The Hastelloy C276 superalloy is one of the versatile and promising alloys considered for high-temperature applications. In the present work, the crystallographic properties and nanomechanical behaviour of Hastelloy C276 superalloy manufactured via gas metal arc welding (GMAW) based wire-arc additive manufacturing (WAAM) were evaluated. The WAAM-processed C276 superalloy mainly comprises columnar dendrites with the predominant <100> and <111> textures at the middle region. Also, p phases rich in Mo and W were noticed within the interdendritic regions of the austenitic matrix. Small-scale mechanical testing revealed that the WAAM-processed Hastelloy C276 superalloy exhibited a reduced elastic modulus compared to its wrought counterpart. The average nanohardness (H) and reduced elastic modulus (Er) in the horizontal direction were 5.40 ± 0.51 GPa and 192.42 ± 4.50 GPa, and 4.28 ± 0.14 GPa and 122.26 ± 2.0 GPa in the vertical direction. From the nanoindentation responses, the dendritic cores have a reduced nanohardness than that of the interdendritic regions due to the localized segregation of Mo and W in the interdendritic regions, resulting in solid solution hardening. The H3/Er2 ratio revealed the comparable plastic deformation resistance of WAAM-processed Hastelloy C276 in the horizontal and vertical directions at the nanoscale level.

Sustainable manufacturing, a term that has been used in the recent past on numerous occasions. A primary reason for it being in limelight, is that it does not cause any damage to the environment and also to the personal involved. Additionally, another important parameter of concern is the energy consumed during the machining process. One major reason for higher energy consumption is because of the presence of tool vibration. There have been several attempts made to reduce vibration and though they have been proved to be effective, they could be not classified under sustainable manufacturing. When used as a semi-active damper in metal cutting, magnetorheological fluid (MRF) has proven to be successful in vibration suppression. MRF is an intelligent non-Newtonian fluid that can change its viscosity instantly when a magnetic field is applied to it. They've utilised it as a damper in a number of areas because of this quality and its toughness. One significant drawback is the settling of magnetic particles floating in a non-magnetic fluid. When the current provided to the coil is increased, the settling rate becomes much worse. Increased current increases the amount of heat created in the coil, which heats the non-magnetic fluid and reduces its viscosity. Stabilizers are added to MRF to address this issue, and particle size has an immediate impact on settling. In this study, activated carbon and titanium were used as stabilisers, and the size of the magnetic particles was adjusted to see how it affected the viscosity of MRF. The testing results showed that adding stabilisers to MRF enhanced the viscosity and thus the cutting capability of SS410 steel during dry hard turning.

Wire arc additive manufacturing (WAAM) has become an inevitable manufacturing technology in the present decade. This article discusses optimizing process variables for fabricating Hastelloy C276 alloy via WAAM. The controlling parameters are gas flow rate (GFR), deposition speed, and welding current, while the depth of penetration, top reinforcement, and bead width are the output parameters considered for optimization. The magnitude of interaction effects between control parameters is equal to that of individual impact on the weld bead characteristics evident from analysis of variance results. Grey relational analysis revealed the optimal parameters (trial 1 with I = 120 A, S = 200 mm/min, GFR = 15 L/min) chosen through its robust optimization procedure. S/N ratio analysis revealed the most influencing parameters at the factor level (current level 1, speed level 1). The Grey Wolf optimizer (GWO) algorithm was used as a precision and confirmation experiment. The GWO optimization results further confirmed that the GFR of 15 L/min, speed of 200 mm/min, and current of 120 A were the optimized parameters used in this design space. Further, normal probability plots with minimal error of around 1% reinforce that the parameters chosen in this design space are well within the optimal limits. The surface plots reported the relationship and variation between control and resulting factors.

Laser-welding is a promising technique for welding NiTi shape memory alloys with acceptable tensile strength and comparable corrosion performance for biomedical applications. The microstructural characteristics and localized corrosion behavior of NiTi alloys in a simulated body fluid (SBF) environment are evaluated. A microstructural examination indicated the presence of fine and equiaxed grains with a B2 austenite phase in the base metal (BM), while the weld metal (WM) had a coarse dendritic microstructure with intermetallic precipitates including Ti2Ni and Ni4Ti3. The hardness decreased from the BM to the WM, and the average hardness for the BM was 352 ± 5 HV, while it ranged between 275 and 307 HV and 265 and 287 HV for the HAZ and WM, respectively. Uni-axial tensile tests revealed a substantial decrease in the tensile strength of NiTi WM (481 ± 19 MPa), with a reduced joint efficiency of 34%. The localized corrosion performance of NiTi BM was superior to the WM, with electrochemical test responses indicating a pitting potential and low corrosion rate in SBF environments. The corrosion rate of the NiTi BM and WM was 0.048 ± 0.0018 mils per year (mpy) and 0.41 ± 0.019 mpy, respectively. During welding, NiTi’s strength and biocompatibility properties changed due to the alteration in microstructure and formation of intermetallic phases as a result of Ti enrichment. The performance and safety of welded medical devices may be impacted during welding, and it is essential to preserve the biocompatibility of NiTi components for biomedical applications.

High-strength martensitic stainless steel 410 (MSS 410) was successfully fabricated without defects via wire arc additive manufacturing (WAAM). The microstructural features, mechanical properties, and corrosion performance of WAAM-processed MSS 410 were examined. Microstructural analysis revealed the existence of equiaxed and coarse columnar dendrites and the formation of residual delta-ferrite and retained-austenite (RA) was confirmed within the martensitic matrix. The fraction of residual ferrite and RA varied along the building direction due to complex thermal cycles. Uni-axial tensile results exhibited anisotropic behavior and are related to layered microstructure. Microhardness values varied from bottom to top (384-460 HV). Ductile mode of failure was noticed, and the existence of RA influences the ductility. The corrosion behaviour of the WAAM 410 specimens in 3.5% NaCl solution was considerably acceptable, and the corrosion rate ranged between 0.05 and 1.37 mpy. This shall be attributed to the absence of defects, microstructural features, and ferrite fraction in the WAAM 410 samples. The mechanical properties and corrosion behaviour of the WAAM 410 were comparable to the wrought grade and are suitable for pressure vessel applications with adequate corrosion resistance.

The basic needs of people are met by the building, fabric, and farming sectors. In addition, the automobile industry significantly contributes to human mobility and is essential to India’s economic expansion. There are numerous research strategies available to improve the bus body building industries. Several investigative approaches for enhancing bus body building industries are available. However, several of these studies merely look at it from the perspective of shop floor activity. Accordingly, when it comes to the execution of process design approaches, there is little practical evidence for accepting Gemba kaizen’s attitude. Hence, the purpose of this article is to present a continuous improvement redesign framework tailored to a specific bus body building industrial sector. The proposed model is structured after a critical examination of Gemba and Kaizen. The results showed that by implementing the improvement initiatives, the number of process activities decreased from 44 to 25 (of which 43% were wasteful), and the cycle time decreased from an average of 112 hours to 68 hours, or 39% faster. The outcomes also show how the suggested model helped organizations reduce resource usage and enhance organizational effectiveness.

The limitations of commonly used materials such as steel in withstanding high temperatures led to exploring alternative alloys. For instance, Inconel 825 is a nickel-based alloy known for its exceptional corrosion resistance. Thus, the Inconel 825 is used in various applications, including aerospace, marine propulsion, and missiles. Though it has many advantages, machining this alloy at high temperatures could be challenging due to its inadequate heat conductivity, increased strain hardening propensity, and extreme dynamic shear strength. The resultant hardened chips generated during high-speed machining exhibit elevated temperatures, leading to tool wear and surface damage, extending into the subsurface. This work investigated the influence of varying process settings on the machinability of Inconel 825 metal, using both uncoated and coated tools. Optimal surface roughness (Ra) machining conditions were found by considering factors such as depth of cut, cutting speed, feed rate, and other parameters. The major objective of the present work was to enhance the machinability of Inconel 825 by considering the surface finish values. The results revealed that the favorable surface roughness (SR) values for machining Inconel 825 in an automated lathe were attained under lubricated coated conditions with a cutting speed of 100 m/min, feed rate of 0.06 mm/rev, and cutting depth of 0.7 mm.

Additive manufacturing (AM) techniques allow for greater design freedom than is possible with conventional manufacturing processes. Components fabricated via AM can be compact and more potent for electrical applications. This study used cold metal transfer (CMT) based wire arc additive manufacturing (WAAM) to build the WAAM 2319 wall. The microstructure is mainly composed of equiaxed and columnar dendrites along with a small fraction of pores. Precipitated θ phases formed due to complex thermal cycles during WAAM. The hardness of the WAAM 2319 alloy ranged between 68 HV0.2 to 86 HV0.2. The electrical resistivity of WAAM 2319 was 6.72±0.23 µΩ-cm resulting in the reduced conductivity of 25.66±1.10%IACS compared to the wrought AA2219 alloy having 30%IACS. The decrease in conductivity is attributed to the presence of coarse precipitates along with dendritic microstructure and copper solute concentration. Thus, WAAM-processed Al-Cu alloys can be used for future electrical applications.

Boiler Steels undergo severe degradation in corrosion resistance due to oxide scale formation at elevated temperatures. In this study, the comparative hot oxidation and hot corrosion resistance of wire arc additive manufactured SS 308L (WAAM 308L) was examined in hot air and Na2SO4-60% V2O5 molten salt environments at 700 degrees C. The corrosion resistance at elevated temperature was analysed using thermo-kinetic curves, corrosion products, and morphology of the oxides. The hot oxidation kinetics revealed that WAAM processed SS 308L specimens has excellent resistance and the weight gain reached 3.10 mg/cm(2) with thinner oxide scale formation. Hot corrosion kinetics of WAAM processed SS 308L specimens highlighted the higher weight gain (37.0 mg/cm(2)) in molten salt environment and is attributed to the acceleration of oxide scale formation by the salts at elevated temperatures. Also, the development of Ni3V2O8 and Fe2O3 along with the depletion of Cr2O3 significantly influenced the corrosion resistance at elevated temperatures. The findings of this study reveal the potential of WAAM to produce customized parts for high-temperature applications.

The present work reports the feasibility of wire arc additive manufacturing (WAAM) process to manufacture SS 347 components for high temperature applications. The microstructure of WAAM processed SS 347 (WAAM 347) comprised of austenite and residual delta-ferrite while the ferrite fraction varied between 1.40 and 4.20% along the building direction. Cyclic hot corrosion behaviour of WAAM 347 specimens were investigated under the Na2SO4-60%V2O5 molten salt at 700 degrees C by measuring the weight change. Higher weight gain was noticed in the samples exposed to hot corrosion because of the deposition of molten salt mixture. X-ray diffraction results revealed the formation of oxides like Fe2O3, FeV2O4, and Ni3V2O8 while the presence of NiCr2O4 and Cr2O3 lowers the corrosion rate at elevated temperatures. The absence of spallation due to the good adherence of oxide-scales highlights that WAAM 347 structures are suitable for elevated temperature applications.

In this work, the microstructural features, mechanical properties, and localized corrosion performance of a single-layered wall of nickel-based superalloy Inconel 617 produced via wire arc additive manufacturing (WAAM) were examined. Microstructural analysis revealed the existence of cellular and equiaxed dendrites in the bottom layers, while elongated columnar dendrites having a size up to 2 mm were observed in the middle and top layers due to different cooling rates and temperature gradients. Electron micrographs and energy-dispersive x-ray spectroscopy analysis confirmed the segregation of precipitates in the interdendritic regions of the austenitic matrix. Carbides such as Ti (C, N) and Cr23C6 existed in the interdendritic regions and are caused by the diffusion of Cr, Mo, and C elements during the WAAM process. Assessment of the mechanical properties revealed the excellent hardness (244-286 HV) and tensile properties of WAAM-printed IN617. The average yield strength, tensile strength, and elongation of IN617 specimens were 400 MPa, 724 MPa, and 43%, which is comparable with the ASTM B168-19 standard grade. The fracture surface analysis highlighted the ductile mode of fracture with dimples and micro-voids. Potentiodynamic polarization results illustrated the absence of significant anisotropic nature of the pitting resistance in 3.5% NaCl solution. The corrosion rate of the WAAM-printed IN617 specimens ranged between 1.02 and 1.07 mpy in 3.5% NaCl solution and the size of the pit was having a size of 30 to 100 µm. Electrochemical measurements indicate that the excellent pitting behavior is attributed to the formation of stable passive films along with higher corrosion potential and lower current density values. This study shows that the WAAM process can be potentially applied to other alloys for fabricating structures to obtain critical information on the corrosion damage.

The microstructural features, mechanical properties, and corrosion performance of Incoloy 825 manufactured using the wire arc additive manufacturing (WAAM) process are examined. Metallographic observations revealed that the microstructure was mainly dendritic, along with the presence of precipitates and laves phases. The average tensile properties of the WAAM-printed Incoloy 825 specimens are YS-274 +/- 6 MPa, UTS-576 +/- 15 MPa & EL-48 +/- 1.5% and YS-261 +/- 9 MPa, UTS-560 +/- 19 MPa & EL-53.5 +/- 2% in horizontal and vertical orien-tations, respectively. Microhardness values varied from bottom to top (226-262 HV). The electrochemical corrosion test outcomes in 3.5% NaCl solution highlighted the stability of the WAAM-printed Incoloy 825 samples with an outstanding corrosion rate of 0.59-0.70 mils per year (mpy). Experimental results confirmed the comparable mechanical properties and superior corrosion resistance of Incoloy 825 for marine environments.

Rice husk ash (RHA) is an agro-based waste used as a sustainable supplement in concrete. The RHA produced by controlled incineration completely blends in concrete mix by increasing the pozzolanic property since it holds silica without compromising on cement properties. After replacing RHA partially in cement, a fair refinement in porous structure increases strength and durability characteristics. The present paper investigates the application of statistical models to predict the characteristics using MATLAB software by ANN tool with networks like FFNN, LRNN, CFNN and ENN. The network performance characteristics such as RMSE, MAE, MRE, prediction accuracy percentage and computational time are used to find the optimal network. The dependent variables are 28th day compressive strength, ultrasonic pulse velocity test results and water absorption percentage. Two hundred and eleven mix design samples of RHA concrete were collected from the various reputed journals published within a decade. Water to binder ratio, cement, RHA, water, fine, coarse aggregate and super plasticizer were used as input parameters to develop the models and ultimately to predict strength and durability characteristics of RHA concrete. The comparison results of the various prediction showed that all the four networks performed roughly same, but based on overall performance characteristics, the developed CFNN model is identified as the optimal ANN, used for predictions in the future.

The oil and gas industries have been extensively utilizing 25Cr super duplex stainless steels because of their excellent mechanical properties and corrosion resistance. Wire arc additive manufacturing technology was employed to fabricate thin wall using ER2594 filler wire. The microstructural examination exposed the presence of ferrite, intragranular austenite, Widmanstätten austenite, grain-boundary austenite and secondary austenite. It was found that the austenite-ferrite fraction varied across the wall due to the complex cyclic thermal history during deposition. Detrimental phases such as sigma-σ or lambda-λ were not observed due to lower heat input and suitable inter-pass temperature. Micro-hardness measurements showed the gradual variation of hardness along the built direction (281–310HV0.2). Tensile specimens exposed anisotropy, and the tensile properties were better than the wrought counterparts and meet the minimum requirements as mentioned in ASTM A240/A240M-20a and ANSI/NACE MR0175/ISO 15156-1:2015.

The conventional image processing algorithms are not found to perform well in detecting crack problems. Generously the crack classification performance is also not clear with traditional deep learning neural network. To mitigate these issues, a convolutional neural network-based detection of bridge crack is presented in this work. The arous space pyramid pool (ASPP)-based feature extraction with depthwise separable convolution is modeled. With ASPP, the multiscale information of image features can be obtained, and the proposed convolution model provides large reception field so as to effectively fuse huge amount of contextual data on feature maps. Hence, the computational complexity of the model is greatly reduced. The results are verified in simulation which shows that the proposed method has achieved a highest detection accuracy of 96.68% which is higher than the conventional deep learning model.

In recent years, interest in the thermal properties of graphene constituents has seen rapid growth in the fields of science and engineering. The removal of heat in the continuous processes in the electronics industry has had major issues in thermal transmission in lower-dimensional assemblies. It has also shown fascinating topographies as the carbon allotropes and their derivative compounds expel heat. Numerous research articles reported within the past 15 years have demonstrated enhanced electron flexibility, exceptional thermal conductivity and mechanical behaviour, as well as excellent optical properties of graphene as a single atomic layer. This review article tries to provide a detailed summary of the heat exchange properties of graphene structures and graphene-based materials such as nanoribbons with few-layered graphene. Thermal and energy storage management systems have played a major role in the increase in marketable products in recent times. The purpose of this review is to summarize the current research on thermal properties with regard to the management and energy storage of graphene materials, focusing on characteristic properties, industrialization, modelling and simulation, and their applications in specific thermal storage systems.

The study investigates on temperature distribution of moving heat source performed on a coupon. Heat dissipation and penetrationcharacteristics are being investigated. Finite element solution of a moving heat source model is attempted by using ANSYS. Transient thermal analysis model was chosen to achieve heat input characteristics for the model. Volume of welding process, voltage and current were the parameters considered in designing the heat source. Heat source was formulated using Gaussian heat equation. The heat source was introduced on plates of different thicknesses (3mm, 4mm, 5mm and 8mm) and was found that the heat dissipation characteristics changed in accordance with the thickness of the coupons. The study suggests that the trial welds and bead on welds should be done on samples with similar thicknesses as it directly affects the metallurgical characteristics of the weld.

This work investigates the understanding between microstructure and corrosion behaviour of SDSS 2594 wall component fabricated using gas metal arc welding (GMAW) based wire arc additive manufacturing (WAAM) process, with the help of optical micrographs and electrochemical corrosion tests. Potentiodynamic polarization tests and Electrochemical impedance spectroscopy (EIS) analysis in 3.5% NaCl solution revealed excellent pitting resistance while the corrosion rate ranged between 1.51 and 1.61 mils per year (mpy) with pitting resistance equivalent number (PREN) > 40. The intergranular corrosion (IGC) test results confirmed the absence of sensitization and highlights that the formation of passive film is compact for corrosive environments. (C) 2020 Elsevier B.V. All rights reserved.

Welding is widely used in the final stage of the casting production and in fabricating the components for joining. The simplicity of titanium welding and its special effects on mechanical properties is therefore extremely important conditions in the case of engineering workings. The idea of this review is, to sum up the welding capability and its effects on mechanical properties of grade 5 titanium alloy tubes. It has been identified that the titanium welding is used in different fields throughout the world. The GTAW process is the best method to weld the titanium alloys.

The Aluminium 6063 have found wider applications in architectural fabrications, frames, pipe and tubing because of their intrinsic properties The Mechanical behavior of Aluminium alloy 6063 metal matrix composites (AMMC) reinforced with Borosilicate powder of 75 microns is investigated in this study. The Metal Matrix Composites (MMC’s) were prepared using various percentages of borosilicate reinforcements of 0, 2.5, 5, 7.5 and 10 % by wt. The main aim of the research was to determine the impact of borosilicate powder (75 microns) on the mechanical behavior of Al 6063. Mechanical tests such as tensile test, Vickers micro hardness measurements and compression tests were performed on the produced composite samples to determine the influence of the powder in the Aluminium alloy. The test results of the reinforced samples were compared with non-reinforced samples. By comparing all the test values it is inferred that AA 6063 has better properties when reinforced with 7.5% of 75micron size borosilicate reinforcements.