Straight tube butt welding with cold wire conditions is an increasingly used welding process in fabrication or manufacturing industries to increase productivity and improve weld quality. The existing literature studies on straight tube butt welding with cold wire conditions of T12 joints of boiler tubes are still limited. Hence, this study investigated the straight tube butt welding using cold wire conditions of T12 steel joints. Ultimate tensile strength and Vickers microhardness were measured to test the feasibility of butt-welded joints of T12. The weldment is characterized using Optical Microscopy (OM) to study the surface morphologies.

This study examined the effects of straight tube butt welding (STBW) with hot and cold wire conditions on T92 steels. The tube specifications are 4.5-mm thick and 44.5-mm outer diameter, utilizing a V-groove with a 70° angle for both welding processes. ER90SB-9 filler wire, with a diameter of 1.2 mm, was used. The weldment was characterized using radiographic analysis to confirm weld quality alongside optical microscopy (OM), x-ray diffraction (XRD), and scanning electron microscopy (SEM). Vickers microhardness measurements, toughness, and tensile tests were conducted to evaluate the mechanical properties of both welded samples and base metals. The tensile strength of the straight tube butt-welded T92 steel was 726 MPa under the hot wire condition and 552 MPa under the cold wire condition. The toughness of the straight tube butt-welded T92 steel was measured to be 41 J under hot wire welding conditions and 45 J under cold wire welding conditions. The average hardness values in the weld zone were 483.48 HV1 and 456.85 HV1 for hot and cold wire conditions, respectively. Radiographic analysis revealed seamless weld regions with no voids or pores, confirming high-quality joints. When compared to the hot wire condition, the hot wire method exhibited an improvement of 174 MPa (31.5

This study evaluates the effects of Equal Channel Angular Pressing (ECAP) on the mechanical properties and fatigue behaviour of Aluminium 6063, a material widely used in aerospace applications. ECAP was performed at channel angles of 90 degrees and 120 degrees with a radius of curvature of 20 degrees through route A at room temperature. The investigation focused on grain refinement and its impact on tensile strength, microhardness, and low-cycle fatigue (LCF) performance. ECAP 90 and ECAP 120 samples achieved fatigue lives of 7489 cycles and 5860 cycles, respectively, compared to 1286 cycles for Al 6063 T6 at a total strain amplitude of 0.4 %. Tensile strength increased significantly, with ECAP 90 and ECAP 120 samples showing enhancements of approximately 65 % (312 MPa) and 35 % (230 MPa) over the T6 sample (181 MPa). Microhardness values also improved, rising from 65 HV in T6 to 115 HV and 95 HV for ECAP 90 and ECAP 120, respectively. Stress-strain hysteresis analysis revealed stable modulus ratios near 1.006-1.007 for ECAP samples and minimal plastic strain amplitudes of 0.001 %, demonstrating effective resistance to cyclic deformation. These findings underscore the potential of ECAP in enhancing the structural integrity and durability of Al 6063 alloys under cyclic loading, offering significant benefits for aerospace component design.

The T92 martensitic steel is utilized in thermal power plants because of its better mechanical properties, and it is needed to enhance the strength and improve the properties using heat treatment. The research aims to determine how the microstructure changes in T92 martensitic steel when normalized at 1000 °C for an hour and tempered at 760 °C for 2 hours using various cooling techniques, including air cooling, furnace cooling, and water quenching. It is characterized by using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) equipped with energy-dispersive X-ray spectroscopy (EDS), and optical microscopy (OM). Tensile strength, hardness and toughness measurements were also performed on the heat-treated T92 steel specimens. After tensile testing of heat-treated samples of T92 steel, the fracture surface was characterized using SEM to determine the fracture mode. The strength and hardness of T92 material increased with a normalizing of 1000 °C, whereas they decreased with a tempering of 760 °C. Compared to various material conditions, the tempering of 760 °C with air-cooled hold the tensile strength of 887 MPa, hardness of 267.42 HV and toughness of 135 J was shown to be the optimal combination.

Evolution of microstructure and hardness in 42CrMo4 steel during quenching under the different cooling conditions were investigated. Mineral oil, polymer solution and water were selected as quenchants to provide different cooling conditions. Quenching experiments were also conducted under magnetic stirring and ultrasonic agitation of polymer solution. Cooling conditions during quenching had significant effect on phase transformation and hardness of 42CrMo4 steel. The quench hardened samples show martensite microstructure along with other micro-constituents. Needle like/acicular ferrite was observed with water quenching due to diffusion less transformation. Sample quenched under ultrasonic agitated medium showed formation of network of carbides. Higher hardness values were obtained with water quenching and ultrasonic agitated polymer quenching.

Magnetically impelled arc butt welding (MIAB) is a solid-state pressure welding technique used to join tubes and pipes, which does not require edge preparation and filler material. Heating the material on both the tube surface ends by producing a rotating arc using an electromagnetic force improves the arc rotation. Applying the forging pressure on the movable end of the tube will join with the other end surface of the tube. Unlike conventional welding, the weld formation is developed with a single-step process without several passes. The parameters such as welding current, exciting coil current, coil position, and gap size between the tubes influence the weld strength. This review focuses on MIAB welding stages with process parameters and MIAB welded of similar and dissimilar materials, including the microstructure of weld and joint performance and the process parameters that affect the property of welded materials and researcher inferences; applications were discussed.

In the industrial machining process, there have been major advances in near-net-shaped forming, which leads machining to be considered a significant modern phenomenon. Machining turns a huge number of metals into chips every year. This study aimed to determine the wear and mechanical properties of various cutting inserts. Polycrystalline diamond (PCD) and Ceramic Inserts were selected as coated inserts. It was discovered that tool wear at the cutting edge impacts various factors, including the amount of cutting forces created during machining; the surface finish of the workpiece is also compromised, resulting in reduced tool life. Owing to the frequent replacement of cutting tools, the decreased wear rate of cutting tools exponentially raises the costs that companies/machine shops would incur. After the second iteration, this insert began to develop crater wear, which resulted in a poor surface finish and high heat generation. However, the surface finish of this instrument was discovered to be the best during the first iteration. From the outcome, the PCD coated tool with feed speeds and low depth of cuts performed the efficient machining process. The surface finish is also accurate for PCD coated tool. The bat and whale algorithms’ optimization involved to find the best technical parameters to achieve the lowest possible error value based on rake and face wear. The bat and whale algorithms were used to determine the optimized rake and face wear values. The bat algorithm outperforms the whale algorithm in terms of wear value predictions.

Aluminium and its alloy are widely employed in various automobile and aircraft areas because of their unique specific strength and formability. Al alloys that have been employed in aerospace structural components will undergo dynamic loading, which leads to fatigue due to mechanical stress and thermal conditions. Considering studies toward the low cycle fatigue behaviour of Al alloys are significantly narrowed, this chapter sighted to the analysis of fatigue behaviour of Al 6063 alloy at the various total strain amplitude (TSA) of 0.4% and 0.8%, which performed through the low cycle fatigue testing machine at the frequency rate of 0.2 Hz. The test results show that for 0.4% TSA, the number of cycles to failure (N) is 1786, whereas as the TSA increases, N got reduced. For 0.8% TSA, the cycle to failure is 291 and samples undergone cyclic softening during the test. The rate of cyclic plastic strain raised up with the increase in the TSA. Crack propagation was observed along with the quasi-cleavage fracture for 0.4% TSA and cleavage fracture for 0.8% TSA.

Micro-electric discharge machining (Micro-EDM) is deployed for machining hard-to-machine materials, such as various grades of titanium alloys, heat-treated alloy steels, composites, tungsten carbides, and so forth. Mild steel is known for its easy machinability. However, conventional machining of mild steel can often lead to the built-up edge formation on the tool. There is a minimal focus on machining ductile materials using nonconventional machining processes. This is due to the rapid work hardening in cold forming conditions. In the present study, the aluminium alloy 6061 and mild steel AISI 304 were taken as a work piece. Input pulse on factors considered as three levels and orthogonal array utilized to optimize the EDM parameters. Numerical results confirm the influence of input parameters in the response. The highest MRR is obtained at Ton = 40 μs and Toff = 4 μs, and the least MRR is acquired at Ton = 20 μs and Toff = 3 μs. The fruit fly algorithm and the cockroach swarm algorithm were used to predict the optimal minimized MRR value. The experimental results show that the cockroach swarm algorithm was performing better than the fruit fly algorithm in the MRR minimization process.

Mechanically alloyed Al-5083 powders with different milling times are consolidated by equal channel angular pressing (ECAP) at room temperature (RT), at high temperature (HT), up to two passes in Route A and their mechanical and physical properties are studied in this paper. Microstructural and tensile tests of RT ECAPed samples reveal weaker bonds between the particles which result in poor tensile strength and ductility. Furthermore, the fractograph of RT ECAPed samples shows that the failure is due to particle pull-out as a result of poor metallurgical bonding. Unmilled (0 h) powder is found to have achieved 99.22% of its theoretical density and 45 HRB after the first pass in HT ECAP. However, microstructural studies and tensile tests revealed good metallurgical bonds between the particles. Furthermore, the fractured surface of compacts shows that the failure surface is dominated by the ductile fracture mode. HT ECAP followed by sintering is a suitable method for achieving metallurgical bonding between microparticles.

Dissimilar SAE 213 T11 and SAE 213 T91 boiler graded steel tubes are welded using magnetically impelled arc butt welding (MIAB) process, a hybrid welding process that combines the advantage of solid state and pressure welding technique. In this research, dissimilar tubes with an outer diameter of 44.5 mm and thickness of 4 mm with a length of 250 mm were joined by using the MIAB welding process. The microstructural behavior and changes of MIAB welded T11 and T91 tubes were analyzed at different zones of the butt-welded tubes using the metallurgical microscope and scanning electron microscope. Micro-Vickers hardness and potentiodynamic polarization test and radiographic testing were conducted. The hardness was taken at different zones along the transverse direction of the join. In the weld interface, the formation of a 2-3 µm martensitic structure leads to the hardness value of 281HV1, and at the base metal of T11 is 217HV1, T91 is 254HV1. The bead width at the welded region is approximately 10-12 µm with the narrow heat-affected zone. The metallurgical bonding between the T11 and T91 dissimilar tubes shows sound joint, which is confirmed with the radiography test.

Al-Si-Mg aluminum alloy samples were subjected to solution heat treatment at the temperature of 520 °C for 2 h to attain T42 condition. The heat-treated samples were quenched further in air and water mediums. After quenching, the fatigue life was analyzed with the total strain amplitude (TSA) of 0.4% at the cyclic frequency of 0.3 Hz using a low cycle fatigue testing machine. Air quenched sample has higher life with 1286 cycles than heat-treated and water quenched sample, which were having a fatigue life of 836 cycles and 708 cycles. Tensile mean stress was observed in all samples due to residual stress. Due to fatigue striation, ripple formation was observed in the air quenched sample, and the ripple having the size of 2-3 μm observed under SEM fractography. XRD peaks of Mg 2 Si and Al 3 Fe precipitates confirm the proper dispersion during the solution heat treatment.

Straight Tube Butt Welding is a process in which straight tubes are welded. Tubes with a 63.5 mm as outer diameter and 4 mm wall thickness are used as the base material in the following combination: Super 304H and T91. The filler material ERNiCR Fe-7A is selected based on the properties of two metals with 0.8 mm outer diameter. The study is to find out the near input parameters in gas metal arc welding of tempered martensitic steel T91 and austenitic steel super 304H with nickel-based filler wires. Trials are conducted with these alloy steel tubes by varying the input process parameters. All input parameters are taken and optimized by using Taguchi's method analysis and their optimized values are taken for their welding. High tensile strength is obtained from their optimized values, and the specimen is tested for the tensile and micro-hardness tests of welded joints. (c) 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the 3rd International Conference on Materials, Manufacturing and Modelling.

EN 47 spring steel is a 1% chromium-vanadium type spring steel, which is widely used for landing gears of smaller aircraft, leaf spring and coil spring of vehicles, heavy machinery crank pin, steering knuckles and disc springs for rigidly bolted sections. In this investigation, E-47 spring steel samples were heat treated and microstructure and hardness were observed. Then the samples were subjected to low cycle fatigue analysis along with fractograph. It is witnessed that for 8hrs heat-treated sample has taken 4222 cycles to fail and that is higher than 4hrs sample which is 3375 cycles to failure and an unheated sample which is having 2856 cycles to failure. The strain controlled fatigue life is greatly influenced by the type crack formation during the fatigue test. (C) 2019 Elsevier Ltd. All rights reserved.

Abstract Ionic liquids are molten salt substances combined with the nature of ions that have the capability of using additional elements to metal cutting fluids. Ionic liquids with less than 25 °C are called Room Temperature Ionic Liquids. i.e. which melts at room temperature and it turns into liquids. They are considered as green solvents mainly because of their chemical and physical properties. Since the traditional approach of using conventional cutting fluids have more disadvantages like high toxicity, non-biodegradable, skin irritation and affecting groundwater sources. To avoid these negative impacts, ionic liquids with metal cutting fluid improve the cutting performance and make the process environmentally friendly. The study\u0027s outcome is to view the composition of ionic liquids, physical effects, and working mechanisms of ionic liquids with cutting fluids.

An improvisation in the heat exchange equipment has become more vital nowadays, due to the increase in cost of energy and material existence. The rate of heat transfer will enhance by causing a change in the flow of fluid by breaking the thermal and viscous boundary layers, also by introducing the nanofluid. The main idea of this paper is to evaluate the friction factor (f), change in pressure drop (ΔP), outlet temperature (Tout), and thermal performance (ƞ) of base fluid alone (DI Water) and base fluid with nanofluid (Al2O3) flowing in a tube with the insert (twisted tape) with holes of different pitch ratio(Y=6, Y=4), at fixed heat flux value in laminar and turbulent flow condition. The introduction of different pitch ratio(Y=6, Y=4) in modified tube with nanofluids to additionally improve the heat transfer and outlet temperature of the working fluid is a new technique. For Laminar flow condition with DI water as fluid & twisted tape insert of Y=6 & Y=4, the increase in average outlet temperature & Pressure drop is 4.06 %, 0.7 % and 0.07 N/m2, 0.11 N/m2, however for Al2O3 nanofluid & with twisted tape insert of Y=6 & Y=4 the increase in average outlet temperature & Pressure drop is 9.01 %, 8.4 % and 0.10 N/m2, 0.11 N/m2. Similarly for turbulent flow conditions with DI water as fluid & twisted tape insert of Y=6 & Y=4, the increase in average outlet temperature & Pressure drop is 2.3 %, 2.1 % and 3.9 N/m2, 4.6 N/m2, however for Al2O3 nanofluid & with twisted tape insert of Y=6 & Y=4 the increase in average outlet temperature & Pressure drop is 4.8 %, 8.6 % and 5.3 N/m2, 6.3 N/m2

Aluminium 6063 alloy is widely utilized as a structural membrane among automobile and aircraft sectors because of its excellent specific strength and formability characteristics. Aluminium alloys which have been employed in the form of aerospace structural components will undergo dynamic loading which leads to the fatigue which is due to mechanical stress and thermal conditions. Considering studies toward the low cycle fatigue behavior of aluminium alloys are particularly narrowed, this investigation sighted to the analysis of fatigue behavior of Al 6063 alloy at the various strain amplitude of 0.4% and 0.8% which performed through the low cycle fatigue testing machine at the frequency rate of 0.2 Hz. The test reveals that for the higher magnitude of 0.8% strain amplitude the fatigue life was shorter as 291 cycles. Mean Stress of the Al6063 samples relies on the crack initiation and value of the mean stress is a vital parameter for determining the fatigue limits. For 0.4% strain amplitude, it took 1735 cycles to fail but there was only cyclic softening has happened, whereas for 0.8% despite the shorter life. (C) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International conference on Materials and Manufacturing Methods.