning in cyclic plastic deformation response of dual phase steel has been studied in the present investigation. Apart from this, effect of martensite volume fraction on cyclic stress–strain response of dual phase steels, cyclic plastic deformation distribution in individual phases and cyclic deformation inhomogeneity at microstructural level have been systematically investigated. Keywords: Cyclic plastic deformation, Dual phase steel, Martensite volume fraction, Plastic strain localization, Stress triaxiality, Material inhomogeneity

In this paper, using equivalence, we classify the error correcting linear codes of length 5 and dimension 2 over GF(3). We are able to show that these codes can be partitioned into 3 mutual...

The surface scaling behavior of nanostructured Cu thin films, grown on glass substrates by the pulsed laser deposition technique, as a function of the deposition time has been studied using height–height correlation function analysis from atomic force microscopy (AFM) images. The scaling exponents α, β, 1/z and γ of the films were determined from AFM images. The local roughness exponent, α, was found to be ∼0.86 in the early stage of growth of Cu films deposited for 10 minutes while it increased to 0.95 with a longer time of deposition of 20 minutes and beyond this, it was nearly constant. Interface width w (rms roughness) scales with depositing time (t) as ∼ tβ, with the value of the growth exponent, β, of 1.07 ± 0.11 and lateral correlation length ξ following ξ = t1/z and the value of 1/z = 0.70 ± 0.10. These exponent values convey that the growth dynamics of PLD Cu films can be best described by a combination of local and non-local models under a shadowing mechanism and under highly sticking substrate conditions. From the scaling exponents and power spectral density function, it is concluded that the films follow a mound like growth mechanism which becomes prominent at longer deposition times. All the Cu films exhibited SPR properties where the SPR peak shifts towards red with increasing correlation length (ξ) whereas bandwidth increases initially with ξ and thereafter decreases gradually with ξ.

To forecast the plastic strain and flow behaviour of DP steel, a Bending under Tension (BUT) simulation and a micromechanical modelling based accession by aid of a Representative Volume Element (RVE) was engaged. The strain deformation behaviour is attained by applying macroscopic modelling of an orthodox Bending-Under-Tension (BUT) model. A consecutive microscopic modelling was enforced by acknowledging arbitrary phase distribution of close to practical microstructure by 2D RVE. Affinity amid microscopic behaviour and macroscopic (BUT model) comprising strain and stress distribution, were extracted from edge region RVE modelling. The macro-micro modelling prospective inflates the impression of steel microstructure, which will facilitate the microstructure to be implemented for numerous utilization in automobile industry.

An inclusion generates a stress concentration and it plays a crucial role both damage evolution and mechanical response of materials. In the current work, the stress fields around hard and soft circular inclusions are analytically determined within the framework of the linear theory of elasticity. The Kirsch's solution is here modified for the case of a hard or a soft inclusion, by applying both the theory of superposition and equi-energy stress partition criterion. The presented approach is validated by finite element simulations by considering with six different hard and soft inclusions.

Growth dynamics of thin films expressed by scaling theory is a useful tool to quantify the statistical properties of the surface morphology of the thin films. To date, the growth mechanism for 2D van der Waals materials has been rarely investigated. In this work, an experimental investigation was carried out to identify the scaling behavior as well as the growth mechanism of 2D MoS2 thin films, grown on glass substrates by pulsed laser deposition for different deposition time durations, using atomic force microscopy images. The growth of MoS2 films evolved from layer-by-layer to layer plus island with the increase in deposition time from 20 s to 15 min. The film surface exhibited anisotropic growth dynamics in the vertical and lateral directions where RMS roughness varied with deposition time as w ∼ tβ with the growth exponent β = 0.85 ± 0.11, while the lateral correlation length ξ was ξ = t1/z with 1/z = 0.49 ± 0.09. The films showed a local roughness exponent αloc = 0.89 ± 0.01, global roughness exponent α = 1.72 ± 0.14 and spectral roughness exponent αs = 0.85 ± 0.03, suggesting that the growth of MoS2 thin films followed intrinsic anomalous scaling behavior (αs < 1, αloc = αs ≠ α). Shadowing owing to conical incoming particle flux distribution towards the substrate during deposition has been attributed to the anomalous growth mode. The optical properties of the films, extracted from ellipsometric analysis, were also correlated with RMS roughness and cluster size variation which unveiled the important role played by surface roughness and film density.

In this present work, detail experimental characteristics of SA333 Gr. 6 carbon steel have been critically examined under uniaxial strain-controlled ratcheting and post ratchet strain cycling. Asymmetric cyclic plastic deformation, i.e., drifting of mean strain cycle by cycle is termed as strain-controlled ratcheting. Increment of mean strain induces additional hardening under strain-controlled ratcheting. Mean strain induced additional hardening which is primarily kinematic in nature. Also, the material exhibits mean stress relaxation behavior under strain-controlled post ratchet strain cycling. After certain accumulation of mean strain severe cyclic softening is observed on stress amplitude under uniaxial multistep post ratchet strain cycling. Cyclic softening on stress amplitude is primarily because of ratcheting damage. The proposed model incorporates ratcheting induced additional hardening under strain-controlled ratcheting and exhibits mean stress relaxation characteristics under strain-controlled post ratchet strain cycling through an internal variable of memory stress parameter to account for the effect of prior loading history. The proposed model is implemented in user subroutine UMAT of Finite Element software ABAQUS. The proposed model is validated through close correlation between simulation and experiments.

In this work, a modified cyclic plasticity model for FEM analysis of SA333 C–Mn steel has been developed. A memory stress based isotropic formulation is integrated into the modified Ohno-Wang model to revamp its nonmasing and hardening/softening characteristics. Accurate estimation of stress–strain hysteresis loops is a prerequisite for performing fatigue life analysis. The inbuilt classical cyclic plasticity model available in commercial FE software cannot precisely describe the material behavior. The proposed model has been implemented by using user-defined material (UMAT) subroutine with FORTRAN code on the ABAQUS platform. To evaluate the material constants for the proposed model, a set of experiments has been carried out under uniaxial loading condition. The same material constants are used for predicting simulation response for other loading conditions. To verify the proposed model, the simulation results are compared with experimental results which reveal good agreement under uniaxial loading condition

Modern days are driven by advanced technology which put forward the challenges of invention related to advanced engineering materials and advanced manufacturing process in order to cope up with burning global demand for new item or alternative product in more complicated and competitive atmosphere. While choosing an engineering material or any manufacturing process, researcher has to consider not only utility, application, feasibility, effectiveness but also bio-compatibility with a rational chronological priority, based on their immediate as well as long-term impact and sustainability. The rigorous study and research is needed for development of an alternative manufacturing process or material or both for commercialization. ECAP is commonly employed for severe plastic deformation (SPD) techniques to form ultra-fine-grained (UFG) microstructure. Excellent past research work on rolled Al alloy Al7075 with ECAP confirmed high strength associated with maximum value of elongation at failure of 322% at 300 °C with rate of strain as 10−3 s−1. Mechanical properties with precipitation kinetics of Al7000 series alloy through ECAP have been already studied in the previous research. ECAP with Al7075 at different temperature in one of the researches is carried at recent past. The objective of present researcher is to find out the future scope of work among existing researches. The introduction of suitable back pressure which may improve the workability of the specimen by removing dead zones through filling outer corner needs to be studied. The future attempt may be made in finding the optimum process parameters or complex combination of all parameters for best mechanical properties and through achieving maximum strengthening effect.

Deformation band localization modes, uniform tensile strength, and uniform elongation of Ferrite-Martensite Dual-Phase (DP) steels are analyzed by finite element (FE) study. Treating the microstructure inhomogeneity as the sole cause of imperfection, failure initiation is predicted as the natural fallout of plastic instability caused by load drop because of localized plastic strain in the Representative Volume Element (RVE) during straining. Strain partitioning between two phases (ferrite matrix and martensite island) are investigated on RVEs, and it reveals that the increase of martensite yield stress decreases the plastic deformation and increases the stress state in martensite. Whereas, a decrease in martensite island volume fraction (Vm) results in the reduction of plastic deformation and stress state in the island. Studies are then carried out to investigate the effects of the ferrite-martensite flow properties and martensite volume fraction on the macroscopic tensile deformation behavior and band localization of DP steels. Micromechanical based FE simulation results emphasize that an increase in initial yield strength and volume fraction of martensite increases the ultimate tensile stress (UTS) with the decrease in uniform elongation. Similarly, as the hardening rate of ferrite increases, it increases the ultimate tensile stress (UTS) and uniform elongation. Additionally, deformation band localization modes alter from inclined to perpendicular to the loading axis with an increase in martensite volume fraction and initial yield strength of martensite. The knowledge of this work can be used to design DP steels with desired mechanical properties.

The scaling behavior, as well as growth mechanism of polycrystalline WS2 thin films grown on glass and Si substrates by pulsed laser deposition as a function of the deposition time, has been studied using height–height correlation function using the AFM images. X-ray diffraction measurement confirms the increase in crystallinity of the WS2 thin film on both the substrates. The WS2 films deposited onto Si substrate showed high rate of roughening or interface width (w) and a rapid increase in island size or correlation length (ξ) of WS2 nanoclusters in comparison to the films deposited onto glass substrate. The WS2 films grown on glass substrate evolved following the nonlinear stochastic deposition equation, however, WS2 films on Si substrate follow a linear growth model. The difference in surface smoothness, thermal conductivity and sticking coefficient of the two substrates causes different growth patterns of WS2 films onto the substrates. The growth of the WS2 films on the two different substrates evolved differently which has been realized more conveniently by schematically analyzing the behavior of the evolution of ξ and w with deposition time, t. The high roughness of the films deposited onto oxidized Si provides a large surface area, which will be useful for electro-catalysis applications.

The present work focuses on the effect of He pressure (vacuum, 10−2–5 mbar) on structural and optical properties of amorphous silicon carbide (a-SiC) thin films, deposited by pulsed laser deposition (PLD) technique onto fused silica. A stoichiometric change occurs in PLD a-SiC film, with increasing He deposition pressure, transforming a near stoichiometric SiC material to C-rich SiC films till 1 mbar of He pressure followed by drastic decrease in carbon (C) content at 5 mbar. The optical band gap of the films estimated using Tauc plot from UV–Vis–NIR transmittance spectra showed initial increase from 2.09 to 2.61 eV with increasing He pressure from 10−6 to 1 mbar, then decrease to 2.11 eV at 5 mbar. A broad band photoluminescence (PL) peak featured in each of the a-SiC films at room temperature. The PL spectra exhibited blue shift in peak energy from 1.8 to 2.2 eV with increase in atomic percentage of C from 49.4 to 62.4%. The origin of the PL exhibited in these films is clearly due to band tail emissions from amorphous SiC structures which has been explained by the observed variation of PL intensity and corresponding FWHM with band gap as well as Urbach energy.

The present report demonstrates the efficacy of Raman mapping over X-Ray diffraction (XRD) and spectroscopic ellipsometry (SE) in structural characterization of nanocrystalline Silicon (nc-Si) films having spatial heterogeneity in crystallinity and structure. The Si films were deposited via pulsed-laser deposition (PLD) technique at room temperature and elevated substrate temperature (Ts) of 400 °C and 700 °C, under vacuum (∼10−6 mbar). XRD showed that all films were polycrystalline while SE studies showed that only at 700 °C, the film was nanocrystalline in nature otherwise largely amorphous at lower Ts. This discrepancy in results is well explained by Raman maps which confirmed the presence of micron sized structures composed of nc-Si embedded in otherwise uniform matrix comprised of amorphous Silicon (a-Si) for films fabricated at room temperature and 400 °C whereas at 700 °C the uniform background matrix is dominated by nc-Si. The real and imaginary parts of pseudo dielectric function (e1,e2) versus energy spectra obtained for films grown at RT, 400 °C, and 700 °C were modeled and fitted to substrate/film/top SiO2 layered structure. The simulated (e1,e2) patterns are in excellent agreement with the recorded spectra. From the SE studies the band gap and thickness of the films were estimated. Band gap energy was found to vary from 1.35 to 1.30 eV approximately with increasing Ts from room temperature to 400 °C, then gradually increases to 1.55 eV at 700 °C. The variation of other optical constants of the films as a function of Ts also reflects the structural transition from amorphous-like to nanocrystalline-like with increasing Ts.

In the present paper, a systematic study on the structural, linear and nonlinear optical properties of Zn 1-x Ti x O (0 ≤ x ≤ 0.050) thin films is documented. The thin films are grown onto fused silica substrate via pulsed laser deposition technique employing 2nd harmonic of a Q-switched Nd:YAG laser (532 nm, 10ns, 10 Hz). The crystallinity of the film is observed to be increased initially up-to x = 0.02 and then decreased for higher values of x. A small variation in band gap energy is observed in the Zn 1-x Ti x O thin films with x which is mainly due to the Burstein Moss effect followed by the weak quantum confinement effect. The third order optical nonlinearities in the films are experimentally recorded using modified z-scan technique under cw He:Ne laser (λ = 632.8 nm) illumination. The nonlinear optical coefficients; β and n 2 , are observed to be in the range of 1.1–6.0 cm/W and (1.0–4.1) × 10 −4 cm 2 /W, respectively. The maximum value of β (6.0 cm/W) and n 2 (4.1 cm 2 /W) are observed in the Zn 1-x Ti x O film having x = 0.02. These studies suggest that an optimum concentration of Ti content in ZnO is required for the enhancement in nonlinear optical behavior.

Monotonic deformation behavior of ferrite-martensite dual phase steels with martensite volume of 13-43% have been analyzed in the current investigation using micromechanics based finite element simulation on representative volume elements. The effects of martensite volume fraction on the strain partitioning behavior between soft ferrite matrix and hard martensite islands in dual phase steels during tensile deformation have been investigated. As a consequence of strain incompatibility between hard martensite and soft ferrite phases, inhomogeneous deformation and finally deformation localization occur during tensile deformation. Restricted local deformation in ferrite phase caused by the adjacent martensite islands triggers the local stress triaxiality development. As the martensite volume fraction increases, the local deformation restrictions in ferrite phase also increases and which results in higher stress triaxiality development. Similarly the strain partitioning behavior between ferrite matrix and martensite island is also influenced by the volume fraction of martensite. The strain partitioning coefficient increases with increasing martensite volume fraction.