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Higher heat input rates and uneven thermal cycles involved in fusion welding processes effect HAZ properties and causes to develop residual stress across fusion zones. These thermal stresses reduce...

The idea of an unintentional self-mending material in which the commencement of fixes is a basic piece of the substance presently being considered for designing purposes. This thought propelled by essentialness empowers the architect to consolidate auxiliary practical materials fit for balancing debasement of administration while as yet satisfying fundamental, normally primary necessities. In nature, most substances are self-mending composites themselves. This paper analyzes various self-mending procedures for fiber-strengthened polymer composites as of now being made, a large portion of which are motivated by science; enlivened naturally perception. The latest self-recuperating examines endeavored to utilize a more exhaustive investigation of common cycles to mirror non-intrusive treatment. A perspective is given on current and potential ways to deal with self-mending. In this energizing region, the point is to invigorate conversation and fortify the significance of a multidisciplinary approach.

In the present paper, similar and dissimilar combinations of AA 5052 and AA 6061 Aluminum grades were joined using FSW to obtain desirable mechanical properties. Modified HSS tool containing 10% cobalt with taper pins of circular and trapezoidal cross sections are developed to obtain FSW sheet joints. Process parameters are selected same for both the pin profiles for obtaining weld joints of similar and dissimilar combinations. Welds were obtained at tool rpm of 1600 and 2600 with feed of 15 mm/min. and 20 mm/min. Tensile and hardness properties of AA 5082 and AA 6061 weld joints were analyzed by tensile test and hardness test respectively. It was observed that the taper pin with square tip has produced better mechanical properties in similar and dissimilar weld joints.

Gas Tungsten Arc Welding (GTAW) has been extensively in use over a period in mechanical industry. Most of the problems associated with the structural development involving Aluminium is still a challenging and requires a methodological study to understand weldability of dissimilar Aluminium base materials. In this present study, mechanical and metallurgical properties of AA 2025, AA 5083 and AA 7075 weld joints made with GTAW have been presented. Mean pulse current of 80 A to 100 A was selected to join the similar and dissimilar base material combinations to make comparative studies. Difficult to weld base material combinations, AA 2027 with other selected base materials, and with non-heat treatable base materials were subjected to post weld heat treatment. Tensile and hardness tests were performed to evaluate the properties of as weld and post heated dissimilar weld joints.

In this paper, the weld joints of AA5052 and AA6061 were developed by using gas tungsten arc welding process with ER4043 filler. The process parameters such as welding current and root gap were considered and ultimate tensile strength, hardness and impact toughness were considered as output factors. Full-factorial method was employed to design the experiments. Regression models were developed for each output responses by using linear fit approach. Further, analysis of variance was performed to study to effect of individual parameters on output responses. Higher tensile strength of 393 MPa and impact strength of 59 J were observed when welding current is at 210 A and root gap at 1 mm. The welding current and root gap are the main effecting parameters for this dissimilar welded joints.

Dissimilar weldments of Monel 400 and UNS S32750 are widely used in pressure vessels and marine industries where the weldments are exposed hot corrosion and can withstand this effect as they offer excellent corrosion resistance and improve the service life. This research paper aims at investigation on the weldability and welding strength of dissimilar welded joints of UNS S32750 and Monel 400 developed by pulsed current gas tungsten arc welding technique. ERNiCrMo-4, ERNiCrMo-3 and ER309L fillers were used to join the base metals. Mechanical properties were demonstrated by using tensile test, impact toughness test and microhardness. The ultimate strength of ERNiCrMo-4 weldment was increased by 16.2% and 20.2% when compared to ERNiCrMo-3 and ER309L weldments, respectively. The fracture has occurred under direct tension test in all the cases at the base metal of Monel 400. The superior impact toughness value (169 J) was observed in ERNiCrMo-4 filler weldment than the ERNiCrMo-3 (144 J) and ER309L (76 J) filler weldments. The average hardness number of ERNiCrMo-4 filler weldment (318 HV0.1) was higher than those of ERNiCrMo-3 (306 HV0.1) and ER309L (286 HV0.1) filler weldments.

Study of the weldability and mechanical behavior of bimetallic welds of AA5052 and AA7075 obtained from gas tungsten arc welding process was done. Two filler wires viz., ER4043 and ER5356 were employed to join the dissimilar metals. The process parameters and welding conditions were used same in both filler weldments. Non-destructive testing was carried out to confirm the weldability of dissimilar joint with fusion welding process. The mechanical tests such as tension, hardness and impact test were conducted as per ASTM standards to evaluate the weld properties. Weldments obtained using ER4043 filler has exhibited superior quality with UTS of 182 MPa. It was found that the welds of ER 4043 have shown higher impact strength of 62 J whereas weldment obtained by ER 5356 has given toughness value of 24 J. The micro-porous and voids were observed in weld zone when ER5356 filler was employed.

This research manuscript compares the metallurgical changes and mechanical behavior of AISI 316 and Monel 400 dissimilar weldments developed by Interpulse TIG welding process with ERNiCrMo-3 and ER316 filler wires. Metallurgical aspects are envisioned by using optical and scanning electron microscopes. Mechanical behavior of welded joints were studied by conducting tensile and microhardness tests. Metallurgical study has shown that the ERNiCrMo-3 filler weldment divulged completely with austenitic phase structure at the weld zone. Also, at the HAZ of Monel 400 clear grain boundaries with fine grains were observed. The mechanical properties corroborated that the weld strength of ERNiCrMo-3 weldment was found better than the ER316 weldment. Microhardness on the weldment made of ERNiCrMo-3 filler has shown higher values than that of base metals. Weldment made by ER316 was observed to fail near the interface of Monel 400 under tensile test due to the existence of micro-pores and partially melted zones. Further, the metallurgical and mechanical properties are compared with that of the weldment developed by TIG welding process.

The chromel was one type of nickel-based metal matrix (MMC) and it was fabricated through stir casting technique. The titanium carbide (TiC) was used as a reinforcement material. The particles were analyzed through Atomic Force Microscopy (AFM) and Dynamic Light Scattering (DLS). Abrasive Water Jet Drilling (AWJD) was mechanical energy based non-traditional process that was applied to pierce the stir casted chromel MMC. During the drilling process, jet pressure, traverse speed, and standoff distance were pointed as the main input factors. The Material Subtraction Rate (MSR) and Surface Finish (SF) have been chosen as the response factors. The effect of factors and their correlation were validated through variance test and interface plots.

A comprehensive numerical study is undertaken to analyze the responses of nanoindentation on Ti-6Al-4V alloy using finite element approach. Indentation depth, coefficient of friction, and indenter size were investigated to characterize the Ti-6Al-4V alloy via load Vs displacement curve. The degree of pile-up and sink-in behavior of the material also discussed as well.

The paper work describes the pultrusion process and also selection of die raw material which is suitable for the production of constant cross-section composites of any desired length. It is a manufacturing process for producing various cross-section products in a mass production. As the product quality is purely depending upon the mold, such as the parameters of mold design, material of construction, mold length, hold down hole size & location, heat zones. And the process parameters like heating rate, pulling speed and the curing kinetics of resin system influent the mold quality. Die length, width & thickness of design will be standardized, based on the design die fabrication is done with the help of the Computer Numerical Control (CNC) machine, by using this P20 & EN8 dies, production was taken out and done experimental test on end product, based on the experimental & numerical test results and also finishing & quality. Comparing the two end product based on the result and quality of product taken from the P20 & EN8 dies, by the end of this composites production which was taken from the P20 die have best results, finishing & quality compare to EN8.

An experimental investigation was made to analyze the residual stress distribution in the dissimilar TIG weldments of AISI 304 and Monel 400. Finite element model has been developed to predict the temperature fields and residual stress distribution in weldments. A coupled sequentially thermo-mechanical transient analysis was used to carry out with ANSYS 16.0. The temperature dependent properties of base metals are considered during the welding modeling. The heat flow rate during the welding due to conduction, convection and radiation was considered. The predicted residual stresses are validated experimentally by employing XRD Technique. The residual stresses developed in weldments are within the yield limits.

The correct selection of manufacturing conditions is one of the most important aspects to take into consideration in most manufacturing processes and, particularly, in processes related to electrical discharge machining (EDM). It is a capable of machining geometrically complex or hard material components that are precise and difficult-to-machine such as heat-treated tool steels, composites, super alloys, ceramics, carbides, heat resistant steels, etc. being widely used in die and mold making industries, aerospace, aeronautics, and nuclear industries. This chapter highlights the programming for machining in electrical discharge machine.

Silicon metal matrix composites are extensively used in many industries such as automobile, aerospace, marine and mineral processing industries due to their enhanced wear properties. This experimental investigation deals with tribological behaviour and electric discharge drilling (EDD) of the silicon metal matrix. The duplex silicon metal matrix is synthesized by stir casting process and characterization was studied through a scanning electron microscope (SEM) and energy dispersive analysis of X-rays (EDAX), respectively. Mechanical properties such as hardness, tensile strength and impact strength were estimated after adding the weight percentage of titanium carbide. Drilling holes were formed on the surface of the metal matrix using electric discharge machining (EDM). Wear characteristics are carried out by pin on disc apparatus. Applied load, sliding velocity and weight percentage of reinforcement were considered as the input parameters. Wear rate is the response parameter for this experiment. After wear test, morphology of the worn out surfaces was analysed by SEM. It was clearly observed that mechanical and wear resistance were improved by increasing the weight percentage of reinforcement material. The influential parameter and its effect have been found out by analysis of variance (ANOVA).

The present world demands variety in products and it is not possible with special purpose machines in mass production. To meet the demand for high product variations the industry is working with small batches. Flexible automation can support the situation to meet the expectations with the advancements in CNC technology. The recent developments in the field of CNC technology have shown its capability to produce complex shapes at ease than earlier. The multiaxis machines are highly included in production processes due to their flexibility and suitability for different control and processing units. The difficulties and common errors that will happen with multiaxis CNC machines are discussed.

In recent days, the requirement of advanced materials plays an important role in the engineering field. Simultaneously, material properties have been fulfilled the demand for industrial applications. Advanced new materials are to be achieved through one or more materials combined with each other. Composite materials have been satisfied all kinds of applications. Due to their excellent properties, they are used in various fields such as aerospace, automobile, medical, communication, electrical and electronics fields. Titanium–graphite metal matrix provides excellent properties such as strength, hardness, corrosion resistance, thermal and electrical conductivities. Titanium–graphite composite samples with the volume fraction of graphite in the mixture are 3, 5 and 10% prepared by spark plasma sintering (SPS) process. It has been observed that addition of graphite into titanium provides higher amount of density and hardness. Metal matrix characterization has been studied through scanning electron microscope (SEM) and X-ray diffraction (XRD). Titanium–graphite composite has been machined by electrical discharge machining (EDM) process.

Laser beam welding is a non-traditional, advanced technique used for similar & dissimilar materials and is widely used in various industries like automobile, aerospace, nuclear reactors, etc. at a faster pace. As it is a complex process, it is very difficult to find the optimal process parameters. The primary point of welding is to acquire a high quality joints and requiring little to no effort. However, without optimization, it is impractical to accomplish minimal effort welding. The principle work of this exploration is to display, break down and improve weld bead geometry in the powerful ND: YAG laser butt welding of Inconel 625. However, in view of the literature review, the responses are continuous and have impact on the welding geometry. In this way the feasible varieties of the judgment factors are started by coordinating trial tests. The Design of Experiment (DOE) system is used to generating the experimental plan and then conducting the experiments according to the plan. After recording the responses Reaction Surface Methodology (RSM) is received for precise expectation numerical models to evaluate the response variables and are created from the experimental information. Artificial Neural Networks (ANNs) have adopted from the MATLAB software for analysing the output response regression and provide the best curve fitting among the input and output variables.

Gas turbine operates at high fluid temperatures and it may damage gas turbine rotor and stator blades. To prevent failure of those blades due to excessive operating temperatures, a specific cooling method known as film cooling can be used during designing of those blades. To have a balance between large heating and excessive cooling of the blades, an optimum cooling technique has been proposed. To obtain cooling effectiveness of the blades, computational analysis has been carried out for this purpose. Variation of cooling effectiveness due to formation of a coolant film over the blade surface, has been computed along the downstream of cooling holes. The numerical model has been well validated with existing experimental literature. The present study compares cooling effectiveness over a range of blowing ratios (M). ANSYS FLUENT solver has been utilized for the numerical analysis using the K-e standard turbulence model with enhanced wall function. Computational results showed that the effectiveness improves up to a certain value with increase in blowing ratios. Further increase in blowing ratios, the effective cooling performance decreases due to coolant jet lift off and intermixing of coolant and mainstream fluid flow. The best cooling performance were obtained with blowing ratio (M) = 1.00.

This dataset comprises the characterizations, tribological and thermal properties of Silicon carbide (SiC) reinforced Nylon 6 (N6) or Polyamide 6 composites. The dataset illustrates the tribological properties such as coefficient of friction, wear and it also describes the characterizations and thermal stability of polyamide composites by varying the weight percentages from 5 - 30wt.% The composites samples were fabricated by injection moulding method. The tribological, characterization and thermal behaviors were determined by wear test, characterizations were carried out by Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FTIR), Thermal stability, degradation performed by Thermogravimetric Analysis (TGA) and Derivative Thermogravimetry (DTG) of the polyamide composites. The dataset helps the readers to understand the significant characteristics of the SiC reinforced N6 composites. However, it is revealed that the addition of SIC can enhance the N6 properties. The preparation of N6 polymer composites findings were useful with good tribological (highly wear resistive) and thermal stability characteristics. This composite can be used for high impact stress parts of gears application.

Reactive power is an essential component for the smooth flow of the apparent power in the power networks. Generators are prime source for reactive power generation, to meet the network reactive power demand of network and load. This result in excessive flow of reactive power over the transmission corridors and may lead to voltage instability and uneconomical operation of network. The control of reactive power in a small power system is straight forward, particularly when the load is reasonably stable/steady. However the control of reactive power is highly challenging for the power utilities operators in large power systems, where the power network consists of long distance power lines and highly variant load due to wide varying seasonal conditions. In this research article a simple reactive power management algorithm has been presented, so as to manage the reactive power flow in Northern Region of Indian grid which is experiencing wide variation in the daily and seasonal load curve. The finding of this work are in concurrence with the Indian grid code and are recommended to the northern region of Indian grid to manage their reactive power demand for next few years.

Laser drilling has swiftly become an economical and well-regulated substitute to conventional hole drilling methods such as wire EDM, punching, broaching, or other prevalent destructive processes, because of cleanliness, accurate results, precise holes, fast material removal rate, and possibility to make holes. Prompt expansion of laser technology in current years gave us facility to regulate laser input factors such as lamp current, pulse frequency, air pressure, and pulse width. The dimensional accuracy and quality of holes are very important for some specific applications of holes. Circularity of drilled hole at entry and exit, and taper are very important attributes which influence the quality of a drilled hole in laser drilling. For this reason, the experimentation based on central composite design is carried out on austenitic stainless steel for examining the effect of laser parameters, i.e., lamp current, pulse frequency, gas pressure, and pulse width, on the quality of drilled holes. A total of 31 experiments were carried out. Later, the models were predicted for output responses using response surface methodology and then tested for adequacy. It is found that the response surface methodology (RSM) predicted models are in close agreement with the experimental values. Hence, the models may be further used for optimization of process parameters using evolutionary algorithms.

Assessment of clusters is needed for effective speech data clustering. Traditional speech clustering methods produce the clustering results without a prior knowledge of number of speakers (or clusters). This is one of the key issues and is addressed in proposed work by visual approaches. A visual approach delivers the results in visual images that are useful for assessing the number of clusters by the counting of square shaped dark blocks. This paper is primarily focused on assessment of speakers (or clusters) and it determines effective clusters of unlabeled speech utterances. Efficiency of proposed work is demonstrated in experimental section with real time speech datasets.

Gas turbines are extremely complex & expensive machines that are subjected to various operating and environmental conditions. Increased customer attention towards higher efficiency is driving the industry to move to higher firing temperatures, which imparts higher thermal & mechanical loads on engine components. This in turn demands higher reliability levels for the engine components to ensure availability and safety of the machine. An effective modeling approach, which can accurately predict the thermal behavior of various components of a gas turbine, can be used to understand the critical regions, locate probable areas of failure, and to improve the overall design. This paper presents a methodology to perform steady state thermal analysis of gas turbine flange to flange components (excluding the main flow path,) using a 2D FE model. A brief overview of the in-house tools and the modeling approach adopted to capture the complex physics using these tools are discussed. The results from this FE analysis are rigorously validated with data collected from various test campaigns of GE industrial Frame5 gas turbines. Several sensitivity studies were performed to study the impact of the uncertainties and to improve the thermal predictions compared to measurements. Studies using CFD tools and hand calculations were also performed to validate assumptions. This approach gives a thorough understanding of how a vast thermal model of gas turbine is developed and validated using test data, resulting in the improvement of thermal predictions of critical components.

Stories from the Indian epics, especially the Ramayana and the Mahabharatha, were the initial narrative sources for filmmaking in India. These films, popularly known as mythologicals, played a decisive role in establishing the Indian film industries in the silent, as well as sound, eras. In the period between the making of the first Indian silent mythological film Raja Harishchandra (D.G. Phalke, India, 1913) and 1919, 25 films were produced in India and most of them were mythologicals. However, by the 1940s, the pan-Indian popularity of mythologicals declined and they continued as low-budget films, circulating at the margins of the Hindi cinema exhibition sector until the 1980s. Despite the national death of the mythological, Madras emerged as a major film industrial base with mythologicals as a dominant genre after the advent of sound in 1931. This popularity of the mythological in South India was much criticized by the ‘literary public’, but they continued to circulate as a dominant genre, unlike in other Indian regional cinemas. More specifically, the mythological had a rather long and significant presence in Telugu cinema as it remained a commercially viable genre until as late as 1980.1 Given the significance of the mythological in the history of Indian film culture, it is a matter of concern that this genre has neither been adequately historicized nor critically commented on by most of the histories and critical writings on Indian cinema until recently.