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This study aims to predict the various phases present in high entropy alloys (HEAs) and consequently classify their crystal structure employing multiple machine learning (ML) algorithms utilizing five thermodynamic, electronic and configurational parameters which are considered to be essential for the formation of HEA phases. The properties of a high entropy alloy can eventually be traced through accurate phase and crystal structure prediction, which is essential for selecting the ideal elements for designs. Twelve distinct ML algorithms were executed to predict the phases of HEAs, adopting an experimental database of 322 different HEAs, involving 33 amorphous (AM), 31 intermetallics (IM), and 258 solid solutions (SS) phases. Among the twelve ML models, Cat Boost Classifier displayed the optimum accuracy of 98.06 % for phase predictions. Further, crystal structure classification of the SS phase (body-centered cubic- BCC, face-centered cubic- FCC, and mixed body-centered and face-centered cubic- BCC+FCC) has endeavoured for better microstructure evolution using a different database containing of 194 additional HEAs data with 61 FCC, 76 BCC, and 57 BCC+FCC crystal structures and in comparison to the other models tested, the Gradient Boosting Classifier evolved with the highest accuracy of 86.90 %. An ensemble classifier was also introduced to improve the performance of the ML models, resulting in an accuracy increase to 98.70 % and 86.95 % for phase and crystal structure predictions, respectively. Additionally, the influence of parameters on model accuracy was determined independently.

A river tries to maintain a dynamic equilibrium state by adjusting different controlling factors. A significant change in one of the controlling factors will dictate modifications in the others to re-establish the equilibrium in a river system. A river basin may indicate active tectonic movements more precisely than the best space-based geodetic techniques. Morphometric analyses, with the help of DEM and GIS often generates insights into the tectonic activities of an area. The Dhansiri (North) River basin lies on the north bank of the Brahmaputra and on the northern part of the Dhansiri-Kopili fault, which is tectonically active at different times. This paper analyses the impact of relative tectonics on drainage pattern development in the basin based on various morphometric parameters of linear (stream length ratio, bifurcation ratio), areal (form factor, basin elongation ratio), and relief (relief ratio, ruggedness number) aspects. Eleven well-known ML algorithms,namely, Logistic Regression (LR), K Nearest Neighbors (KNN), Random Forest (RF), Support Vector Machine (SVM), Decision Tree (DT), Gaussian Naive Bayes (GNB) classifier, Neural Network (NN), Extra Tree Classifier (ET), Ada Boost Classifier (AB), Gradient Boosting Classifier (GB), XG Boost Classifier (XGB) is used to model the spatial distribution of relative tectonic activity.These algorithms were executed in Python to assess prediction accuracy using standard metrics like accuracy, precision, recall, and F1 score. The assessment utilized widely used libraries such as sci-kit-learn and TensorFlow to implement and test the algorithms, benefiting from their comprehensive model evaluation and performance assessment tools. The SVM, ET, DT, and GNB techniques had the best performance, achieving an accuracy of 82.60 percent as per the modeling results.The Dhansiri (North) is a sixth-seven-ordered basin characterized by a dendritic drainage pattern. Notably,the spatial prediction of morphometric parameters with ML is potentially competent for regional analyses of neotectonics.

The “heat checking” phenomenon, which occurs due to thermal fatigue, is one of the dominant mechanisms in shortening the lifetime of dies which undergo sequential in-service high- and low-temperature operating cycles. This phenomenon results in the formation of a network of microcracks on the surface, which deepens with further repetition of thermal cycles. The service lifetime of dies made of hot work tool steel is characterized by successive changes from high to low temperatures. Hot deformation processes are subjected to working temperatures above 300 °C. In order to increase the die lifetime, many studies have been conducted to understand the mechanism of crack formation and find ways of prevention. However, there is no comprehensive study on the effect of the die production process, e.g., from the steelmaking to the die manufacturing step. In addition, it is important to understand the effect of service conditions on “heat checking” occurrence. In the present research, a short overview of this phenomenon has been provided including the definition, formation mechanisms and characteristics of “heat checking”. In addition, the influence of the steel characteristics such as surface engineering, heat treatment and service conditions on the phenomenon is investigated. As the simulation and theoretical aspects of “heat checking” are extensively investigated and summarized and the lack of knowledge is mostly in experimental parts, in order to fill the existing gap, this overview is preferentially focused on and summarizes experimental literature outputs rather than theoretical ones.

Countless research has suggested Yttria-stabilized Zirconia (YSZ) to be a top candidate for being implemented as thermal barrier coatings (TBC). However, when exposed to prolonged service, temperature and stress variations succeed in initiating a catastrophic phase transformation from tetragonal to monoclinic structure in Zirconia. Hence, the estimation of endurance for YSZ-based TBC is necessary to minimize failure in such situations. The main purpose of this research was to determine the relationship between tribological investigations and the estimated lifespan of YSZ coatings accurately. The study used various methods such as wear resistance testing, optical profilometry, specific wear rate, and coefficient of friction to estimate the maximum durability of TBCs. The research also provided insights into the composition and microstructure of the TBC system and found the optimized concentration of Yttrium doping to be 3.5 wt %. The study discovered that erosion was the main cause of roughness depreciation from SN to S1000. The estimation of the service life was primarily made based on optical profilometry, specific wear rate (SWR), coefficient of friction (COF) and wear resistance values which were further supported by the results of chemical characterization of the samples through electron dispersive spectroscopy (EDS), wavelength dispersive spectroscopy (WDS) and X-Ray Diffraction (XRD) analysis. The results were reliable and accurate and suggested future areas of investigation, such as 3D profilometry for surface roughness and thermal conductivity evaluation using laser-assisted infrared thermometers.

In this paper, the hot deformation behavior of Zn–22Al alloy was investigated by performing hot compression tests under different deformation conditions. The Arrhenius-type constitutive model was developed and the constants were determined for this alloy. In addition, the processing map was constructed using the principle of the dynamic materials model (DMM). The results show that the Arrhenius-type model, with an activation energy of 63.722 kJ/mol, can provide an accurate prediction of the flow behavior of the alloy at various conditions. The higher energy dissipation efficiency was observed in the high-temperature ranges and low strain rates. The results showed that the unstable processing zone of Zn–22Al alloy has mainly occurred at high strain rates and low-temperature region. Besides, it is found that the strain has less significant effects on instability parameter and power dissipation efficiency.

In this research, the effects of annealing temperature (500, 550, and 600 °C) on the microstructure and mechanical properties of a conventionally (1 cycle) and severely (6 cycles) deformed Fe–24Ni martensitic steel, processed by accumulative roll bonding (ARB), were investigated. Electron backscattered diffraction (EBSD) analysis revealed that annealing at 500 and 550 °C for 30 min was insufficient for completing the reverse martensite transformation, and consequently, the microstructure consisted of austenite and martensite. However, complete reverse martensitic transformation has been accomplished after annealing at 600 °C for 30 min for both deformed samples. Both yield strength (YS) and ultimate tensile strength (UTS) were increased after first and sixth cycle of rolling. Subsequent, annealing led to a decrease in YS and UTS with improvement in uniform elongation (eu). In addition, the work hardenability was also improved by annealing the deformed samples.

The wear debris from conventional brake pads is a growing source of environmental contamination that often leads to life-threatening diseases for human beings. Though the emerging organic brake pads show potential to serve as an eco-friendly alternative, their mechanical and tribological properties are not adequate to withstand the demands of high-wear resistance of a functioning braking system under regular use. Metal matrix composites have served as an optimal solution with minimal environmental pollution and appreciable physical properties. Owing to the popularity of aluminium metal matrix composites, the present study is based on the fabrication and characterization of SiC-reinforced LM6 alloy through stir casting methodologies for evaluating its worthiness in application as a brake pad material. Microstructural, compositional, and phase characterizations were executed through optical micrography, X-ray diffraction, and energy-dispersive X-ray spectroscopy analysis. Although mechanical properties were evaluated through surface hardness investigation, parallel thermal properties were estimated through thermal conductivity evaluation. Finally, the execution of tribological analysis and precise microstructural observations of wear track at ambient and elevated temperatures helped in establishing the datum that the fabricated metal matrix composite (MMC) is a reliable brake pad material alternative.

Monte Carlo (MC) simulation was used to predict the microstructural evolution and the kinetics of grain growth during heating of Zn–22Al dual phase alloy. As the prediction of MC simulation is based on virtual simulation time, time conversion plays a significant role in determining the recrystallization and growth kinetics of the alloy. The problem is more critical for the alloys in consideration that, they are composed of two phases with different grain boundary motilities. In this article, effort has been made to develop and modify the Monte Carlo algorithm of normal grain growth for simulating Ostwald ripening and grain growth in two-phase Zn–22Al alloy system. Grain-boundary migration (GBM) and the experimental data-based (EDB) models predict accurate relationship between simulation and real time among proposed relationship. It has been found that the grain growth of Zn–22Al is controlled by diffusion along grain boundaries (n = 4) and a reasonable agreement between the simulation and experimental results has been attained.

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.

Optical microscope (OM), field emission scanning electron microscope (FESEM), energy dispersive X-ray Spectroscopy (EDS), transmission electron microscope (TEM) differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were employed to investigate the evolution of intermetallic phases during homogenisation at 465 °C for 0–48 h for Al-Zn-Mg-Cu-Sn alloy. Evidentially, casting is accompanied by severe dendritic segregation. The primary phases appeared during casting consisted of α (Al), eutectic mixture of η (Mg (Zn, Cu, Al)2), θ (Al2Cu) and coarse Al7Cu2Fe particles. After 6 h of homogenisation, two eutectic phases namely S (Al2CuMg) and Cu3Sn were formed. The appearance of dendrites and their consequent dissolution with the progress of homogenisation time was modelled using a kinetic equation taking interdendritic spacing and temperature as two variants. TEM micrographs revealed the presence of high density of fine dispersoids after 6 h of homogenisation following almost complete dissolution of the dendrites into the matrix after 48 h of homogenisation. Coarsening of the said dispersoids was observed with further homogenisation treatment following Ostwald ripening mechanism and consequently lowering of Zener pinning pressure (ZPP). Crystallographic texture analysis revealed the formation of strong γ fibre in both cast and homogenised samples. However, strong α fibre along with Goss, Brass, P, and Copper components was also noticed in the cast sample. Keywords: Homogenisation, Intermetallic phases, Dispersoids, Zener pinning pressure, Crystallographic texture

This paper represents the fabrication and characterization (microstructural, mechanical, and electrical) of Cu-2wt% B-4 wt% Ti and Cu-5wt% B-10wt% Ti alloy from the ball-milled Cu, Ti, and B powders. The in situ formation of TiB2 was also discussed in the light of differential scanning calorimetry (DSC) and X-ray diffraction (XRD). This present work investigates the effect of various parameters on powder production and the formation of in situ TiB2 through the thermo-mechanical route. The apparent activation energy during metastable phase formation for the two types of alloy composites has been calculated using the Johnson-Mehl-Avramani (JMA) equation and found to be 567.46 and 626.37 (KJ/mol), respectively. However, the findings of this study indicate the mechanical properties of the composite are due to the in situ formation of TiB2 particles in the Cu matrix. The properties of the composites after heat treatment were discussed employing mechanical and electrical properties and measured ultimate tensile strength (UTS) (~375 MPa), yield strength (~300 MPa), and hardness (~150 Hv) for a higher percentage of Ti and B addition. The electrical conductivity also decreased to 53% IACS as Ti negatively impacts conductivity.

Evolution of different phases formed on interstitial free (IF) steel after hot dipping in Al–Si–Mg alloy melt at 700 ​°C for 0.5, 1, 3 and 6 ​min were examined in the present research. Notable findings from XRD studies include presence of Al3FeSi2 (τ4) Al2FeSi (τ3) phases along with elemental Si and Mg in the form of Mg2Si. Composition profiles revealed by EDS and GDOES studies has been in line with the XRD results. Interestingly, EPMA study established presence of Si as isolated islands across the coating and up to the intermetallic layer apart from its association with Mg in the form of Mg2Si. The microstructure across the cross-section revealed by the EBSD technique showed three distinct layers consisting of Al–Si top coat, θ-FeAl3 and a major η-Fe2Al5 phase layer adjoining the steel substrate. This study also revealed ternary Fe–Al–Si intermetallic Al3FeSi2 (τ4) and Al2FeSi (τ3) phases scattered in the intermetallic layer. Texture measurement from EBSD revealed the presence of strong γ-fiber for 3 ​min hot dipped aluminized samples. Grain boundary characteristics distribution (GBCD) results indicated that the volume fractions of high angle grain boundaries were gradually increased with the advancement of dipping time.

Abstract Polysaccharides are structurally complex and essential constituents of life, and therefore, studies directed to these kinds of molecules have received scientific attention. Despite an easy availability of Dolichos biflorus Linn and Trachyspermum ammi (Linn) seeds isolation, characterization and antimicrobial studies of polysaccharides derived from these two natural sources have not been investigated. Therefore, we report here isolation of polysaccharides, their purification and characterization from Dolichos biflorus Linn and Trachyspermum ammi (Linn) seeds. Gel permeation chromatography, GC–MS, SEM, XRD, EDX and FT-IR analyses show the presence of three pentose sugar such as d-ribose, d-arabinose, d-xylose and hexose sugar such as d-mannose, d-galactose and d-glucose. Unprecedented antimicrobial activity of these polysaccharides against Gram positive bacteria such as Staphylococcus aureus and Bacillus subtilis and Gram negative bacteria such as Escherichia coli and Pseudomonas aeruginosa are established.

In recent years, synthesis of TiC reinforced Cu matrix composites are comprehensively utilized for industrial applications. Synthesis of Cu-TiC as a thin film can also be an intriguing challenge for such applications. In this work, Cu-TiC thin film was deposited by DC magnetron co-sputtering method and examined to investigate the role of C content on the micro-structure, electrical conductivity and surface morphology by using XRD, UV–vis spectroscopy, I-V characteristics, AFM, SEM and EDX analysis. The wt% of C was varied from 14 to 67% while depositing the Cu-TiC films. All the films have resulted to be polycrystalline with Cu and TiC phases. The optical band-gap has decreased from 2.59 to 1.93 eV and the refractive index got enhanced from 2.92 to 3.38 with increase in wt% of C. The ideality factor, electrical resistance, surface roughness across the films has also decreased as wt% of C was increased in Cu-TiC films.

The aim of this investigation was to assess the corrosion behavior of gray cast iron (GCI) alloyed with copper. Alloyed GCI specimens were austempered isothermally at varying temperatures. After austenitizing at 927 °C, the samples were austempered at different temperatures ranging from 260 to 385 °C with an interval of 25 °C for 60 minutes. As a result, these samples developed an ausferrite matrix with different percentages of austenite. The resulting microstructures were evaluated and characterized by optical microscope (OM), scanning electron microscope (SEM), and X-ray diffraction (XRD). The corrosion characteristics were determined using potentiodynamic polarization tests and electrochemical impedance spectroscopy (EIS) of these samples. These tests were carried out in a medium of 0.5 M H2SO4 and 3.5% NaCl solution. It was observed from the potentiodynamic polarization results that with increasing austempering temperature, the corrosion rate decreased. All results of the EIS were in accordance with a constant phase element (CPE) model. It was found that with an increase in austempering temperature, the polarization resistance (Rp) increased. The austenite content was also found to influence the corrosion behavior of the austempered gray cast iron (AGCI).