This paper focused on the sensitization behavior of cryo-rolled standard duplex stainless steel (DSS) 2205. Solution-annealed DSS specimens were cryo-rolled and achieved reduction in thickness percentage range from 0 to 45

As is the case in most countries around the world, India is witnessing a rapid growth in the automotive industry. However, the current infrastructure will not be able to accommodate the growing number of vehicles on road. In many instances, large spaces aren’t utilised to their extent particularly because of no proper signs or markings on road, improper management of space by authority. Hence, in order to continue to sustain the growth of industry and accommodate vehicles in cities, steps must be taken to utilise and manage space effectively. This can happen if we systemize the process of parking on roads or in any large space. Taking this into consideration, a system is proposed to systemize the process of parking for passenger vehicles and also guiding the drivers during parking. Moreover, the system will help the authorities to determine traffic hours, availability of parking space and their demand based on the data that the system will help generate. The proposed system principle can also be extended in hilly areas with narrow roads. A system when setup in such region will help the drivers know their tyre position aiding in parking and also help in utilising maximum road thereby preventing road congestion.

Generative design is growing in prominence across various engineering fields owing to the increased sophistication and convenience it provides to the design engineers, researchers and students. This work involves applying generative design feature during the initial stages of brake design to come up with an ideal design for a brake disc that precisely meets only the required criteria thereby saving material, cost and time. Brake disc is a critical part of the braking system and is used to produce friction large enough to stop the vehicle. But they are heavy. Reducing the weight will increase life of brake parts and lower inertia since brake is an un-sprung mass. This research is carried out with an aim to reduce the mass of brake discs while maintaining stiffness enough to withstand the braking forces acting due to the calliper and also the resultant friction produced by it. The frictional force produced during the braking action is converted into heat energy. This heat energy increases the temperature of the brake disc. Extreme high temperatures can cause brake fading problems which will lead to the disc being non-functional. Ideally; excellent heat dissipation is required to so that the heat produced never exceeds the thermal storage capacity of the brake disc material. This is commonly done by increasing surface area and providing proper air ventilation channels. Drilled holes, slots are made in the disc to increase the flow of air which helps in reducing and maintaining temperature. The average weight of brake disc used in automobiles are normally more than 5kg. Our aim is to reduce the weight under 2kg using generative design. Therefore, the challenge is to meet the requirements of mechanical performance while trying to reduce mass of the brake disc. The new results are compared with the conventional designs already available. The research further helps realise the existing limitations of generative design technology and its scope for becoming the primary method for design optimization process.

Metal casting plays a vital role in manufacturing industries. The properties of molding sand and process parameters (melting temperature, pouring temperature and moisture content) determine the quality of the casting. Hence on-line monitoring of such parameters for its fluctuations is needed for efficient monitoring and to take corrective action to increase the efficiency of the system. In this paper, the framework of Internet-of-Things (IoT) paradigm based smart devices were used for continuous monitoring of temperature, moisture. The successful implementation of IoT framework ensured possible optimization strategy of energy-related data and feasibility of the developed IoT system for foundry industries. Further, the general-purpose programming language such as C++, JavaScript (JS) and standard markup language such as hypertext markup language (HTML) was used for successful implementation of IoT system. The first attempt, towards optimizing of energy is to control the power/energy consumption, majorly in metal casting industry is the furnace. Further, these results can be sent to user defined set of mobile devices.

The passive film mainly consists of oxides and hydroxide and is a key for corrosion protection of metallic materials. It increases the durability and performance of engineering components by spontaneous formation of effective, adherent barrier between the corrosive environment and a substrate. Herein, influence of plastic strain and after heat treatment on austenitic stainless steels was compared with the focus on stability of the passive film. The following materials were used in this study: Sanicro 28™, AISI 316 L, and AISI 304 L. These specimens were subjected to a true strain of 0.58. The conventional three-electrode cell was used to record the anodic potentiodynamic polarization curves. The grain size and other misorientation parameters were extracted using electron backscattered diffraction (EBSD). Fourier transform infrared spectroscopy (FTIR)-imaging was used for capturing chromium oxide (Cr2O3) peaks for all specimens. The average area of Cr2O3 peaks was compared with deformed and after heat treatment of 700 °C 30 min specimens. It was found that heat-treated specimens exhibited slightly higher average area of Cr2O3 than deformed.

The specimens of austenitic stainless steels were machined to different strain rates (105 s−1, 1050 s−1, 1500 s−1, 2100 s−1). These specimens were subjected to low-temperature sensitization (LTS) heat treatment. The LTS treatment was carried out at 475℃ and 575℃ for 24 h. Further, oxalic acid, double-loop electrochemical potentiokinetic reactivation (DL-EPR) were carried out. As-machined specimens were subjected to surface roughness measurements, optical microscopy, electron backscattered diffraction (EBSD), and Fourier transform infrared spectroscopy (FTIR) imaging measurements. Machined specimen exhibited more difficulty in passivation than the as-received specimen. The complete surface statistics were extracted. The specimens machined at a strain rate of 2100 s−1 were exhibited a higher degree of sensitization (DoS) at LTS of 575℃ and 475℃ for 24 h, respectively, than other specimens. It was found that specimens machined at a higher strain rate produced smoother roughness. FTIR imaging was used to extract the signal intensity of chromium oxide (Cr2O3) peak. Detected Cr2O3 peak/signal was strong for the specimen that exhibited lower DoS as estimated from FTIR-imaging.

In this manuscript, the latest developments pertaining to sensitization are discussed. Sensitization leads to intergranular corrosion and intergranular stress corrosion cracking. The advantages and disadvantages of conventional methods to combat sensitization are elaborated. Emerging/newer techniques such as grain boundary engineering, creation of orientation gradients, and high density of twinning to improve resistance to sensitization are also covered. Detection and monitoring of deleterious phase precipitation such as carbides, nitrides, and other intermetallic phases during operation necessitate making use of nondestructive testing (NDT) methods. Possible information that we get from NDT is for material characterization includes the size, shape, and location of a defect. Herein, the significant developments for monitoring and detection of phases concerning sensitization by NDT are discussed. These range from magnetic methods to ultrasonic techniques. The multi-physics approach is essential to fully utilize NDT to ensure/predict the lifetime of the components used in the industry. Further, proper selection of suitable NDT for defect detection can avert accidents, catastrophic failures, and economic losses due to corrosion degradation. For this, the corrosion engineer/corrosionist properly apply the suitable techniques (prevention, monitoring, and assessment) to address the issues of sensitization among the wide choice available.

The friction welding of tube to tube plate using an external tool (FWTPET) is widely deployed in several industrial applications, such as aerospace, automotive, and power plants. Moreover, for achieving a better tensile strength and hardness in the weld zone, the friction stir processing (FSP) technique was incorporated into the FWTPET process for joining aluminum alloys (AA6063 tube, AA6061 tube plate). Furthermore, it has to be noted that FWTPET was applied for joining the AA6063 tube to the AA6061 tube plate, and FSP was deployed for reinforcing the weld zone with carbon nanotube (CNT) and silicon nitride (Si3N4) particles, thereby attaining the desirable mechanical properties. Subsequently, the Taguchi L25 orthogonal array was used for identifying the most influential input and output FWTPET + FSP process parameters. Furthermore, particle swarm optimization (PSO) and the firefly algorithm (FFA) were deployed for determining the optimized input and output FWTPET + FSP process parameters. The input process parameters include CNT, Si3N4, rotational tool speed, and depth. Furthermore, the tensile strength of the welded joint was considered as the output process parameter. The process parameters predicted by PSO and FFA were compared with the experimental values. It was witnessed that deviation between the predicted and experimental values was minimal. Moreover, it was found that FFA provided a superior tensile strength prediction than PSO.

A novel phenomenon known as Industry X.0 is becoming extremely popular for digitizing and reinventing business organizations through the adaption of rapid and dynamic technological, innovational, and organizational changes for attaining the profitable revenue. This work investigates the die-casted commercially pure aluminum alloyed with 9% silicon and 3% copper (AlSi9Cu3) that is produced through the gravity die casting process. Further, the degradation of surface coating on die-casted AlSi9Cu3 alloy was explored. The acrylic paint electrodeposition (ED) coat, 2-coat polyester without primer and 3-coat polyester with epoxy primer powder coatings were used in this study. Moreover, the 3.5 wt.% of sodium chloride (3.5 wt.% of NaCl) test solution was used for electrochemical and salt spray test and the tools used to assess electrochemical properties were electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and neutral salt spray test (NSS). The microstructure of AlSi9Cu3 after corrosion exposure was investigated; also, the microstructure of coated and uncoated AlSi9Cu3 samples was analyzed by SEM microscopy after corrosion exposure. Besides, the electrochemical studies were also carried out on the Al alloy die casting. It was found that acrylic paint ED coatings exhibited higher corrosion resistance than 2-coat polyester without primer & 3-coat polyester with epoxy primer powder coatings. Acrylic paint ED coating showed higher corrosion resistance in AC and a lower value in DC and 3-coat polyester with epoxy primer powder coating displayed higher corrosion resistance in DC and a lower value in AC.

The use of UAVs has been on the rise since the past decade. These UAVs are very versatile and can be applied to several fields ranging from agriculture to military reconnaissance. Due to the immense functionality of the UAVs, it has now become a very popular topic in Research. With the advent of Deep Learning and Machine Learning the autonomous navigation functionalities have been improved but it still poses a challenge as navigating a drone involves the integration of its software and hardware functionalities. This paper reviews both indoor and outdoor navigation. Topics in navigation such as Control, Hardware, Algorithms, Path-Planning, and communication are touched upon in this paper. The paper also presents a discussion on the Navigation of UAVs using visionbased technologies, this technology encompasses the use of various sensors and cameras and integrate it with the navigation system of the UAV to ensure the success of UAV’s operation. UAVs play a pivotal role in networking, many applications have been developed which have UAVs as an important component in them. Their applications include Urban computing, Internet of Things, Ubiquitous Computing to name a few. Safely operating a UAV as a network node is not a simple task, these nodes are prone to various types of attacks. A new type of attack introduced in this paper is termed as “Coagulation Attack”. This attack gets its name from the coagulation property of fluids wherein fluids clot and their particles settle down. This paper explores the concept, issues, challenges and research aspects of Coagulation attack. This paper also introduces the concept of Underwater Wireless Communication. On a planet where 70% of the surface is covered in water, UWC has a lot of potentials to be exploited. Moreover UWC is critical in many key areas of Maritime research, commerce, and surveillance. UWC is used for experimental observation, data collection and analysis, underwater navigation, disaster prevention and early detection warning of a tsunami. In addition, we summarize emerging technologies in the UWC, future research directions and recommendations using fifth-generation (5G) communication techniques.

The anodic potentiodynamic polarization behavior of various grades of cold-worked (rolling and machining) austenitic stainless steels were studied. Deformed specimens were characterized by Electron backscattered diffraction (EBSD) and Fourier transform infrared spectroscopy (FTIR)-imaging. The FTIR-imaging was used to quantify chromium oxide (Cr2O3) spectra. It was observed, average area under Cr2O3 spectra was decreased with increase in cold -working. The certain regions in deformed microstructure showed higher value of area under Cr2O3 spectra, indicated stability of passivation film that needs to be explored. There was no microstructurally different between machined specimens.

The Environment Assisted Cracking (EAC) of grade P92 was investigated by employing a new testing method. The main aim is to understand the mechanism of the EAC. The specimen was subjected to a static load of approximately 90% of the material's yield strength. The experimental work was carried out under the various corrosive environments such as NaOH, KOH, HCl, CuSO4, and CH4N2S test solutions until it gets fractured, which takes a duration of one week (168 h). These specimens were subjected to the Scanning Electron Microscope (SEM) analysis for obtaining its microstructural characterization. Further, the obtained microstructural images can be utilized to understand the failure mechanism. It can be witnessed that the majority of failures appear in the region around the coarse-grained HAZ. Subsequently, the results indicate that the passive path corrosion mechanism seems to be the preferred one as P92 welds are vulnerable to EAC.

This paper focused on effect of strain on stability of passive film in three different grades of austenitic stainless steels. These were Sanicro 28 (TM), AISI 316 L and AISI 304 L steels. These specimens were subjected to unidirectional cold rolling and achieved true strain was 0.26 and 0.58. Potentiodynamic anodic polarization tests were carried out for all specimens in different test solutions. The changes in anodic polarization parameters were recorded. The deformed microstructures were characterized by using electron backscattered diffraction (EBSD). Aim of this study was to characterize chromium oxide (Cr2O3) by Fourier transform infrared spectroscopy (FTIR)-imaging. Further, an attempt was made to combine EBSD and FTIR-imaging for direct microstructural correlation.

In this study, Friction Welding of Tube to tube-Plate using an External Tool (FWTPET) is carried out by joining SA213 tube and SA387 tube plate alloying materials using an external tungsten tool by close fit methods in absence of backing plate without hole on the circumference of the tube for superior mechanical and metallurgical properties. The optimization techniques such as Taguchi L9 and Analysis of Variance (ANOVA) is used to endorse the capital joint strength. The output parameter (TS) and input factors (tool rotational speed, tube projections, depth of cut) are designated for the study. The heat that produces from tool pin, dissipates to the tube and the tube plate during FWTPET process. The grain size measurement, x-ray diffraction (XRD) phase analysis, radiography test is carried out after FWTPET process. In this research work, FWTPET process is carried without hole on the circumference of the tube, further FWTPET process is also compared by without employing supporting arrangement. Excellent joint strength of 762.2 MPa is achieved with the absence of supporting specimen which without hole on the circumference of tube for the tool rotational speed of 1300rpm. Keywords: Friction welding, FWTPET, Analysis of Variance (ANOVA), Optimization techniques, Tensile strength

In the present study, TC4 titanium alloy was gas tungsten arc welded to evaluate the mechanical and metallurgical properties of the welds. The welds were carried out at different welding conditions such as welding speed and current to identify their effect on microstructural changes and strength of the welds. The results of bead geometry measurements suggests that the fusion zone width and depth was greatly varying with the welding speed and current. It is also observed that the fusion zone microstructure and heat affected zones are greatly controlled by welding conditions. Therefore the mechanical properties of the welds were improved with the changes in welding conditions and are correlated with the metallurgical features of the welds. The optimal welding conditions were analysed using Box-Behnken design and analysis of variance technique for identifying strength of the welds and better bead geometry parameters.

In modern times, the Industry X.0 has emerged as the paradigm that has become the core of digital technology-driven business organizations. Further, this paper establishes a tube to tube plate friction welding technology with the help of deploying an external tool, also known referred to as the FWTPET scheme. Besides, the SA213 tube and SA387 tube plate were combined by employing a unique interference fit technique. Also, the strength of this combined portion was assessed with and without the aid of a holding block. Subsequently, the analytic optimization approaches like genetic algorithm, analysis of variance, and Taguchi L9 orthogonal array design were deployed in the prediction of the optimum joining strength. Moreover, the input parameters include the projection of the tube (mm), the rotational speed of the tool (rpm), and depth of cut (mm); besides, the tensile strength is considered as the output parameter. Also, the grain size distribution around the weld zone and the presence of base metal were measured through an optical microscope as per ASTM linear intercept method. Further, it is evident that grain refinement had occurred in the weld zone, which in turn increases the tensile strength. The exceptional weld strength (tensile strength) was obtained when joining of SA213 tube and SA387 tube plate through interference fit using a holding block without a hole in the tube. Experimentally, it was found that the achieved tensile strengths were 836.8 MPa (without a hole) and 789.35 MPa (with hole) using the holding block, respectively. Additionally, it was found that in the absence of a holding block, the achieved tensile strength is 762.2 MPa (without a hole), and 700.8 MPa (with a hole), correspondingly. The deviation of tensile strength between the predicted (genetic algorithm) and experimental was found minimal. Therefore, for achieving this strength, the suitable operating parameters set include the rotational speed of the tool (1300 rpm), projection of the tube (1 mm), and depth of cut (0.5 mm) with backing block configuration.

This study dealt with characterizing oxide passive films in austenitic stainless steels with different chemical compositions. Stacking fault energy was estimated, and thermal conductivity at different temperatures (298, 673, 873 and 1073K) were calculated. Steels specimens were plane strain compressed and subjected to anodic potentiodynamic polarization scan in a different deaerated testing environment. The deformed specimens were characterized using electron backscattered diffraction system and Fourier transform infrared spectroscopy (FTIR)-imaging. The Cr2O3 peak from FTIR-imaging was captured, and area of the peak was calculated after anodic potentiodynamic polarization scan. The intensity of Cr2O3 peak was related to deformed microstructural features.

This paper focussed on sensitization behaviour of cold rolled (CR) and warm rolled (WR) of AISI 304 L austenitic stainless steels. The main aim of this study was to mitigate sensitization issues of austenitic stainless steels. All the specimens were given two different heat treatment of 675 °C 6 h and 675 °C 5 h. The electron backscattered diffraction (EBSD) measurements were revealed developments of in-grain misorientations and types of grain boundary statistics. An EBSD system along with a suitable computer algorithm was used to quantify in-grain misorientations called near boundary gradient zone (NBGZ). The microstructures that contained quantifiable zones of in-grain misorientations exhibited low value of degree of sensitization (DOS) for 5% and 10% rolled specimens. DOS was assessed by double loop electrochemical potentiokinetic reactivation (DL-EPR) test. It was established that low value of DOS for the specimens of 5% and 10% rolled provided diffusion short-cuts or high diffusivity paths for Chromium that improved resistance to sensitization. A slight pre-strain and subsequent annealing failed to increase population of special boundaries. The visible grain fragmentation accelerated carbide precipitation and decreased resistance to sensitization. The sensitized specimens after DL-EPR test subjected to white light interferometry (WLI) measurements that revealed grain boundary depth information. The combined data set of EBSD + WLI provided linkage between grain boundary depth and in-grain misorientations.

In the present study, aluminum alloy 2219 of two different heat treatment states were selected and welded using the friction stir welding process to evaluate the effect substrate on the joint properties. The microstructural observations have exhibited the difference in their characteristics between two heat treatment conditions of 2219-O and T6 conditions. The tensile strength of the AA2219-T6 joints much higher than the AA2219-O joints. Consequently, the microhardness distribution across the different zones varying with two different heat treated conditions. The failure locations and fracture surface features are revealed the significant differences among these two heat treated conditions with the change in their failure location and the fracture morphologies. The optimal welding conditions were analyzed to determine the high strength of the welds with excellent metallurgical properties of the welds.

Laser beam welding is one of the most favorable welding technique and its importance in industry is demanding due to higher welding speeds and lower dimensions and distortions in the welds. Moreover, its high strength to weld geometries and minimal heat affected zones makes favorable for various industrial applications. In the present study, laser welding of titanium alloy was investigated to observe the effects of parameters on the bead geometry and metallurgical properties. The laser power and welding speeds were varied to identify their impact on the formation of weld geometry. The width and depth of the fusion zone is varied with welding conditions. The finer grains identified in weld zone and the width of heat affected zone was significantly changes with laser welding power. The mechanical properties of the weld joint are controlled by obtaining optimum weld bead geometry and width of the head affected zone in the welds.