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Munish Kumar Gupta,P. Niesłony,Murat Sarikaya,Mehmet Erdi Korkmaz,Mustafa Kuntoğlu,G. M. Królczyk 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.4
The aerospace and automotive industries make extensive use of aluminium and its alloys. Contrarily, machining of aluminium (Al) alloys presents a number of difficulties, including, but not limited to, poor surface finishing, excessive tool wear, decreased productivity etc. Therefore, it’s very important to measure the machining characteristics during machining of aluminium alloy with sustainable cooling strategies. In this work, a new approach of measurement was adopted to measure the critical geometrical aspects of tool wear, surface roughness, power consumption and microhardness while machining AA2024-T351 alloy under dry, minimum quantity lubrication (MQL), liquid nitrogen (LN2) and carbon dioxide (CO2) cooling conditions. Initially, the various aspects of tool wear were studied with the help of Sensofar Confocal Microscope integrated with Mountains map software and then, the other results such as surface roughness, power consumption and microhardness were measured as per the ISO standards. The outcome of these measurement studies confirms that LN2 and CO2 cooling is helpful in improving the machining characteristics of AA2024-T351 alloy. When compared to dry conditions, the surface roughness values of MQL, LN2, and CO2 all have values that are lowered by 11.90%, 30.95%, and 39.28% respectively, and also power consumption values were lowered by 3.11%, 6.46% and 11.5% for MQL, CO2 and LN2 conditions, respectively.
Munish Kumar Gupta,P. Niesłony,Mehmet Erdi Korkmaz,Mustafa Kuntoğlu,G. M. Królczyk,Mustafa Günay,Murat Sarikaya 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.6
Cutting energy must be reduced in order to make machining processes more eco-friendly. More energy was expended for the same amount of material removed, hence a higher specific cutting energy (SCE) implies inefficient material removal. Usually, the type of coolants or lubricants affects the SCE, or the amount of energy needed to cut a given volume of material. Therefore, the present work deals with a study of SCE in the turning of Ti–3Al–2.5V alloy under green cooling strategies. In spite of this, the research effort is also focused on the mechanism of tool wear, surface roughness, and cutting temperature under hybrid cooling, i.e., minimum quantity lubrication (MQL) and cryogenic. The tool wear rate, were explored with tool mapping analysis, and the results were compared with dry, MQL, and liquid nitrogen (LN2) conditions. The tool wear rate analysis claims that the dry condition causes more built up edge (BUE) formation. In addition, the hybrid cooling conditions are helpful in reducing the SCE while machining titanium alloys.
Prashant Kumar,Neeraj Gupta,Nitin Sachdeva,Tarun Sachdeva,Munish Vashishath 대한전자공학회 2020 Journal of semiconductor technology and science Vol.20 No.3
The rapidly growth in semiconductor industry puts huge demand of scalable devices with low standby power for future VLSI chips. The further mitigation in device dimension becomes a challenging task due to the existence of unavoidable short channel effects. The introduction of gate stack and channel engineering in MOSFET devices open a new window for future generation devices. This paper presents gate stack structure with low-κ dielectric material as silicon oxide and replacement of various high-κ dielectric materials to analyze the device performance. The unification of new oxide material in the device enhances the immunity against SCEs and improves the gate leakage current. Dual-Halo Dual-Dielectric Triple Material Surrounding Gate (DH-DD-TM-SG) MOSFET has shown better performance with high dielectric constant materials. The device exhibits more value of transconductance with high-κ dielectrics.
Rashid Ali Laghari,Ning He,Muhammad Jamil,Muhammad Irfan Hussain,Munish Kumar Gupta,Grzegorz M. Krolczyk 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.10 No.6
Metal matrix composites (MMCs) are lightweight, hard materials applied in heavy-duty applications such as automobile, aerospace, and electronics, as well as sports equipment. MMCs reveal exceptional physical and mechanical properties, including high strength, corrosion, wear resistance, higher stiffness, and toughness. However, owing to poor surface finish, accelerated tool wear, and high material removal cost, MMCs are categorized as difficult-to-cut composites. This article reviews sustainable machining under different lubrication and cooling approaches and the economics of the operation for MMCs. The study focuses on optimizing machinability factors, such as surface integrity, chip formation, tool wear, and sustainability analysis. To attain this goal, the review evaluates suitable cutting parameters for Aluminum, Titanium, Magnesium, and Copper-based metal matrix composites, which hitherto have not been explored or summarized comprehensively. This study provides strong guidance regarding selection of precise cutting parameters for MMCs. The findings of this review suggest that different cooling/lubrication technologies can optimize and improve the sustainability and machinability characteristics, extend tool life and surface quality, during the cutting operation.
Serhat Şap,Üsame Ali Usca,Yavuz Selim Tarih,Adem Yar,Mustafa Kuntoğlu,Munish Kumar Gupta 한국정밀공학회 2024 International Journal of Precision Engineering and Vol.11 No.1
Because of their biodegradable and regenerative properties, cellulose nanocrystals derived primarily from naturally occurring cellulose fibers serve as a sustainable and environmentally beneficial material for most applications. Although these nanocrystals are inherently hydrophilic, they can be surface functionalized to suit a wide range of demanding requirements, such as those associated with the creation of high-performance nanocomposites in hydrophobic polymer matrices. Therefore, the present work deals with the application of cellulose-based biodegradable nanocrystals as a lubricant in the machining of PPS composites. In this study, milling process was considered to investigate the influence of the sustainable lubricating conditions on the machinability indexes of PPS composites. As a novel cooling approach, water-based solutions enriched by cellulose nanocrystals with different reinforcements (0.25%, 0.5%, and 1%) were used over known methods such as MQL, conventional flood, and dry. According to the research outcomes, cellulose nanocrystals-based nanofluids provided satisfying contributions on retarding the tool wear and reducing the cutting temperatures considerably. Despite the surface-related results such as roughness, topography and texture are promising for the developed strategy; further investigations will be useful to determine ideal water-particle concentration to improve the quality of the machined surface.