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Due to high densities of energy, power, and remarkable operational efficiency of Li-on battery when in contrast to Lead-acid batteries and nickel-cadmium batteries are examples of other types of batteries. Vehicles, electronics, aircraft, and other industries are all interested in lithium-ion batteries right now. However, some critical variables, such as performance degradation under extreme driving circumstances due to temperature difference in the lithium-ion cell, limit its usefulness. As a result, it's important to decide the optimal course of action based on the consequences of heat generation on various lithium-ion cell components. This paper looked at how heat is generated and how it affects each component of a li-ion battery. An analysis of different heat-controlling systems employing various design structures in numerous techniques of cooling such as liquid convection, phase transition material, air Convection and a combination of these techniques are used. Finally, utilizing a variety of design frameworks, a summary is created [ABSTRACT FROM AUTHOR]

The first, and at the same time one of the most important tasks in building a predictive system is the task of analyzing the original data set. The next task is to process the data according to the purpose and objectives of the predictive system. These two tasks are often not given enough attention and, as a consequence, the developer does not get the desired result as a result of building the system. This paper discusses methods and algorithms for data analysis and processing that can help in building a predictive system. The data set from the machine learning competition "ASHRAE - Great Energy Predictor III" is used as input data. The analysis phase focuses on constructing graphs and drawing conclusions from them. The paper shows how to use graphical information to find anomalies in the data and eliminate them. Examples of graphs that provide information useful for building machine learning models are given. The data processing phase describes the transformations performed on the data. It considers the transformations that lead to positive results as well as those that lead to negative results. [ABSTRACT FROM AUTHOR]

The fibre-reinforced composite structural members play an essential role in enhancing the strength-to-weight ratio of the structure. Smart reinforcing fibres like Shape Memory Alloy (SMA) provide an additional feature of adaptive stiffness to the structure. In this paper, SMA wire-reinforced epoxy resin composite is analyzed for change in natural frequency with respect to change in transformation temperature of SMA wires to reveal the difference in stiffness of composite beam, which is a function of change in transformation temperature from martensite to the austenite phase. The numerical study is carried out using FEA software, and the experimental validation of the same is completed. The natural frequency shift is predicted by measuring the natural frequencies of the composite for free-free boundary conditions at different transformation temperatures. The significant change in the natural frequency of composite is observed during the shift in transformation temperature, and the FEA results are close to experimental results with reasonable accuracy; thus, the proposed composite provides adaptive stiffness. [ABSTRACT FROM AUTHOR]

The present paper analyzes failure observed in polymer rods collided with a steel anvil under the Taylor cylinder impact experiments. The experimental and numerical analysis demonstrates that association of the failure patterns with the loading mode depends on the rod material. Two materials are considered in the paper, specifically, polymethylmethacrylate (PMMA) and polycarbonate (PC). Damage in PMMA rods at the Taylor tests is shown to be dominated by the shear load resulting in plastic deformation. In contrast, the major mechanism of damage in PC rods is governed by omni-directional (pressure) mode of load. Analysis of the damage in sections of the rods associated with the glass transition is also addressed in the present theoretical study. Failure in these polymers follows the traditional fracture wave mechanism for brittle glass-type materials due to load in the corresponding mode. Numerical analysis employs a two-phase model with improved inter-phase thermal balance accounting for the inter-phase mass, momentum, and heat exchanges during the glass phase transition, while damage being accumulated in time. The simulation results demonstrate a good correlation with the experimental results. [ABSTRACT FROM AUTHOR]

The crystalline sample of PbNb2O6 (Lead meta niobate or PN) was grown by solid-state reaction method. The material crystallizes in an orthorhombic structure at room temperature and its phase transition temperature was confirmed by hysteresis loop studies reported in our previous paper. The dielectric relaxation properties are investigated here for this material, in a temperature range from 27°C to 600°C in the frequency range (10 – 106 Hz). A supportive study of micro-structural features of the sample has been reported to confirm the mechanism of dielectric relaxation processes and relaxation kinetics. It is concluded that the dielectric relaxations occurring at low frequency are related to the presence of space charges in association with vacancies, which are trapped at the grain boundaries. [ABSTRACT FROM AUTHOR]

The lap joint of Zincalume G550 steel is welded by Metal Inert Gas (MIG) welding and ER70S-6 filler wire. 16.5 – 17.5 v of welding voltage and 3 – 4.5 m/min of wire-speed are set in parameters under the 70 A of constant welding current. The welded specimens were cold-mounted and cut with a cutting machine and the cross-section of the joints was ground with three different abrasive papers (220,1000,2000) and etching with Ferric Chloride (FeCl3). The microstructure of the joint surface is investigated. The fine (at FZ) and coarse grains (at HAZ) are identified clearly. In experimental testing, it can be seen that high welding voltage and low wire speed produced high heat energy, which can be led to the creation high volume of perlite structure in the weld zone and the grain size of the HAZ (heat affected zone) was much bigger than FZ (fusion zone) during the MIG process. The welding voltage is a direct relationship with forming microstructure that the phase transformation increases when the welding voltage increases. However, low wire speed can be expanded the size of the weld region where the fine grains are observed. In the FZ, the perlite structure (a-Ferrite and cementite) moved between the FZ and the HAZ, and the cementite grain much formed under the high-temperature end of the FZ. [ABSTRACT FROM AUTHOR]

Piezoelectric ceramics possess polarization under stress and ferroelectric is a subcategory of piezoelectric which possess spontaneous polarization, phase transition, permittivity, electrical and optical characteristics beneficial for energy storage devices, capacitors, memories, sensors, generators and numerous other applications. Perovskite is the most important and appreciable class of ferroelectrics having structure 퐴퐵푂3. Here we described the structure, formation and application of some perovskites [e.g퐵푎푇푖푂3(BTO), 퐵푎(푆푟푥푇푖1−푥)푂3(BST), 푆푟푇푖푂3(STO), 푃푏푇푖푂3(PT), 푃푏(푍푟푥푇푖1−푥)푂3 (PZT)] which exhibits piezo, pyro and ferro-electricity. In this paper we will discuss the use of these perovskite structure in the fabrication of thin and thick film form by sol-gel synthesis, spin coating, chemical solution decomposition, sintering and milling utilized in detection of gas, light,humidity, temperature and pressure sensor-based application in detail. [ABSTRACT FROM AUTHOR]

Rural settlement is an integral part of human shelter, which is generally organized in an organic form, in which groups of people cluster in a community, whose large proportion of the human population survives on agriculture and related professions. With the course of fast pace development, the villages are engulfed by towns and cities. Their agricultural lands are either acquired for a handsome ransom or occupied by builders by paying a huge sum of capital to the landlords. Here comes the transition phase, where traditional living styles take place in an urban environment that neither remains rural any more, nor adopts completely urban living styles. As a result, these peri-urban villages, not only lose their identity, but also fail to generate employability. So villagers migrate to metropolitan cities. This is the need of the hour to work on the rural renaissance, economic, cultural, well-being, and social sustainability on a priority basis, in selected prototype. This paper addresses the research gap that can be bridged with a multidisciplinary approach, in which the experts from all necessary disciplines shall coordinate on one platform and work on the overall well-being with smart usage of digital methods that suggest smart solutions to achieve sustainable village life and lifestyle, as well as restore its past glorious identity to secure a place in the smart village mission. [ABSTRACT FROM AUTHOR]

The paper considers laboratory experiments on unilateral freezing of samples of dry and wet sand. Freezing was carried out in the refrigerator under the influence of a cooling thermal plate from above. Thermometry of frozen sand samples was performed. As a result, the propagation velocity of the cold wave in the samples, the movement of the freezing front and the duration of the phase transition are estimated. Mathematical modeling of the sample cooling process was also performed. [ABSTRACT FROM AUTHOR]

Actuation is essential for the development of micro/nano electro-mechanical systems and the use of shape memory materials can be a solution for such a need. These materials exhibit structural phase transformation which is associated with changes in the thermo/magnetic/mechanical properties that can be used to control the actuation in various architectures. The magnetron sputtering deposition of films from such materials allows the generation of simple and complex architectures that can be used for micro and nanoactuation. This paper details several solutions to generate micro/nano actuation in bimorph and more complex architectures, and the way to control the actuation profile as a function of the phase transformation degree in the film. [ABSTRACT FROM AUTHOR]

Material extrusion-based additive manufacturing, strictly speaking of the Fused Filament Fabrication (FFF), is characterized by using a thermoplastic polymer in form of a solid filament as a built material. The filament partially melts inside of a heated hotend and is subsequently extruded under the pressure generated by the filament feeding force of the feeding rollers. The processes in the heated extrusion channel are complex and difficult to model, as the melt properties are a nonlinear function of temperature and shear rate. Moreover, there is a phase transition from solid filament to liquid melt. In this paper, the required feeding force and resulting extrudate temperature at the nozzle outlet at different feeding rates, liquefier temperatures and nozzle geometries of two acrylonitrile-butadiene styrene (ABS) and polypropylene (PP) materials were investigated. For a better understanding of the melting process in the hotend, the degree of melting of the strands was determined via dead-stop experiments at selected operating points. Two process windows could be identified: At low feeding rates, the feeding force increases linearly with increasing velocity, and at a certain point, the force increases rapidly and fluctuates. The melting investigations showed that this is related to the increasingly unmolten material reaching the nozzle outlet. The semi-crystalline PP showed a smaller processing window for stable flow compared to ABS and lower extrudate temperatures due to its differentiated cp progression at the phase transition. Based on the experimental studies, Computational Fluid Dynamics (CFD) simulations were performed to predict the pressure and temperature distributions inside the channel. For modelling the shear-dependent viscosity the Carreau model was used, while the temperature dependency was described by a jump function with a solid viscosity of 106 Pa.s. It is shown that the numerical model can predict the feeding force with good accuracy and represent the change between process windows at increasing speeds. [ABSTRACT FROM AUTHOR]

Shape memory alloys (SMAs) are materials that both industry and research are interested in. SMAs are materials that, after a seemingly irreversible deformation, can return to their original shape. This alloy has poor yield strength when heated below its transformation temperature and will simply deform into any new shape that it can retain. SMA changes its crystal structure and returns to its original shape when heated above its transformation temperature. Because of their superior properties such as shape memory effect (SME) and pseudoelasticity, which are related to the specific way the biocompatibility, phase transformation temperatures, corrosion resistance, high wear resistance, and high strength, SMAs can be utilized in a variety of applications. This paper focuses on the features of SMAs, such as shape memory effect and superelasticity, as well as their types, fabrication processes, and the most significant applications. [ABSTRACT FROM AUTHOR]

In the present paper we consider a phase transition in a viscous liquid in a solid skeleton near a single pipe filled with hot water. We suppose that the tube itself is part of a solid skeleton. First, we consider this physical process at the microscopic level (the characteristic pore size ε' is approximately 5-20 microns) governed by Stokes equations for incompressible viscous liquid coupled with heat equations. We also assume that the liquid in the frozen state becomes the part of the unmoved solid skeleton. Note that the boundary between the solid and liquid parts of the pore fluid is unknown (free boundary) and must be found together with the solution to the Stokes equations. The suggested mathematical model at the microscopic level is physically correct, because based on the classical Newtonian continuum mechanics. But any physically correct mathematical model at the microscopic level is practically useless due to its average size. Indeed, for the numerical implementation of any such model, a step in spatial variables of several microns is required. On the other hand-side, the problem must be calculated for domains of several tens meters. No modern supercomputers or cluster computing systems are yet capable of such computations. To make it practically valuable, we must use homogenization method, which is, roughly speaking, the mathematically rigorous approximation of the microscopic mathematical model in consideration by some macroscopic mathematical model. This part will be done in the next publication. [ABSTRACT FROM AUTHOR]

The paper considers the change in the volumetric gas content, the formation of hydrate and the dynamics of pressure waves during its propagation in a channel with a variable cross-section containing water and a hydrate-forming gas Freon-12, and also considered the case of variable volumetric gas content in the channel during this process. Initially bubbly liquid is under pressure P0. Further, the pressure in the system suddenly rises to the value of Pe, after which a pressure wave of a stepped profile propagates through it to the creation conditions for the hydrate formation during its propagation in a narrowing channel was shown, without taking into account the processes of fragmentation of gas bubbles and the presence of surfactants. Also shown is the change in the amplitude of the pressure wave due to the formation of gas hydrate. In addition to changing the geometry of the channel, the paper also considers the case with a change in the volumetric gas content, due to the fact that the liquid increases its acoustic elasticity. The intensity of the gas phase transition in the work is described on the basis of the theory of nonequilibrium phase transitions in vapor-liquid systems. [ABSTRACT FROM AUTHOR]

This paper presents an overview of bainite transformation in low carbon steel, which is alloyed with some alloying elements such as Mn, Si, Cr. The article also presents an overview of the transformation mechanism of this steel group. From the synthesis of research works, the influence of alloying elements on steel's microstructure and mechanical properties has been determined. And the final article, the bainite microstructure of CMnSi steel was found when deforming and heat treatment. By OM, the bainite structure was found. The article presents the influence of the deformation process on the microstructure and mechanical properties of low carbon alloy steel, which heat treatment by TBF processing. The samples are deformed at different levels: 20%, 40%, and 80%. The research results show that: When the sample was deformed with 80%, the highest strength was 800MPa, the highest elongation was 36%, the product between the strength and the elongation (Rm*A) was the highest: 28774MPa*%. This alloy deformed at a level of 80%. The content of austenite in this alloy's microstructure was the highest, about 16%; the content of ferrite was 52%, with the average particle size of ferrite being 6.4 µm; the particle of residual austenite was 2 µm. The microstructure results have contributed to improving the mechanical properties of steel. The phase that improved the mechanical properties of this alloy had grain size and dispersed. [ABSTRACT FROM AUTHOR]

Many metals and alloys have a complex of mechanical properties that ensure their wide application in engineering, in particular as structural materials. This is, first of all, a combination of high plasticity with significant strength and resistance to deformation, and the ratio of these properties can be regulated in a large range using mechanical and thermal treatments of metals, as well as the production of alloys of various compositions. The structural metal materials and alloys used in engineering are polycrystalline. Their mechanical properties are practically isotropic and may differ significantly from the properties of single crystals. In this paper, the crystal structures, strength and plastic properties of iron-manganese-based alloys, as well as alloys alloyed with silicon, are determined. All experiments were carried out on the X-ray installation "dRone", at the Central Research Institute of Ferrous Metallurgy named after I.P. Bardin. Dilatometric studies to determine the temperatures of direct and reverse martensitic transformations, the Neel temperature - the temperature of the magnetic phase transition were carried out on the quartz direct dilatometer "Sinco-Rico" and the German dilatometer "Linsay". [ABSTRACT FROM AUTHOR]

There is an extensive literature on atomistic modeling of the structure and properties of binary alloys, but for multicom-ponent alloys, despite their widespread use, much less work has been done. The widely used molecular dynamics method analyzes time intervals of the order of a nanosecond and therefore it is not applicable to the analysis of such slow processes as diffusion and does not allow one to model order-disorder phase transitions. Such a possibility is provided by the Monte Carlo method, which simulates diffusion by the vacancy mechanism. This paper presents a theoretical model that allows one to study diffusion processes in ternary alloys based on an fcc lattice assuming the model of hard coordination spheres. The influence of the third component on the structure and energy of the alloy is shown. [ABSTRACT FROM AUTHOR]

The paper presents the study of the process of deformation-induced γ → α-transformation in TRIP-steel and its effect on the strain-hardening coefficient at the macroscopic level. It is shown that a phase transformation starts with the propagation of Luders bands during the pseudo-plateau, when the strain-hardening coefficient is constant. The boundaries of Luders bands are switching autowaves of localized plasticity. After the annihilation of switching autowaves in the samples in the austenitized state, the phase transformation continues with the movement of deformation fronts of the Portevin–Le Chatelier bands, which are excitation autowaves. In this case, the strain-hardening coefficient increases to a maximum value and then decreases up to fracture. The nucleation and propagation of phase transformation fronts is confirmed by magnetic measurements. After the transition to the stage where the hardening coefficient decreases, the γ → α' phase transformation decays and is no longer the predominant mechanism of plastic flow. [ABSTRACT FROM AUTHOR]

In the paper using the molecular dynamics method, several combinations of interatomic potentials are analyzed to describe the interaction of elements of a multicomponent Al-Cu-Ni alloy. The possibility of describing martensitic transformations proceeding under conditions of thermomechanical action was investigated. The studies made it possible to construct a physically correct model of the Al-Cu-Ni alloy and to analyze some regularities of structural transformations occurring in it under mechanical action and heating. The constructed model can be used for further research using a numerical experiment. [ABSTRACT FROM AUTHOR]

In this paper, we develop the theory of nucleation and evolution of crystals during the intermediate stage of phase transformation processes in metastable melts and solutions with allowance for the Gibbs-Thomson and attachment kinetics effects. An exact analytical solution of non-linear model equations is found in a parametric form. It is shown that the distribution function represents a bell-shaped curve moving with time, and the liquid metastability reduces with time as a result of the evolution of a polydisperse ensemble of crystals in a supercooled (supersaturated) system. [ABSTRACT FROM AUTHOR]

The most prominent failure in electronic devices is due to excessive heating of the device during its operation. And the modern trend of miniaturization of electronic devices with better performance and features further extends the need for a proper cooling system. The phase change material (PCM) cooling technique is one of the most economical passive cooling methods which avoids mechanical vibration of the cooling system and provides stable cooling with repeated uses. This review paper presents the thermo-physical properties of commonly used PCMs and different types of thermal conductivity enhancers (TCE) for electronic devices. The findings of this literature consisting of both experimental and numerical works can be used as a guideline for future researches in this field. Heat transfer enhancement in PCM can be achieve using fins, porous media, mixing with carbon additives, microencapsulation of PCM, and by adding nanoparticles. For heat sink with fins, the volume fraction of the PCM and TCE is found to be directly affecting the performance of the cooling system. Also, distributed pin fins, the pattern of arrangement, shape, and size of the fin affects the heat transfer to the PCM. Microencapsulation also increases the heat transfer surface area of PCM. However, the selection of shell material and the core material is important to obtain the targeted thermal properties. Also, metal and metal oxide nanoparticles can significantly increase the heat conduction and diffusion capacity of the PCM. But, each of these enhancement methods has certain demerits which constantly required to be addressed to achieve a more efficient cooling system for modern electronics. [ABSTRACT FROM AUTHOR]

Aluminum-steel clad composites are used as structural elements in car bodies and chases as well as in the chemical industry due to a combination of high strength of steel, low density of Al and high corrosion resistance of both materials. An important parameter influencing mechanical properties of the composite is the microstructure of the bonding region between Al and steel layer. During manufacturing of the final product, clad sheets can be subjected to elevated temperatures which enhance diffusion between the metals. As a result, a brittle intermetallic phase, deteriorating the bond strength between steel and aluminum, forms at the interface. This paper focuses on study of the interfacial microstructure in a twin-roll cast Al-steel clad strip and its evolution during in-situ annealing in transmission electron microscope. Due to isochronal annealing above 500 °C, Al5Fe2 phase forms at the interface. Nucleation centers formed at the beginning of heating experiment expand and form continuous layer. The kinetics of the growth follows the parabolic law typical for diffusion-controlled phase transformations. [ABSTRACT FROM AUTHOR]

We had introduced a microscopic technique to obtain heat capacity peaks near first-order phase transitions in polycrystalline phase change materials (PCMs). Such PCMs are composed of a large number of segments or grains, so that the total heat capacity of a PCM is a double average of heat capacities in the individual grains. One average is over surface (or boundary) effects occurring due to interactions of grains with their surroundings, while the other average is over grain sizes. Using this approach, we were able to derive a formula for heat capacity peaks and use it to very accurately fit experimental data for three selected PCMs measured by adiabatic scanning calorimetry. The fitted values of the phase change temperature for these three PCMs were not convincing, however. In this paper we argue that the reason for this controversy stems from too a crude approximation of surface effects that was used originally. Therefore, here we propose an improvement of our technique by suggesting a more appropriate approximation that still leads to as accurate fits as the original one. We illustrate this for one of the three PCMs. [ABSTRACT FROM AUTHOR]