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This study investigated the impact of temperature, time, and homogenisation on the transient liquid phase bonding of Inconel 617 to stainless steel 310, employing AWS BNI2 foil as an interlayer. Nine test series were conducted at temperatures of 1050 °C and 1100 °C, with bonding durations ranging from 10 to 60 min. The homogenisation process was carried out on specimens that underwent full isothermal solidification at a temperature of 1170 °C for 180 min. The microscopic analysis indicated that extending the time and raising the bonding temperature resulted in the extension of the isothermal solidified zone, accompanied by a reduction in the quantity of eutectic phases. Complete isothermal solidification was seen exclusively in samples bonded at temperatures of 1050 °C for 60 min and 1100 °C for a duration of 50 min. The size of the diffusion-affected zone expanded as the bonding temperature and duration rose, but the presence of brittle intermetallic phases diminished. The microstructure of the homogenised sample indicated that the diffusion-affected zone had been almost completely eliminated. Hardness variations indicated heightened hardness in the diffusion-affected zone (DAZ) and athermal solidified zone (ASZ). Shear strength is maximised in homogenised specimens with minimised ASZ.

This study investigated the impact of temperature, time, and homogenisation on the transient liquid phase bonding of Inconel 617 to stainless steel 310, employing AWS BNI2 foil as an interlayer. Nine test series were conducted at temperatures of 1050 °C and 1100 °C, with bonding durations ranging from 10 to 60 min. The homogenisation process was carried out on specimens that underwent full isothermal solidification at a temperature of 1170 °C for 180 min. The microscopic analysis indicated that extending the time and raising the bonding temperature resulted in the extension of the isothermal solidified zone, accompanied by a reduction in the quantity of eutectic phases. Complete isothermal solidification was seen exclusively in samples bonded at temperatures of 1050 °C for 60 min and 1100 °C for a duration of 50 min. The size of the diffusion-affected zone expanded as the bonding temperature and duration rose, but the presence of brittle intermetallic phases diminished. The microstructure of the homogenised sample indicated that the diffusion-affected zone had been almost completely eliminated. Hardness variations indicated heightened hardness in the diffusion-affected zone (DAZ) and athermal solidified zone (ASZ). Shear strength is maximised in homogenised specimens with minimised ASZ. [ABSTRACT FROM AUTHOR]

In this study, standard stainless steel 310, modified 310 with Al and Ti and aluminised 310 were tested in supercritical water (SCW) at 500°C for 1555 h. Weight change measurement and microstructure analysis were carried out to evaluate the corrosion behaviour of these alloys and surface oxide formation in SCW. After 1555 h of SCW exposure, all modified and aluminised samples showed higher weight gain than 310, although weight loss commenced after 887 h for the aluminised samples. Al addition contributed to more surface spinel formation while Ti reduced spinel on the surface and helped form more uniform and dense surface oxide structure. In addition to higher weight gain and subsequent weight loss, aluminised samples also suffered from surface cracking, suggesting that high Al and low Cr surface content is not beneficial for SCW application. [ABSTRACT FROM AUTHOR]

Extensive precipitation can occur in high temperature materials during service. This is known to significantly affect the mechanical properties. To be able to study this phenomenon, particle formation in the austenitic stainless steel 310 has been quantified. In particular, σ-phase and M23C6-carbides have been analysed. Specimens have been aged up to 5000 h at 800°C. The precipitation of the two phases has been modelled. The basis of the model is diffusion-controlled growth. σ-phase shows a spherical growth and an M23C6 planar growth. The soft impingement of the diffusion zones with respect to both chromium and carbon is taken into account. The influence on mechanical properties is analysed in a parallel paper. [ABSTRACT FROM AUTHOR]

Flash methods have become one of the most commonly used techniques for measuring the thermal diffusivity and thermal conductivity of various kinds of solids and liquids such as metals, carbon materials, ceramics, and polymers. Easy sample preparation, small sample dimensions, fast measurement times, and high accuracy are only some of the advantages of this non-destructive measurement technique. However, the accuracy of measurement and level of uncertainty of the resulting data are becoming increasingly important for countless industrial applications. Instruments must be checked to determine the uncertainty of the system at different temperature and application ranges. One way of checking the accuracy of the results is to cross-check the unit with certified reference materials. However, there is a lack of standard materials for thermal diffusivity/thermal conductivity all over the world. Furthermore, for some available standards, the thermophysical properties are known only over a limited temperature range. Presented in this work are thermophysical property measurements on a certified thermal conductivity standard, Stainless Steel 310. Tests were carried out between −125 and 1000C. [ABSTRACT FROM AUTHOR]

Intense precipitation may occur in high-temperature materials during service. This precipitation significantly affects the mechanical properties. Coarse precipitates can reduce ductility and toughness dramatically. To investigate the phenomenon, precipitation in the austenitic stainless steel AISI 310 is quantified in a parallel paper. The samples were aged up to 5000 h at 800°C. Especially, σ-phase and M23C6-carbides were analysed. A model for the influence of coarse particles on ductility has been developed and successfully applied to the measured values. A model due to Chen and Mott has been used to compute the effect of particles on toughness. A satisfactory agreement with the observations was obtained. [ABSTRACT FROM AUTHOR]

This work is focused on the development of creep and stress relaxation models on Inconel 625 and Stainless Steel 310 materials for additive manufacturing. At the end, the operational lifespan of an industrial-scale additive manufactured recuperator is evaluated. An industrial-scale recuperator for burners with a highly complex geometry is manufactured using Continuous Wave SLM and Pulsed Wave Selective Laser Melting techniques. The recuperator operates under steady but high thermal loads, reaching temperatures of up to 875 °C. Therefore, its service life is assessed, considering creep and stress relaxation phenomena. Two different materials are evaluated: Inconel 625 and Stainless Steel 310. Tensile testing has been conducted on samples at various temperatures to acquire material parameters, incorporating appropriately the anisotropic nature of the materials. Creep parameters were determined through creep experiments and data from the literature, and the recuperator response was simulated by FEA modelling. Analytical creep and stress relaxation models were proposed based on the simulation results for each material to predict their creep response. The service life was determined by applying a custom failure criterion based on the creep testing data. The Inconel 625 recuperator exhibits a service life that is significantly higher compared to any burner's life, while the Stainless Steel 310 recuperator exhibits approximately 27 years of service life. Both materials are considered suitable; however, Inconel 625 offers higher resistance to creep according to creep tests, and due to its lower thermal expansion coefficient, the resulting thermal stresses are lower. [ABSTRACT FROM AUTHOR]

MgCl2-NaCl-KCl salts mixture shows great potential as a high-temperature (> 700 °C) thermal energy storage material in next-generation concentrated solar power plants. Adding Mg into molten MgCl2-NaCl-KCl salt as a corrosion inhibitor is one of the most effective and cost-effective methods to mitigate the molten salt corrosion of commercial Fe-Cr-Ni alloys. However, it is found in this work that both stainless steel 310 and Incoloy 800H samples were severely corroded after 500 h immersion test at 700 °C when the alloy samples directly contacted with the over-added Mg in the liquid form. The corrosion attack is different from the classical impurity-driven corrosion in molten chloride salts found in previous work. Microscopic analysis indicates that Ni preferentially leaches out of alloy matrix due to the tendency to form MgNi2/Mg2Ni compounds. The Ni-depletion leads to the formation of a porous corrosion layer on both alloys, with the thickness around 204 μm (stainless steel 310) and 1300 μm (Incoloy 800H), respectively. These results suggest that direct contact of liquid Mg with Ni-containing alloys should be avoided during using Mg as a corrosion inhibitor for MgCl2-NaCl-KCl or other chlorides for high temperature heat storage and transfer. [ABSTRACT FROM AUTHOR]

Irradiation by a high power laser beam has been used since several years as an innovative approach for evaluating the reactivity of metallic materials with a pure oxygen atmosphere. Indeed, materials selection for oxygen service is a key factor of mitigating the ignition of equipment also called as oxygen fire. Pulled by the need having always more efficient industrial processes, the oxygen usages are evolving toward steadily higher pressures or temperatures. In such operating conditions, the evaluation of the metallic materials resistance to the oxygen fire ignition and their property to propagate based on the oxidation kinetic is the only way to avoid the oversizing of equipment. In this context, the use of laser in evaluating the reactivity of metallic materials is a well-adapted method enabling the accurate control of the energy deposition transmitted to the tested material during oxidation as well as giving access to the energy threshold required to trigger the oxygen fire ignition. This paper investigates the oxidation kinetics on nickel-based alloys (Inconels 600 and 625) and on stainless steel 310, using a laser or a furnace preheating on small metallic parts. The scope of the study is the oxidation step taking place before the heating of the sample up to its ignition temperature. Process parameters are oxygen pressure (1 and 40 barg), oxygen content (air versus pure oxygen), duration, and temperature. A numerical model is used to couple a sample surface condition (machined, sandblasted, polished) with laser parameters (power, duration) needed to reach a predetermined preheating temperature of the sample. In order to determine the threshold heat input for materials' ignition by a laser in the oxygen atmosphere, it is necessary to know the absorption coefficient of the laser at the sample surface. This parameter is measured for various oxide layer thicknesses. [ABSTRACT FROM AUTHOR]

An experimental investigation was performed using a tungsten carbide tool to study the micro-electrical discharge machining behavior of two different grades of stainless steel (310 and 316 SS). The machining parameters considered to investigate the machining behavior of the chosen materials were (a) V: voltage (V), (b) C: capacitance (pf), (c) Ton: pulse-on time (µs), and (d) Toff: pulse-off time (µs). The machining behavior of stainless steel was evaluated in terms of material removal rate and tool wear rate. Taguchi L16 orthogonal array and gray relational analysis techniques were employed to design and optimize the machining conditions for both responses. Scanning electron microscopy, energy-dispersive spectroscopy, and optical microscopic analyses were also performed to identify the characteristics of the machined surface, characteristics of the micro-tool, and the elemental composition of the machined surface. The optimum machining condition for 310 steel was found as 150 V, 100 pf, 30 µs (Ton), and 20 µs (Toff). On the other hand, the optimum parametric condition for 316 steel was 200 V, 1000 pf, 20 µs (Ton), and 25 µs (Toff). [ABSTRACT FROM AUTHOR]

In this work, SiC (Silicon carbide), FeCrAl (ferritic), SS-310 (stainless steel 310) and Zirconium are simulated by MCNPX (Monte Carlo N‐Particle eXtended) code as cladding materials in advanced PWR (Pressurized Water Reactor) assembly. A number of reactor safety parameters are evaluated for the candidate cladding materials as reactivity, cycle length, radial power distribution of fuel pellet, reactivity coefficients, spectral hardening, peaking factor, thermal neutron fraction and delayed neutron fraction. The neutron economy presented by Zr and SiC models is analyzed through the burnup calculations on the unit cell and assembly levels. The study also provided the geometric conditions of all cladding materials under consideration in terms of the relation between fuel enrichment and cladding thickness from the viewpoint to achieve the same discharge burnup as the Zircaloy cladding. It was found that the SiC model participated in extending the life cycle by 2.23% compared to Zr. The materials other than SiC largely decreased discharge burnup in comparison with Zircaloy. Furthermore, the claddings with lower capture cross-sections (SiC and Zr) exhibit higher relative fission power at the pellet periphery. The simulation also showed that using SiC with a thickness of 571.15 μm and 4.83% U-235 can satisfy the EOL irradiation value as Zr. For reactivity coefficient, the higher absorbing materials (SS-310 and FeCrAl) exhibit more negative FTCs, MTCs and VRCs at the BOL But, at the intermediate stages of burnup Zr and SiC have a strong trend of negative reactivity coefficients. Finally, the delayed neutron fraction of SiC and Zr models is the highest among all the four models. [ABSTRACT FROM AUTHOR]

As concentrated solar power (CSP) systems evolve, the new generation of CSP systems will utilize chloride molten salts, which are cost-effective and have high operating temperatures, but are highly corrosive. In order to reduce the corrosiveness of chloride salts, we investigated the addition of different levels of Mg to chloride salts to study the effect on corrosion. In this paper, the corrosion behavior of 310S stainless steel with aluminum in high-temperature molten salt NaCl-KCl-MgCl2 was studied. By adding different contents of magnesium corrosion inhibitor, the corrosion mechanism and the effect of the corrosion inhibitor were explored. The results show that the lowest corrosion rate of 6.623 mm/y was obtained for the aluminum-formed 310S with 0.05 wt.% Mg. However, the corrosion rate rises when the Mg content exceeds 0.05 wt.% compared to the corrosion rate of corroded specimens without Mg. Changing the added Mg content does not affect the corrosion products. For 310S stainless steel with aluminum, its corrosion inhibition was best achieved by adding 0.05 wt.% Mg to the chloride molten salt. [ABSTRACT FROM AUTHOR]

We have designed and realized a temperature and pressure controlled cell for Neutron Reflectometry (NR) and Small Angle Neutron Scattering (SANS) that is compatible with simultaneous optical transmission and resistivity measurements. The cell can accommodate samples up to 102 mm (4 inch) in diameter, can be pressurized from vacuum up to 10 bar gas pressure and the sample temperature can be controlled up to 350°C. The four single crystal quartz windows ensure both a good neutron and optical transmission and hence can be used in combination with in-situ optical transmission measurements. We present the cell and illustrate its performance with a series of neutron reflectometry experiments performed on Ta based thin films under a hydrogen containing atmosphere. [ABSTRACT FROM AUTHOR]

SS316 is the most commonly used material among the existing stainless steels. SS316-based composite materials provide tailor-made stuff to the various automotive and machinery components due to their competent properties. In the current work, SS316, EWAC, and Cr7C3 powders have been selected for the development of cast specimens in the domestic microwave applicator. The cast of the SS316+15EWAC+5Cr7C3, SS316+15EWAC+10Cr7C3, and SS316+15EWAC+15Cr7C3 compositions has been prepared using a novel technique of microwave hybrid heating. The sample size of 30 × 6 mm2 has been used for flexural strength analysis. The flexural modulus, flexural strength, maximum load, strain at break, and strain at peak load have been tested on a universal testing machine. The maximum values of flexural strength, flexural modulus, peak load, and microhardness were found 469.86 MPa, 10,2321.79 MPa, 4510.65 N, and 585.93 ± 203.33 HV respectively for SS316+15EWAC+15Cr7C3 cast, and maximum strain at peak load and the maximum strain at breaking load were 3.07 and 4.29% respectively for SS316+15EWAC+10Cr7C3 cast. The highest microhardness of 615 HV has been obtained at the carbide phase in the case of SS316+15EWAC+15Cr7C3 cast. The XRD presented the leading peaks of σ-Fe, μ-Fe3Ni2, τ-Cr23C6, α-MoNi4, γ-Mo2C, and β-Fe5C2. The microstructural morphology of the composite casting revealed the proper coalescence of the matrix, homogeneous dispersion of reinforcements, dendrites formation, and equiaxed grain growth. Overall the metallurgical and mechanical properties of the composite cast were improved. [ABSTRACT FROM AUTHOR]

Currently, a significant number of automobiles are equipped with internal combustion engines. In urban areas, a significant number of transportation methods have detrimental environmental effects through the release of pollutants resulting from the combustion of fossil fuels. In addition to the emission of toxic pollutants, internal combustion engines experience significant energy losses through exhaust emissions. Advanced technological applications have the potential to recover of a portion of the waste heat from exhaust ducts. Evaluations conducted by scholars across several disciplines highlight diverse perspectives on the recycling of thermal energy from exhaust gases as a means of mitigating pollution sources. However, this review focuses on the utilization of thermoelectric generators for harvesting a fraction of the aforementioned dissipated energy. The energy harvesting system is comprised of three components: the heat exchanger, which serves as the heat source; the cooler, which functions as the heat sink; and the thermoelectric generators, which act as the heat engine sandwiched between the heat exchanger and the cooler. This review examines the diverse exterior designs of heat exchangers and coolers and categorizes them accordingly. Additionally, it identifies the optimal installation locations for harvesting systems and explores the impact of design variations, choice of metals for manufacturing, and internal topography on the generation of electrical power. The primary findings of this review emphasize the significance of prioritizing the design of heat exchangers over coolers. This is because the uniformity of the temperature distribution within the heat exchanger plays a crucial role in governing the overall performance. Moreover, the installation of the system on petrol engines was seen as more cost-effective in comparison to its installation on diesel engines, primarily due to the higher magnitude of energy emitted from the exhaust gases of the former as opposed to the latter. To the best of the author's knowledge, this review classification has never been performed before. This can be considered a brief path map and a starting point for future work by researchers and investigators in designing heat exchangers and coolers and choosing the locations of TEG system installations. Then profitable investment from the data that has been prepared and summarized. [ABSTRACT FROM AUTHOR]

In order to reduce interfacial contact resistance (ICR) and enhance corrosion resistance of 310 stainless steel (310 SS) for bipolar plates (BPs) of polymer electrolyte membrane fuel cell (PEMFC), TiN with styrene-butadiene rubber (SBR) coating was prepared by using electrophoretic deposition. Microstructure of TiN-SBR coated 310 SS prepared under different conditions was characterized by scanning electron microscopy (SEM), and a uniform, dense and well-bonded TiN-SBR coating was prepared at 30 V for 10 s in the suspension liquid containing 6.0 g/L SBR. Polarization behavior in the simulated service environment of PEMFC (1 M H2SO4 at 298 K) and ICR of the TiN-SBR coating deposited under the optimized conditions were investigated. The results showed that the TiN-SBR coating successfully decreased the anodic polarization current and ICR, indicating excellent interfacial contact resistance and corrosion resistance. [ABSTRACT FROM AUTHOR]

The so-called screening current in a high temperature superconductor (HTS) is a well-known phenomenon that has detrimental effects on performance of an HTS magnet. To date, many research efforts have been devoted to suppressing screening current in an HTS magnet. Here, we report a customized electric-heater, named "Thermal Eraser," to mitigate the screening current. The key idea is to optimally control the spatial temperature distribution in an HTS magnet using the customized heater and the consequent temperature-dependent local critical current of HTS wires of the magnet. To validate the idea, a Thermal Eraser was designed, constructed, and installed in an actual single-pancake HTS coil. The Thermal Eraser with the test coil system was operated at temperatures ranging 7–40 K in our in-house conduction-cooling cryogenic facility. The feasibility of the Thermal Eraser was demonstrated in terms of two aspects: (1) creation of the designated spatial temperature distribution within the HTS test coil as designed and (2) quantitative evaluation of its effectiveness to mitigate screening current using both experimental and numerical results. We confirmed that the screening current induced field in the test coil was reduced by 0.6 mT after activation of the Thermal Eraser, which implies 60% reduction of screening current in the HTS test coil. The results demonstrate that the Thermal Eraser is a viable option to effectively reduce the screening current in an HTS magnet. [ABSTRACT FROM AUTHOR]

In this work, we present a deep neural network model to automatically learn the capabilities of discrete manufacturing processes such as machining and finishing from design and manufacturing data. By concatenating a 3D Convolutional Neural Network (3D CNN) with a simple Multilayer Perceptron (MLP), we show that the model can learn the capabilities of a manufacturing process described in terms of the part features and quality it can generate, and the materials it can process. Specifically, the proposed method takes the part feature geometry, material properties, and quality information contained in a part design as inputs and trains the deep neural network model to predict the manufacturing process label as output. We present an example implementation of the proposed method using a synthesized dataset to illustrate automatic manufacturing process selection. The performance of the proposed model is compared with the performance of interpretable data-driven classification methods such as decision trees and random forests. By comparing the performance with different combinations of input information to be included during training, it is evident that part quality information is necessary for characterizing the capabilities of finishing processes while material information further improves the model's ability to discriminate between the different process capabilities. The superior prediction accuracy of the proposed deep neural network model demonstrates its potential for use in future data-driven Computer Aided Process Planning (CAPP) systems. [ABSTRACT FROM AUTHOR]

This paper describes the design and performance checks of the NPL axial heat flow apparatus developed at the National Physical Laboratory for measurement of thermal conductivity. This apparatus is based on an absolute steady-state technique and is suitable for measuring specimens with thermal conductivities in the range from $$10\,\hbox {W}{\cdot }\hbox {m}^{-1}{\cdot } \hbox {K}^{-1}$$ to $$240\,\hbox {W}{\cdot } \hbox {m}^{-1}{\cdot } \hbox {K}^{-1}$$ and at temperatures between $$50\,^{\circ }\hbox {C}$$ and $$500\,^{\circ }\hbox {C}$$ . A uniform heat flow is induced in a cylindrical bar-shaped specimen that is firmly clamped between a guarded heater unit at the top and a water-cooled base. Heat is supplied at a known rate at the top end of the specimen by the heater unit and constrained to flow axially through the specimen by a surrounding edge-guard system, which is closely matched to the temperature gradient within the test specimen. The performance of this apparatus has been checked against existing NPL thermal-conductivity reference materials NPL 2S89 (based on Stainless Steel 310) and BSC Pure Iron (pure iron supplied by the British Steel Corporation with 99.96 % purity). The measured data produced by the newly designed NPL axial heat flow apparatus agree with the reference data for NPL 2S89 within 2 % and with that of BSC Pure Iron to within 3 % at temperatures from $$50\,^{\circ }\hbox {C}$$ to $$500\,^{\circ }\hbox {C}$$ . This apparatus is being used to provide accurate measurements to industrial and academic organizations and has also been used to develop a new range of NPL reference materials for checking other experimental techniques and procedures for thermal-conductivity measurements. [ABSTRACT FROM AUTHOR]

Waste heat recovery stands out as a promising technique for tackling both energy shortages and environmental pollution. Currently, this valuable resource, generated through processes like fuel combustion or chemical reactions, is often dissipated into the environment, despite its potential to significantly contribute to the economy. To harness this untapped potential, a traveling-wave thermo-acoustic generator has been designed and subjected to comprehensive experimental analysis. Fifty-two data corresponding to different working conditions of the system were extracted to build ANN, ANFIS, and ANN-PSO models. Evaluation of performance metrics reveals that the ANN-PSO model demonstrates the highest predictive accuracy ( R 2 = 0.9959 ), particularly in relation to output voltage. This research demonstrates the potential of machine learning techniques for the analysis of thermo-acoustic systems. In doing so, it is possible to obtain an insight into nonlinearities inherent to thermo-acoustic systems. This advancement empowers researchers to forecast the performance characteristics of alternative configurations with a heightened level of precision. [ABSTRACT FROM AUTHOR]

The flexural behavior of iron-based composite castings has been analyzed under three-point loading conditions. The metal matrix composite casting of five varying compositions of powders by weight, that is, SS316, SS316+15EWAC, SS316+15EWAC+5WC−12Co, SS316+15EWAC+10WC−12Co, and SS316+15EWAC+15WC−12Co has been cast in a domestic microwave oven of maximum power and frequency of 0.9 kW and 2.45 × 103 MHz respectively. The casting of size 30 × 6 mm2 is prepared. The prepared sample's mechanical properties, such as ultimate peak load, flexural strength, strain at peak load, strain at break and flexural modulus, are tested on Dak System UTM having load cell 10 kN as per ASTM 1161-18 standard. The flexural strength and peak load for SS316+15EWAC+10WC−12Co, strain at peak load for SS316+15EWAC+5WC−12Co, and flexural modulus and microhardness for SS316+15EWAC+15WC−12Co were found maximum value. The maximum microhardness value is obtained in the carbide phase. The microstructure of the cast samples shows equiaxed grain growth with identical melting of the matrix. The XRD pattern of the samples confirmed the presence of various intermetallic and carbide phases. [ABSTRACT FROM AUTHOR]

Flexural behavior of high-Cr white cast iron (WCI) reinforced with different shapes, i.e., I- and T-sections, and volume fractions of austenitic stainless steel (310 SS) were examined under three-point bending test. The dimensions of casted beams used for bending test were (50 × 100 × 500 mm 3). Carbon and alloying elements diffusion enhanced the metallurgical bond across the interface of casted beams. Carbon diffusion from high-Cr WCI into 310 SS resulted in the formation of Cr-carbides in 310 SS near the interface and Ni diffusion from 310 SS into high-Cr WCI led to the formation of austenite within a network of M 7C 3 eutectic carbides in high-Cr WCI near the interface. Inserting 310 SS plates into high-Cr WCI beams resulted in a significant improvement in their toughness. All specimens of this metal matrix composite failed in a ductile mode with higher plastic deformation prior to failure. The high-Cr WCI specimen reinforced with I-section of 310 SS revealed higher toughness compared to that with T-section at the same volume fraction. The presence of the upper flange increased the reinforcement efficiency for delaying the crack growth. [ABSTRACT FROM AUTHOR]

Microstructural evolution and solidification cracking susceptibility of dissimilar metal welds between Type 310 austenitic stainless steel and Inconel 657, a nickel-based alloy, were studied using a combination of electron microscopy analysis and Varestraint testing techniques. In addition, the effect of filler metal chemistry on the fusion zone composition, microstructure, and resultant weldability was investigated. The good cracking resistance of welds prepared with Inconel A was due to a small amount of secondary phase (NbC) and narrow solidification temperature range. The relatively poor cracking resistance of welds prepared with Inconel 82 and Type 310 stainless steel (310 SS) was a result of a wide solidification temperature range and an increase in the amount of secondary phases. Consequently, it is concluded that for the joint between Inconel 657 and 310 SS, filler material of Inconel A offers the best weldability. [ABSTRACT FROM AUTHOR]

Purpose: Because many cutting fluids contain hazardous chemical constituents, industries and researchers are looking for alternative methods to reduce the consumption of cutting fluids in machining operations due to growing awareness of ecological and health issues, government strict environmental regulations and economic pressures. Therefore, the purpose of this study is to raise awareness of the minimum quantity lubrication (MQL) technique as a potential substitute for environmental restricted wet (flooded) machining situations. Design/methodology/approach: The methodology adopted for conducting a review in this study includes four sections: establishment of MQL technique and review of MQL machining performance comparison with dry and wet (flooded) environments; analysis of the past literature to examine MQL turning performance under mono nanofluids (M-NF); MQL turning performance evaluation under hybrid nanofluids (H-NF); and MQL milling, drilling and grinding performance assessment under M-NF and H-NF. Findings: From the extensive review, it has been found that MQL results in lower cutting zone temperature, reduction in cutting forces, enhanced tool life and better machined surface quality compared to dry and wet cutting conditions. Also, MQL under H-NF discloses notably improved tribo-performance due to the synergistic effect caused by the physical encapsulation of spherical nanoparticles between the nanosheets of lamellar structured nanoparticles when compared with M-NF. The findings of this study recommend that MQL with nanofluids can replace dry and flood lubrication conditions for superior machining performance. Practical implications: Machining under the MQL regime provides a dry, clean, healthy and pollution-free working area, thereby resulting the machining of materials green and environmentally friendly. Originality/value: This paper describes the suitability of MQL for different machining operations using M-NF and H-NF. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0131/ [ABSTRACT FROM AUTHOR]

The blackening of materials is widely used in the automobile industry, defense applications, aerospace applications, and solar applications. Methods such as electroless chemical process, conversion coating, physical vapor deposition, chemical vapor deposition, and diamond-like carbon are some of the commonly employed techniques to produce black coatings on various metals. Hot aqueous alkaline treatment is a chemical conversion coating process. In this study, hot alkaline treatment is used to blacken surgical equipment made of stainless steel 410, which is a novel approach. The effect of process variables such as immersion time, salt solution temperature, and wt% of sodium dichromate on the anti-reflective property of ferrous ferric oxide (magnetite, Fe3O4) coating has been optimized using the Taguchi method and response surface methodology. The experiments were designed using a Taguchi orthogonal array and a Box-Behnken design. The influences of coating parameters on average percentage reflectance were quantified by the signal-to-noise ratio, main effect plot, analysis of variance, and two-dimensional and three-dimensional plots. The comparison of experimental and confirmatory tests shows that both procedures optimized the parameters successfully. The lowest average percentage reflectance value of 8.013% was obtained at 56.976 min immersion time, 124.998°C salt solution temperature, and 348.689 g/l wt% of sodium dichromate in the composition by Box-Behnken design methodology. [ABSTRACT FROM AUTHOR]

To shift the usual path of ejection of the energy accompanying the exhausts of internal combustion engines, extensive studies have been carried out regarding the powder metallurgy technology used for the manufacturing and forming of various thermoelectric generator couple shapes and how to enhance their power efficiency. But in the present scoping review, the goal is to explain how the temperature difference on the thermoelectric generator sides was affected by improving the external and internal structures of the hot side (heat exchanger) and cold side (cooler) to enhance the amount of harvested power. It was also discussed how cooling techniques and the kinds of metals used to make heat exchangers and coolers affected the output power was explained too. The scoping review was devoted to displaying previous works and systems on how to harvest energy from the exhausts of automobile internal combustion engines and reviewing the impact of the dimensions, arrangements, and shapes of internal obstacles or fins on the amount of temperature difference and produced power. The conclusions are summarized as a path map and viewpoints for the future work of researchers in designing heat exchangers and coolers and profitable investment from the data that has been prepared and summarized in tables (2 and 4). It should also be noted two major factors, the first being the pressure drop, which is necessary to avoid engine power losses across the heat exchanger, and the second being the reduction of extra mass and fuel consumption due to the installation of the heat exchanger, it is possible to design the muffler so that the thermoelectric generators can be installed on it. [ABSTRACT FROM AUTHOR]

This paper develops an FEA modeling protocol for simulating ultra-high-performance concrete-filled double-skin tubes (CFDST) for heat transfer analysis purposes. The research presented in this paper refines the existing FE methodologies for circular, rectangular, elliptical, hexagonal, and octagonal CFDST members under fire conditions. Various modeling parameters, such as thermal properties of different materials and the thermal contact conductance at the interaction surfaces, are incorporated and controlled via an automatic algorithm for proficient modeling. It is found that the available models for calculating the thermal contact conductance at the interfaces between metal tubes and the concrete cores have a strong dependence on the cross-sectional shape. Thus, a refined model of the thermal conductance for the hexagonal and octagonal CFDST columns is proposed. Extensive experimental results (212 fire tests) are assembled from the literature to verify the proposed FE methodology. Good agreements with test results are demonstrated when predicting the temperature fields within the considered CFDST cross-sections. Consequently, extensive results from the proposed algorithm can provide an initial basis for parametric studies and for forthcoming nonlinear stress analysis simulations of CFDST columns under fire, which are primary goals in future studies. Finally, complying with the existing design codes, a new simplified analytical model based on the finite difference (FD) method is presented for predicting the temperature developments through CFDST columns. [ABSTRACT FROM AUTHOR]

High temperature molten salt corrosion is of utmost importance for selecting and qualifying structural materials for critical applications. Pyrochemical reprocessing of spent metallic fuels of the future fast breeder reactors in India is widely considered. One of the main processes of pyrochemical reprocessing is electrorefining. Electrorefining is generally conducted in LiCl–KCl molten salt at 500–600 °C under an inert atmosphere. Research groups worldwide are involved in developing corrosion resistant materials and investigating the corrosion behaviour of various structural materials for LiCl–KCl applications under different environments. A wide variety of materials, including metals, alloys, intermetallics, single crystals, glass and ceramics, have been investigated in molten LiCl–KCl salt. This review focuses mainly on the corrosion assessment of materials for LiCl–KCl application; a complete literature review with emphasis on the corrosion issues of materials is provided. This paper reviews the corrosion issues of metals and alloys in molten salts and the selection criteria of corrosion-resistant materials for molten salts. Understanding the molten salt corrosion mechanisms and future research scope are also discussed. [ABSTRACT FROM AUTHOR]

This paper presents a computational method to investigate cooling performance of NASA-C3X cascade vane coated with thermal barrier coating (TBC), for which experimental data are available. The vane was cooled internally by air flows through radially oriented 10 channels. A three-dimensional conjugate heat transfer simulation has been performed which allows the conduction-convection on metal vane by eliminating need of multiple boundary solutions. The predicted aerodynamic and thermal loads with the effect of turbulent intensity is found to be good agreement with experimental data and inclusion of TBC leads to quantitative reduction in vane metal temperature. [ABSTRACT FROM AUTHOR]