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2018 - 201942020 - 20231
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Subject: Industrial and Production Engineering × Start date: 2015 × Type: Thesis × Thesis Type: Ph.D ×
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Now showing 1 - 5 of 5
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    ThesisItemOpen Access
    MODELING AND SIMULATION OF CUTTING FORCES IN SURFACE GRINDING PROCESS AT MICRO LEVEL USING MATLAB
    (G. B. Pant University of Agriculture & Technology, Pantnagar-263145, 2023-02) Singh, Yogendra Kumar; Pankaj
    Grinding is a major manufacturing process that accounts for approximately 20– 25% of total machining expenditures in industrialized countries. Everything used todayhas been machined by grinding at some point in its manufacturing process or has been produced by machines that owe their functionality to grinding operations. Grinding forces play a key role in the grinding process by influencing the specific power consumption, heat generation at the interface of abrasive cutting grains and the workpiece, quality of the ground workpiece surface and various other performance parameters. So, a mathematical model to estimate the grinding forces would help to achieve the target. Previously developed models were usually based on the assumption which might contradict with the reality as they didn’t consider the grain-workpiece interaction at the micro level (i.e., rubbing, ploughing and cutting). Also, most previous studies could only be used to predict average values on wheel basis of grinding forces because the most models were built based on average grain cutting depth or average chip thickness, and none of the grinding force details at the micro level. A new model to predict the grinding forces at micro levelof grain-workpiece interaction have been developed in the present study and validated with help of MATLAB and data available in the previous studies. The effects of grinding parameters such as depth of cut, workpiece speed, wheel speed and size of abrasive grains was studied. The predicted grinding forces were almost identical to the grinding forces experimentally estimated by the previous researchers, with an average percentage error of 6.09%. It was found that the Size of the abrasive grains (abrasive grit number) have the largest impact on rubbing, ploughing and cutting contributions. Depths of cut have the second largest effects and the dominant force component could probably be changed from rubbing to cutting by using different cut depths. The effects of wheel speeds can also be seen: fast wheel speeds lead to less rubbing forces and more cutting forces, while the effects of workpiece feed rates seem to be limited. Therefore, high wheel speeds and large workpiece feed rates are recommended to achieve high material removal rates. (
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    ThesisItemOpen Access
    Parametric optimization of friction stir welding for Al-Li alloy using Taguchi method
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-05) Pandey, Rachna; Jadoun, R.S.
    Effect of process parameters on friction stir welding (FSW) process characteristics and mechanical properties of weld joints have been studied. Design of experiment (DOE) approach was applied for understanding the effects of selected FSW process parameters. An L9 orthogonal array was used to investigate the effect of welding speed, rotational speed and tilt angle. An optimum tool profile was selected on the basis of trial runs made prior to final experiments. In the present research, FSW of AA8090 Al-Li alloy has been performed using conventional vertical milling machine. Numerous trial experiments were performed to establish the principal FSW process parameters to be varied during the research to investigate their effect on weld quality. The selection of tool pin, shoulder diameter and material of tool was also done through a number of trial experiments. Welding speed, rotational speed and tilt angle were selected as the FSW process parameters and three levels of each parameter from within the feasible range were considered. The experiments were performed in accordance with Taguchi’s L9 orthogonal array. Mechanical test was performed for every weld specimen. The weld quality was analyzed through tensile tests and hardness tests. The effect of process parameter on weld quality characteristics such as tensile strength and hardness was analyzed. Analysis of results of mechanical tests revealed significant effect of all three FSW parameters on tensile strength and hardness.
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    ThesisItemOpen Access
    Process parameters optimization and experimental investigation of friction stir welded AA1350 aluminium butt joint for thick plates using Taguchi method
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-04) Tewari, Maneesh; Jadoun, R.S.
    In the present experimental work, friction stir butt welding of thick AA1350 grade Aluminium plates has been taken as basis of research work. As the previous published work shows research work upto 6-7 mm thicknesses, plate thickness of 12.7mm ( above 10mm) was selected for our research work. The three welding parameters- spindle rotation, welding speed and tool tilt angle were considered as input parameters and FSW was performed on 12.7 mm thick AA1350 Grade Aluminium plates. Using Taguchi L9 orthogonal array methodology , the experiments were planned and conducted. Tensile strength, Electrical conductivity and hardness measured on test samples were chosen as output response factors. After doing the trial runs on Universal Milling Machine, three different workable settings for selected parameters were obtained and optimum levels of setting and process variance were achieved by Taguchi method. The confirmatory experiments were later conducted to validate the optimum parameters setting and the results were compared. SEM analysis was performed on good as well as bad samples and defect analysis was done. From the results, it was concluded that: 1) Maximum Tensile strength was found at welding speed of 80mm/min, Tool rotation of 900 rpm and Tool tilt angle of 2⁰. 2) Maximum nugget hardness was found at welding speed of 125mm/min, tool rotation of 560rpm and tool tilt angle of 0⁰. 3) Maximum electrical conductivity was found at welding speed of 125mm/min, tool rotation of 560rpm and tool tilt angle of 0⁰.
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    ThesisItemOpen Access
    Modeling and optimization of Electro Discharge Machining (EDM) process parameters for machining of inconel 600 super alloy
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-01) Choudhary, Sushil Kumar; Jadoun, R.S.
    In last few years, Inconel 600 superalloy gained much attention of researchers due to its properties viz. high impact strength at room temperature, high hardness, high melting point, high electrically conductivity, corrosion resistance etc. Due to such excellent properties, Inconel 600 superalloy is an ideal choice for the numerous industrial applications, such as manufacturing the components related to aero-engine, spacecraft, nuclear, chemical, food processing, furnace, gas turbine, fixtures, heat exchanger, roller and hearths etc. However, the machining process in Inconel 600 superalloy with traditional machining processes is very difficult due to its poor machinability, high cost and more time consumption. In non-traditional machining processes, electrical discharge machining (EDM) has been regarded as the most efficient for the machining of Inconel 600 superalloy. Many investigations have already been done on the machining of Inconel 600 superalloy with EDM using different electrodes (copper, brass, graphite, molybdenum, copper tungsten). However, the effect of tungsten carbide as a tool electrode, on the machining of Inconel 600 superalloy has not been available in the literature. Therefore, machining of Inconel 600 superalloy with EDM using tungsten carbide as a tool electrode has been presented in this work to determine the effect of different process parameters on the various machining performance parameters. Experimental work has been planned in two phases. In the first phase, parametric optimization of EDM process for performance characteristics performed using Taguchi method. An orthogonal array (OA) L9 was used to conduct the experiments at three levels. Signal to Noise ratio (S/N) and analysis of variance (ANOVA) were employed to study the EDM performance characteristics. Optimization of parameters was done by Taguchi method using statistical software MINITAB-17. Confirmation tests were carried out with optimal levels of process parameters to validate the Taguchi's optimization method. The above results were validated by conducting confirmation experiments. In second phase, mathematical models have been developed for various performance characteristics of the EDM process by RSM using statistical software Design-Expert-9.0. The experiments performed using face centered central composite design and 30 runs were used to conduct the experiments. A standard second-order experimental design called face-centered central composite design (CCD) has been adopted for analyzing and modeling the EDM process parameters for performance characteristics. Predicted optimal ranges of MRR, TWR, WR, OC and SR at 95% confidence level were 30.67 mm3/min, 0.551mm3/min, 2.225, 0.012 mm and 6.684 μm respectively, which were validated by conducting confirmation experiments. Confirmation tests were also carried out with optimal levels of process parameters to validate the desirability function combination with RSM.
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    ThesisItemOpen Access
    Investigations on machinability parameters of 7068 aluminium alloy using tin coated carbide positive rake tool bits
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2018-01) Kshetri, Rahul; Ajay
    The current work presents findings from the experimental investigation of the effect of cutting speed, feed rate and depth of cut on the feed force, cutting force and surface roughness, tool wear during turning of Aluminium alloy 7068, by using TiN coated carbide tool in dry condition. There are several dependent and independent parameters involved during orthogonal turning. Independent parameter are cutting speed, feed and depth of cut whereas, dependent parameters are feed force and cutting force components; measured by dynamometer. Due to generation of temperature in different zones, overall effect of temperature on tool tips has been measured by using thermal camera. The investigation is important because Al-7068 is difficult to machine and there is insufficient coverage on its study. Experimental work is carried out with the help of high speed lathe machine followed by measurement of force components and temperature at different input parameters. After machining, tool wear and surface roughness have been measured using scanning electron microscope (SEM) and surface roughness tester. Mathematical model in between all dependent and independent parameters have been developed using RSM. The causes of tool wear and their mechanism are also discussed in the present work. Surface plots are drawn for each mathematical model and their affects in different input parameters are presented with interaction and main affect plots. Tool wear and their mechanism with magnifying views of image are also reported in this work. Recommendations are drawn on the basis of analysis.