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Dissimilar metal welds (DMWs), between austenitic stainless steel (ASS) and micro alloyed high strength low alloy steel (HSLA), are used in high temperature applications in power stations and petrochemical plants. The gas metal arc welding (GMAW) has surpassed the shielded metal arc welding (SMAW) process due to its advantages of producing fast, long, clean continuous weld at any position [1, 2, 3, 4, 5]. A studies on mechanical and metallurgical properties of conventional V-groove SMAW and GMA Welding of dissimilar 20 mm thick 304LN ASS and micro alloyed HSLA steel plate were carried out by using austenitic E308L- 15 electrode with gas tungsten arc welding (GTAW) root pass. The tensile (axial and all-weld) properties, hardness and microstructure of the weld and HAZ are analyzed.

The objective of the study is to investigate the effect of current pulsation frequency on the weld bead microstructure, segregation and hardness of Hastelloy C-2000 weldments. Bead on Plate (BoP) welds were made by using Pulsed Current Gas Tungsten Arc Welding method (PCGTAW) at eleven different frequencies. The weld bead width and depth of penetration was measured with the help of Dinolite macro analyzer. The microstructure of weldments are further examined through optical microscope and Scanning Electron Microscopy (SEM) to identify the type of grain, grain coarsening and extent of the Heat Affected Zone (HAZ). The grain structure turn into finer and equiaxed in all cases and there was an optimum frequency range over which the significant grain refinement was observed. Microsegregation of alloying elements were computed with the aid of Energy Dispersive X-ray Spectroscopy (EDS). Vickers Hardness Tester was used to measure the hardness of the weld samples at ambient conditions.

The use of natural fibers composite matrix is tremendously increasing day to day and acting as a replacement product to many conventional materials in the automobile and aviation sectors. It was preferred due to its bio-degradability, weight to strength ratio, easy availability, and lightweight. The crisscrossed woven jute and raw-sisal fibers had drawn the superior properties in the advanced developing field of the composite. The main purpose of this project is to evaluate the mechanical properties and the influence of raw sisal fiber with woven Jute/Epoxy composite by varying the size of raw sisal in three variable lengths such as 10mm, 20mm, and 30mm respectively. The composite laminates were fabricated by the conventional hand-layer technique. The mechanical characterization like the tensile test, flexural test, and hardness, was estimated on the fabricated jute/sisal hybrid composite material.

In this developing world, the need for lightweight and high strength materials is increasing in various industries. As a result of the above, the importance of natural fiber is also increasing to satisfy the industrial need. In manufacturing industries in order to assembly the engineering components the drilling is one of the important operations. The main objective of this research is to determine the mechanical properties and drilling efficiency of natural fiber composite. Sisal/flax as a natural fiber, the copper foil of thickness 0.025mm as structural reinforcement and epoxy resin as a matrix was used for making composite. The hand layup technique was used for the fabrication of the composite. Two different types of the composite were fabricated such as C1 (Sisal and flax fiber, embedded with punched copper foil (Ø5mm), 20mm apart and 90° to each other) and C2 (Sisal and flax fiber embedded with a punched copper foil of (Ø4mm), 20mm apart and 45° to each other).

Natural fibers are one of the major ways to improve environmental pollution. In this study experimental investigation and simulation of honeycomb filled with cotton fabric, wood dust and polyurethane were carried out. This study determines the potential use of cotton fabric, wood dust as good sound absorbers. Automotive industries are looking forward to materials that have good acoustic properties, lightweight, strong and economical. This study provides a better understanding of sound-absorbing material with other mechanical properties. With simulation and experimental results, validation of works provides a wider industrial application for the interior of automotive industries including marine, aviation, railway industry and many more.

This study examines the influence of cryogenic treatment on the microstructure and on the physical properties of the rapid prototype SLS material. The wear properties of the rapid prototype SLS material both before and after cryogenic treatment are studied in three phases. Phase I deals with the sample preparation through the SLS technique; Phase II involves the preliminary tests like roughness test, hardness test, SEM and wear test. Phase III is the cryogenic treatment of the sample in the setup designed. The cryogenic coolant used is Nitrogen, having a boiling point of 77 K, and the whole treatment process takes about 2 to 3 days. Phase IV deals with the testing of the cryogenically treated samples in which similar tests to that in Phase I are carried out. These results are tabulated and graphs are plotted. Furthermore, the percentage change in the hardness and wear properties of the samples are found.

In the last decade, there was growing interest in the use of green composites because of their environment-friendly nature, improvement in mechanical & chemical properties, better processability, and low cost. In this work, short sisal fiber was reinforced in a polycaprolactone (PCL) matrix and four different degradable green composites were developed with different weight fractions. Experimental studies were conducted as per standard to find the mechanical properties of PCL based composites. The data obtained shows that there is a 22% increase in tensile strength, 18% increase in hardness and 100% increase in impact strength for the specimen with 10% sisal fiber compared to neat PCL specimen. The mechanical property reduces when the fiber content is increased to 15%. These PCL based composites shall find applications in the packaging industry and consumer goods that have less service temperature.

The utilization of Additive Manufacturing (AM) technology in the current manufacturing sector is growing day - by - day. This is made possible by the constant development of new materials and techniques to overcome the difficulties that are encountered while fabricating a part. In AM, parts are fabricated by laying successive layers on one another till the complete part is build. This gives AM an edge over conventional manufacturing. Even intricate or hollow parts can be fabricated with the same ease as fabricating a solid part. The key objective of this project is to evaluate and compare mechanical properties of Polyethylene Terephthalate - Glycol modified (PETG) and Carbon fiber reinforced Polyethylene Terephthalate - Glycol modified (CF - PETG), which are fabricated using Fused Deposition Modelling (FDM) process of AM. The ASTM standards D638 and D790 were followed for fabricating tensile test and Flexural test specimens respectively.

The developed model analysis is built in matrix runs to optimise the friction stir welding parameters of rotational speed, welding speed, shoulder diameter and tilt angle in this research. The aim of any design is to maximise the welded properties, either to surpass the base metal properties. The model that is created is the product of a number of regression methods that have been tested for adequacy. In this model we have taken three levels of varying parameters shoulder diameters, rotational speed, welding speed. Mathematical model is developed for the effect of three process parameter at three levels using response surface methodology (RSM).

Aluminium metal matrix composite are broadly used in various field like aerospace, marine and automobile application. The application of composites necessitates joining process and its difficult due to different materials. To address the considering difficulties the present study is, Cr2O3 was reinforced in Al 6061 matrix in 2 % to 6 % in the incremental step of 2 %. The stir casting method was used to fabricate the composites with 300 rpm stirring speed and the stirring time duration was 3 min throughout the fabrication process. The H13 tool is used for prepared friction stir welded (FSW) joints and tool having 6.7 mm pin diameter and 6 mm pin height. The fabrication process is conducted by 500 rpm and 700 rpm tool rotational speed with 50 mm/min and 60 mm/min welding speed receptively. The atmospheric environmental condition was preferred to perform friction stir welding.

This work inspects the metallurgical and tensile demeanor of pulsed current gas tungsten arc welded ERNiCrCoMo-1 filler wire on alloy 80A weldment. Defect free weldment was achieved in a four pass through PCGTA welding. The center of the weld microstructure is decorated with equiaxed dendritic structure and columnar dendritic structure. SEM analysis showed the existence of Mo, Fe and Ti secondary phase precipitation in the grain boundary region of the weld zone. Tensile testing was conducted to analysis the strength and ductility of weldment. The result showed that the tensile strength and ductility were lower than that of base metal (BM).

Fiber-reinforced polymer composites propose exceptional directional mechanical properties, and combining their advantages with the potential of 3D printing has resulted in many novel research fronts. Industries have started using 3D printed components which are rapidly replacing conventional material components in most of the industries. Carbon fiber reinforced Polylactic Acid (PLA) often finds its application in reasonably high loading conditions working at lesser speed like lightweight gears, spanners, nuts, and bolts. Wear reduction is an important factor that plays an important role in prolonging the component's life. Hence, it is crucial to optimize 3D printing parameters to get desired strength according to the application. The aim of this paper is to conduct the wear rate test on the Fused Deposition Modelled (FDM) printed carbon fiber reinforced PLA parts, to identify the optimum printing parameters which are crucial for wear reduction.

The current research work scrutinized the influence of plasma arc in the metallurgical and mechanical behavior of Nimonic 80A weldment. Defect free weld bead of 6 mm thickness was achieved in a single pass through plasma arc welding. The microstructure of weldment is decorated with cellular dendritic structure at the center and at the weld interface region columnar dendritic structure was observed. Metallurgical analysis showed the Cr and Ti secondary precipitates in the interdendritic region of the WZ. The existence of M23C6 and Cr2Ti were observed through the X-ray diffraction analysis. Both tensile test and microhardness test were conducted to study the mechanical properties of weldment. The result concluded that both the strength and ductility inferior than base metal and the hardness of the weld bead is similar to that of BMl.

The ground mobile robotics study is structured on the two pivotal members namely Sensor Perception and Motion Planning. Sensor perception or Exteroception comprises the ability of measurement of the layout of the environment relative to vehicle's frame of reference which is a necessity for the implementation of safe navigation towards the goal destination in an unstructured environment. Environment scanning has played a significant role in mobile robots application to investigate the unexplored environment in the sector of defence while transporting and handling material in warehouse and hospitals. Motion Planning is a conjunction of analyzing the sensor's information while being able to plan the route from starting point to the target destination. In this paper, a 3600 2-D LiDAR is used to capture the spatial information of the surrounding, the scanning results are presented in a local map and global map.

Collection of various data from sensed data or raw availability of data from transcript or interdependency of data from various sources is a tedious task in a real time scenario like an Indian context is considered. Planning to find a solution to collect the data from various vehicular devices about the information related to the pollution becomes a cumbersome job. The need of the data, under what time duration data has to be transmitted, how they are interconnected and whether data needs to be stored or how they are processed is a major question that arise when dealing with collecting data and internetworking with various vehicular devices. A study of two different types of approaches for internetworking between the devices is discussed. One related to real time setup of mobile application and other with the dynamic cluster approach when the nodes are moving in a region was considered.

The present research investigates the corrosion behavior of aluminum metal matrix composites (AMMCs) in NaCl solution. The test was designed and performed based on Taguchi’s L8 orthogonal array. The stir casting technique fabricates the AMMCs, and silicon carbide (SiC) is individually reinforced in Al 6061 and Al 5052 matrix. The SiC particle are reinforced in a matrix with 5% and 10% separately in Al 6061 and Al 5052. The test variables used during corrosion studies were reinforced Al matrix, wt% of SiC, molar solution, and corrosion duration for stir-casted composite samples. The Al 6061 and Al 5052 composites were tested in 1M and 2M molar NaCl solutions for 15 and 30 days exposure duration. According to ASTM G31, the solution immersion tests were carried out. The corrosion surfaces are examined by optical microscope and field emission scanning electron microscopy (FESEM) equipment. Through microstructure, it is noted that the corrosion concentration is along the grain boundaries.

Turning is a widely used manufacturing process in mechanical machining industries, while the cost associated with this process is high due to the cost involved in changing tools or tool regrinding. All the parameters of turning, like feed rate, cutting speed, and depth of cut, substantially impact the tool wear, which subsequently reduces tool life. Cooling methods like flooding, Minimum Quantity Lubrication (MQL), etc., are incorporated to minimise these effects on the tool and workpiece interface. When using these cooling techniques, the process parameters involved play vital roles in increasing the effectiveness. This paper focuses on the effects of machining parameters on the tool and the workpiece quality. Experiments were conducted to study the impact of various input parameters of the turning process on the tool tip temperature, cutting forces, and tool wear, ultimately affecting the tool's life.

The present paper mainly focuses on the analysis and multi-factor optimization of cutting process parameters in turning Hastelloy C-276 using an integrated approach of Weighted Aggregated Sum Product Assessment (WASPAS) and criteria importance through inter-criteria correlation (CRITIC). To achieve this objective, a design of experiment (DoE) is employed for the three control parameters: cutting speed, feed rate, and cutting depth. The insert used for turning is a coated carbide insert (PVD: Ti-Al-N). Different responses are recorded: force, tool wear, and surface roughness in machining attributes, chip structure, chip thickness, chip thickness ration, shear angle, and friction coefficient in chip-tool interface indices. Uncertainty probabilistic study depends on Monte Carlo (MC) method applied.

The increased use of electronic systems has become a severe concern for electromagnetic pollution, leading to the development of materials to reduce electromagnetic interference (EMI). The present study investigated the EMI-shielding effectiveness (EMI-SE) of flax fiber polymer composite (FFC) in the available free space method by varying the wt.% of Rice husk ash (RHA) and hematite. The flax fiber was coated with the dip coating technique, and the coated fibers were used for preparing FFC by hand layup. The EMI-SE was measured at 32-33.5 dB in the X-band frequency range (8-12 GHz). As the cost is low and can be mass-produced, results show that the developed FFC are suitable for electric vehicle applications specifically to shield Electronic control units (ECU), where the interference effect needs to be reduced.

The research aims to optimize the surface roughness, material removal rate (MRR), tool wear, and spark gap for input machining parameters such as Pulse on-off time and wire feed rate. The experiment results of WEDM of Duplex stainless steel are optimized by ANOVA and Response surface methodology (RSM) approach. Taguchi’s orthogonal array L9 (3*3) was used to design the test condition for the experiment. After the model validation, ANOVA was used to identify the most significant input factor on the output. Response surface methodology was used to find the ideal cutting conditions which produce the best-desired output in terms of less tool wear, lower surface roughness, lower spark gap, and higher material removal rate. The optimal MRR, Spark Gap, surface roughness, and tool wear parameters for Duplex Stainless Steel are obtained at Pulse on 110.23, Pulse off time of 56.0, and a wire feed rate of 1.0.