Dr Amit Sharma
@juet.ac.in
Assistant Professor (Senior Scale), Mechanical Engineering
Jaypee University of Engineering and Technology, Guna (M.P.), India
RESEARCH INTERESTS
Manufacturing Processes
Scopus Publications
Scopus Publications
Siddhant Pratap Singh, Amit Sharma, Vivekanand Singh, and Sanjay Mishra
IOP Publishing
Abstract In present scenario, natural fibers are the preferred choice of manufactures to fabricate the sustainable polymer matrix composites. These composites may be a good substitute for synthetic materials after achieving the comparable strength with some treatments. Pineapple leaf fiber (PALF) contains high cellulose with low micro fibrillar angle which leads to decent inherent fiber strength. It is used for reinforcement in the proposed work to fabricate the epoxy matrix composite using hand layup method. During testing of composite, the effects of fiber content, type, and orientations on mechanical properties have been examined. Samples were prepared by varying the fiber type (short and long fiber), fiber orientations (at 0°, 90°, and 45°) and fiber contents by weight % (i.e., 5, 10, 15 and 25). The results of mechanical characterization reveal that the tensile and flexural strength for short fiber composite is found maximum at 25% of fiber content (20.85 MPa and 42.70 MPa, respectively). However, long fiber reinforced composite with 5% of fiber content exhibits maximum tensile and flexural strength as: 35.72 MPa and 56.19 MPa. The maximum flexural strength and impact strength of composite were found as 52.98 MPa and 25.30 J m−2, respectively when the fibers are oriented at 0°. The maximum values of water absorption in composite were found as: 1.74% for short fiber and 1.25% for long fiber reinforced composites. The Fourier transform infrared radiation (FTIR) spectroscopy confirms the removal of non-cellulose contents within the composite. Finally, the morphological analysis was carried out to find the debonding, splitting and pull-out of fibers within the composites which are the major reasons of composite failure.
Tasnim Arif and Amit Sharma
SAGE Publications
In the present era of manufacturing, sustainable processes are preferred for healthy and ecofriendly environment. To avoid the environmental pollutants and hazardous fumes during the drilling of Inconel-718 alloy, electrical discharge drilling (EDD) process has been used with deionized water as a dielectric medium in the present study. The process performance in terms of metal removal rate (MRR) and hole taper has been controlled by using four process variables such as discharge current, pulseduration, pulse interval and dielectric flushing pressure. The experiments were designed with the help of Box Behnken design (BBD) technique and further, the experimental results have been analyzed to optimize the process performance by using the grey-based fuzzy logic approach. The application of optimization approach has improved the MRR by 62.6% and hole taper is reduced by 20.23%. The parametric study has been carried out to examine the process behaviour with the variation of variables and pulse duration is found as most significant parameter for the study.
I. Ferretto, A. Sharma, D. Kim, N.M. Della Ventura, X. Maeder, J. Michler, E. Hosseini, W.J. Lee, and C. Leinenbach
Elsevier BV
Jyotish Patidar, Amit Sharma, Siarhei Zhuk, Giacomo Lorenzin, Claudia Cancellieri, Martin F. Sarott, Morgan Trassin, Kerstin Thorwarth, Johann Michler, and Sebastian Siol
Elsevier BV
Amit Sharma and Priyanka Joshi
Springer Science and Business Media LLC
Md. Tasnim Arif and Amit Sharma
Springer Nature Singapore
V. Dwivedi, P. Mandla, D. Gupta, R. Chandel, and A. Sharma
Elsevier BV
Amit Sharma and Sumit Sharma
Informa UK Limited
ABSTRACT The effectiveness of coatings depends upon various factors and adhesion of the coating to a metallic surface is one of them. Polyurethane (PU) and polytetrafluoroethylene (PTFE) are widely used polymeric coatings for the protection of metallic surfaces. The adhesion of PU and PTFE films on the aluminium oxide substrate is investigated by employing MD simulations. The effect of temperature variation on both the polymeric films has been also studied. Results depict that as the temperature increases the adhesion energy of both the polymers increases in the range from 273.15 K to 298 K. However, there is no such applications of these polymeric coatings at higher temperature like 548 K, the interaction energy is also calculated at 548 K to predict the behaviour of these polymers at elevated temperatures. PU was found to be more thermally stable compared to PTFE. Moreover, PU adhesion with the aluminium oxide surface was much greater when compared to PTFE which possibly resulted from the existence of oxygen atoms in PU which are responsible for greater adhesion between polymer and metal surface.
Amit Sharma, Priyanka Joshi, and Kuldeep K Saxena
SAGE Publications
Al alloys are the second most useful metal worldwide after the steel due to its high strength-to-weight ratio and corrosion resistance properties. In the present scenario, for creating contours in the sheet metals with close tolerances and high precision, laser beam cutting is preferred. During laser beam cutting of Al alloys, the reflectivity of the alloy possesses some difficulties to absorb the laser light. Such problems can be avoided using the shorter wavelength laser. This paper presents the modeling and optimization of kerf characteristics in Nd-YAG laser cutting of Al 6061-T6 sheet. In this study, kerf width (top and bottom side) and top kerf deviation are considered as kerf characteristics which are the functions of lamp current, pulse width, pulse frequency, and cutting speed. Box–Behnken design has been used for conducting the experiments and the experimental results have been further used for developing the response surface models and optimizing the responses using response surface methodology and grey relational analysis, respectively. Application of grey relational analysis has reduced the bottom kerf width by 12.5% and 7.75% along with straight and curved cut profiles respectively.
P. Joshi, A. Sharma, and V. Singh
Springer Singapore
Laser cutting is the most acceptable method to create complex geometries where it is difficult to cut sheet metal with close tolerances and high precision. In this study, empirical models for top kerf deviation and kef taper have been developed using response surface methodology (RSM). Box–Behnken Design (BBD)-based experiments on Ni-superalloy sheet have been conducted in laser cutting process. Lamp current, duration of pulse, frequency of pulses and speed of cutting are taken as process variables. The prime application of RSM is to build up a functional correlation between input and output parameters of the process. This relationship is analysed using analysis of variance (ANOVA) for the adequacy of models, and subsequently, adequate models have been used to predict the process behaviour.
P. Joshi, A. Sharma, V. Yadava, and Y. K. Modi
Springer Singapore
Priyanka Joshi and Amit Sharma
Elsevier BV
Abstract In this paper, laser cutting of Aluminum alloy (Al 6061-T6) thin sheet has been carried out using pulsed Nd-YAG laser to investigate the dimensional accuracy of the kerf geometry and zone of the metallurgical changes in the sheetmetal. These responses are quantified in terms of kerf taper and heat affected zone for the study. The taper in the kerf and heat affected zone are the functions of four laser cutting parameters namely: lamp current, pulse width, pulse frequency and cutting speed and different settings of these laser cutting parameters are utilized to analyze the responses. In order to analyze the experimental results, a systematic design of experiments namely Box Behnken design (BBD) has been employed to conduct the experiments. Further, the experimental results have been optimized using hybrid approach of grey relational analysis and fuzzy logic. The analysis of variance (ANOVA) has been carried out to determine the significance of laser cutting parameters for the process where pulse frequency is found as the most leading parameter in the study. The application of hybrid approach is capable to reduce the kerf taper and HAZ of laser cut kerf by 2.52% and 42.32%, respectively.
Priyanka Joshi and Amit Sharma
Springer Science and Business Media LLC
Nickel-based superalloys are widely used in the aircraft and nuclear reactor industries due to their high strength-to-weight ratio and corrosion resistance properties at elevated temperatures. Typical applications of these superalloys demand technologically advanced cutting processes to create intricate shapes in macro- and microfeature sizes with exceptional good quality. These objectives can be obtained using laser beam cutting process. In this paper, multiple laser cut quality characteristics (i.e. top kerf deviation, bottom kerf deviation and kerf taper) are optimized simultaneously using grey relational analysis coupled with fuzzy logic during pulsed Nd-YAG laser cutting of thin Ni-based superalloy sheet. These laser cut characteristics are the functions of four laser cutting parameters, namely: lamp current, pulse width, pulse frequency and cutting speed where lamp current is considered as a new cutting parameter. The different values of lamp current are utilized to find the different levels of pumping energy which is further utilized to generate the laser energy. Further, laser cut results have been obtained by performing the experiments using Box–Behnken design (BBD). The results have been analysed using grey-fuzzy method to predict the optimum level of cutting parameters. The application of grey-fuzzy is capable to reduce the top kerf deviation, bottom kerf deviation and kerf taper in laser cut kerf by 47.69, 25.96 and 7.59%, respectively.
Y. Shrivastava, B. Singh, and A. Sharma
Springer Science and Business Media LLC
Regenerative chatter is a predominant phenomenon in the turning process. In machining of metals, identification of tool chatter is essential in order to improve productivity and thus enhance the tool life. In spite of the immense work done within this domain, still many facets are yet to be explored. For detection of chatter many researchers have used sensors, but usually measured chatter signals from sensors are contaminated by background noise and other disturbances. Hence, it is essential to develop an efficient signal processing technique by the aid of which induced noise can be removed and onset of chatter can be detected at the earliest. In present work the scholar has explored four objectives. Firstly, turning process has been simulated using simulink tool Matlab and signals have been recorded at different combinations of cutting parameters. The simulation has been validated by comparing the simulated and experimentally recorded signals. Secondly, wavelet denoising technique has been implemented for denoising the noisy signals. Moreover, the denoising technique have been validated by comparing the results with simulated noise free signals. Thirdly, the peak frequency have been determined at different combination of cutting parameter by power spectral density analysis. Lastly, a new output parameter chatter index (CI) has been calculated. CI makes it convenient to analysis the severity of chatter.
Priyanka Joshi, Amit Sharma, and Yashwant Kumar Modi
Elsevier BV
Abstract The present investigation deals with the modeling and optimization of multiple quality characteristics of kerf geometry during pulsed Nd: YAG laser cutting of nickel based superalloy thin sheet along the straight cut profile. Top kerf deviation and kerf taper are considered as quality characteristics. These laser cut quality characteristics are the functions of four input parameters are namely: lamp current, Pulse duration, Pulse repetition rate and Scanning speed. Box-Behnken design (BBD) based experiments have been conducted to obtain experimental results of cut quality characteristics for the study. The experimental results have been analyzed for developing models and optimizing the responses using response surface methodology (RSM).
Yogesh Shrivastava, Bhagat Singh, and Amit Sharma
Elsevier BV
Abstract Regenerative chatter degrades the high-performance level and useful life of machinery. Despite the immense work done within this domain, still many features related to regenerative chatter remains un-explored. Previous researchers have suggested various techniques to explore the tool chatter based on acquired experimental chatter spectrum. However, most of them have overlooked the effect of background noise and other disturbances. In order to extract the exact chatter features, it is essential to sieve out the noise contents from these signals. This aforesaid fact motivated the present research work. In the present study, recorded chatter signal have been pre-processed using wavelet denoising (WD). Thereafter, empirical mode decomposition (EMD) technique have been used to identify the chatter frequency. Further, the dependency of chatter on cutting parameters has been explored
Amit Sharma and Vinod Yadava
Elsevier BV
Abstract Cutting of sheet material is considered as an important process due to its relevance among products of everyday life such as aircrafts, ships, cars, furniture etc. Among various sheet cutting processes (ASCPs), laser beam cutting is one of the most capable ASCP to create complex geometries with stringent design requirements in difficult-to-cut sheet materials. Based on the recent research work in the area of sheet cutting, it is found that the Nd-YAG laser is used for cutting of sheet material in general and reflective sheet material in particular. This paper reviews the experimental analysis of Nd-YAG laser cutting process, carried out to study the influence of laser cutting parameters on the process performance index. The significance of experimental modeling and different optimization approaches employed by various researchers has also been discussed in this study.
Amit Sharma, Vinod Yadava, and K. B. Judal
IGI Global
In the present study, a novel technique, namely, evolutionary non-dominated sorting genetic algorithm-II (NSGA-II) was used in conjunction with developed artificial neural network (ANN) model to select optimal process parameters for achieving the better process performance in LBC. First, ANN with backpropagation algorithm was used to model the LBC of nickel based superalloy sheets. The input process parameters taken were oxygen pressure, pulse width, pulse frequency and cutting speed. The performance characteristics of interest in nickel based superalloy thin sheet cutting are average kerf taper and surface roughness. The ANN model was trained and tested using the experimental data obtained through experimentation on pulsed Nd-YAG laser beam machining system. The 4-10-11-2 backpropagation architecture was found more accurate and generalized for given problem with good prediction capability. The results show that the developed modelling and optimization tool is effective for process parameter optimization in LBC process. The optimization of the process suggests that for achieving high cut quality characteristics the pulse width, pulse frequency and cutting speed are set to lower limit within the available range and gas pressure is set to a level which is sufficient to remove the molten metal from the kerf.
Amit Sharma and Vinod Yadava
Inderscience Publishers
This paper presents an application of DOE-based hybrid approach for the determination of preferred operating laser cutting parameters which minimises the average kerf taper (Ta) and average surface roughness (Ra) together during pulsed Nd: YAG laser cutting of thin aluminium alloy sheet for straight profile. The hybrid approach, comprises of Taguchi methodology (TM) and response surface methodology (RSM), has been applied to achieve the better cut qualities within the existing resources. The input process parameters taken are oxygen pressure, pulse width, pulse frequency and cutting speed. The approach first uses the Taguchi quality loss function to find the optimum level of laser cutting parameters. The optimum values of input cutting parameters so obtained are further used as a central value in RSM. Further, the experiments are conducted by using the central composite rotatable design (CCRD) matrix. Subsequently, the laser cutting parameters have been optimised by using the MINITAB software. The application of hybrid approach has reduced Ta by 15% whereas it has been reduced by 6.7% with the application of TM only.
Amit Sharma and Vinod Yadava
Elsevier BV
Abstract CO2 Lasers in general, and Nd:YAG lasers in particular, are widely used for cutting of reflective sheetmetals to obtain the exceptional good quality cut. Due to shorter wavelength of Nd:YAG laser, it is reflected by lesser extent from the metallic surfaces. This paper presents the modelling and optimization of cut quality characteristics during Nd:YAG laser cutting of aluminum alloy thin sheet along the curved profile. The cut quality characteristics considered are average kerf deviation (Da) and average kerf taper (Ta). The essential input process parameters are identified as arc radius of curve profile, oxygen pressure, pulse width, pulse frequency and cutting speed. First, second order response surface model was developed for each Da and Ta using hybrid approach of Taguchi methodology (TM) and response surface methodology (RSM). The effect of input process parameters on each cut quality (Da and Ta) was also studied. Second, preferred operating laser cutting parameters were obtained using grey relational analysis (GRA) with entropy measurement (EM) to minimize Da and Ta together. In the present study a L27 orthogonal array (OA) is used for experimentation. The entropy measurement (EM) method is employed for the calculation of weights corresponding to each quality characteristic Da and Ta. Finally, significant improvement in Ta has been observed from the verification results.
Amit Sharma and Vinod Yadava
Elsevier BV
Abstract Thin sheets of aluminium alloys are widely used in aerospace and automotive industries for specific applications. Nd:YAG laser beam cutting is one of the most promising sheetmetal cutting process for cutting sheets for any profile. Al-alloy sheets are difficult to cut by laser beam because of its highly reflective nature. This paper presents modelling and optimization of cut quality during pulsed Nd:YAG laser cutting of thin Al-alloy sheet for straight profile. In the present study, four input process parameters such as oxygen pressure, pulse width, pulse frequency, and cutting speed and two output parameters such as average kerf taper (Ta) and average surface roughness (Ra) are considered. The hybrid approach comprising of Taguchi methodology (TM) and response surface methodology (RSM) is used for modelling whereas multi-objective optimization is performed using hybrid approach of TM and grey relational analysis (GRA) coupled with entropy measurement methodology. The entropy measurement methodology is employed for the calculation of weight corresponding to each quality characteristic. The results indicate that the hybrid approaches applied for modelling and optimization of the LBC process are reasonable.
Amit Sharma and Vinod Yadava
Inderscience Publishers
This paper presents a hybrid approach for optimising laser straight cutting of Ni-based superalloy thin sheet. The hybrid approach comprises of Taguchi methodology (TM) and response surface methodology (RSM). The input process parameters taken are oxygen pressure pulse width pulse frequency and cutting speed. The experimental output characteristics of interest in Ni-based superalloy thin sheet cutting are average kerf taper (Ta) and average surface roughness (Ra). First the values of optimum input parameters are obtained using TM only. The optimum value of input parameters so obtained are further used as central value in RSM. Further experiments are performed using central composite rotatable design (CCRD) matrix. Finally second order response surface models are developed as well as optimum parameters are found using MINITAB software. A remarkable improvement in both the quality characteristics is found when hybrid approach is applied as compared to application of Taguchi approach only.