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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]

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]

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 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]

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]