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LED technology improved its efficacy through its innovative structures and development. General lighting and automobile industries are rapidly shifting from halogen lamps to LED lamps. LED is popular due to its high lumen output and efficiency which is considered a significant advantage. LED produces localized heat at its junction which directly affects its maximum lumen output range and even leads to failure. The conventional method for LED thermal management involves passive cooling using heat sinks and coolant fluid. The present work emphasizes active cooling of LED array considering various real- time parameters such as junction temperature, ambient and heat sink temperature. The LED experiences active cooling with the help of the feedback system loop controlling the junction temperature by varying the fan speed based on the heat sink temperature sensor output.

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 fabrication or repairing of aircraft components made of Hastelloy X to be resolved using an arc welding technique. In this study, Hastelloy X was joint with ERNiCrCoMo-1 filler by pulsed current gas tungsten arc (PCGTA) welding. The high temperature tensile property of the weldment has been evaluated at three different temperatures such as 700 °C, 800 °C and 900 °C. The tensile properties such as yield strength (294, 259 and 205 MPa), ultimate tensile strength (475, 396 and 245 MPa) and percentage of elongation or ductility (17, 14 and 11 %) follows the similar trend with temperature at 700 °C, 800 °C and 900 °C respectively. It revealed the values of all the properties are decreased as the temperature increased. The lowest strength was evaluated for weldment at 900 °C. The high temperature tensile test also revealed that the fracture of weldments for all three conditions is found at the weld centre (WC).

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).

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.

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).

Aluminum-based metal matrix composites are continuously changing to meet the industry’s specialized needs. In the aluminum alloy series, the AA5052 had a lightweight, high strength, good weldability, excellent corrosion resistance, and a good surface finish during the machining operation. The present work is to improve the mechanical characterization of AA5052 by adding 1 and 2 wt % of Aluminium Titanate (Al2TiO5) reinforcement particles through a stir casting process. The influences of Al2TiO5 reinforcement particle’s microstructural analysis were investigated. The tensile, impact and hardness of the AA5052/ Al2TiO5 composites were also determined by Universal Testing Machine (UTM), Charpy, and Vickers microhardness tester, respectively. The AA5052/ 2%- Al2TiO5 composite microstructure shows a uniform grain distribution. The increased wt 2 % of reinforced particles to AA5052 resulted in an improved microhardness (73.4 HV) and tensile strength (210.28 Mpa).