Towards hybrid nanofluids: Preparation, thermophysical properties, applications, and challenges

The cutting fluid is significant in any metal cutting operation, for cooling the cutting tool and the surface of the workpiece, by lubricating the tool-workpiece interface and removing chips from the cutting zone. Recently, many researchers have been focusing on minimum quantity lubrication (MQL) among the numerous methods existing on the application of the coolant as it reduces the usage of coolant by spurting a mixture of compressed air and cutting fluid in an improved way instead of flood cooling. The MQL method has been demonstrated to be appropriate as it fulfills the necessities of ‘green’ machining. In the current study, firstly, various lubrication methods were introduced which are used in machining processes, and then, basic machining processes used in manufacturing industries such as grinding, milling, turning, and drilling have been discussed. The comprehensive review of various nanofluids (NFs) used as lubricants by different researchers for machining process is presented. Furthermore, some cases of utilizing NFs in machining operations have been reported briefly in a table. Based on the studies, it can be concluded that utilizing NFs as coolant and lubricant lead to lower tool temperature, tool wear, higher surface quality, and less environmental dangers. However, the high cost of nanoparticles, need for devices, clustering, and sediment are still challenges for the NF applications in metalworking operations. At last, the article identifies the opportunities for using NFs as lubricants in the future. It should be stated that this work offers a clear guideline for utilizing MQL and MQL-nanofluid approaches in machining processes. This guideline shows the physical, tribological, and heat transfer mechanisms associated with employing such cooling/lubrication approaches and their effects on different machining quality characteristics such as tool wear, surface integrity, and cutting forces.

A comprehensive review on minimum quantity lubrication (MQL) in machining processes using nano-cutting fluids

Tribology of enhanced turning using biolubricants: A comparative assessment

Nanofluid: Potential evaluation in automotive radiator

Metal cutting fluids (MCFs) under flood conditions do not meet the urgent needs of reducing carbon emission. Biolubricant-based minimum quantity lubrication (MQL) is an effective alternative to flood lubrication. However, pneumatic atomization MQL has poor atomization properties, which is detrimental to occupational health. Therefore, electrostatic atomization MQL requires preliminary exploratory studies. However, systematic reviews are lacking in terms of capturing the current research status and development direction of this technology. This study aims to provide a comprehensive review and critical assessment of the existing understanding of electrostatic atomization MQL. This research can be used by scientists to gain insights into the action mechanism, theoretical basis, machining performance, and development direction of this technology. First, the critical equipment, eco-friendly atomization media (biolubricants), and empowering mechanisms of electrostatic atomization MQL are presented. Second, the advanced lubrication and heat transfer mechanisms of biolubricants are revealed by quantitatively comparing MQL with MCF-based wet machining. Third, the distinctive wetting and infiltration mechanisms of electrostatic atomization MQL, combined with its unique empowering mechanism and atomization method, are compared with those of pneumatic atomization MQL. Previous experiments have shown that electrostatic atomization MQL can reduce tool wear by 42.4% in metal cutting and improve the machined surface R a by 47% compared with pneumatic atomization MQL. Finally, future development directions, including the improvement of the coordination parameters and equipment integration aspects, are proposed.

https://iopscience.iop.org/article/10.1088/2631-7990/ac9652/pdf

Electrostatic atomization minimum quantity lubrication machining: from mechanism to application

Performance evaluation of aluminium 6063 drilling under the influence of nanofluid minimum quantity lubrication

Experimental investigation on the performance of MQL drilling of AISI 321 stainless steel using nano-graphene enhanced vegetable-oil-based cutting fluid

Performance evaluation of the minimum quantity lubrication with Al2O3- mixed vegetable-oil-based cutting fluid in drilling of AISI 321 stainless steel

Due to environmental issue and stringent rules over defilement and contamination of the environment, the demand for renewable and biodegradable cutting fluids is increasing. In this study, an eco-friendly minimum quantity lubrication (MQL) technique using vegetable oil–based cutting fluid (rapeseed oil) by varying MQL flow rate and MQL pressure was investigated in the grinding of AISI 202 stainless steel. In addition to explore the cooling capabilities of rapeseed oil, nano-MoS2 was added to the rapeseed oil to prepare different concentrations (0.5 wt% and 1.0 wt%) of nanofluids. The main objective of this experiment is to examine the performance of different grinding environments (dry, flood, pure MQL, and nanofluid MQL) with respect to grinding characteristics, namely, grinding forces, surface morphology, surface roughness, and temperature. Experimental results revealed that NFMQL grinding with vegetable oil was performed much superior as compared with the dry, wet, and pure MQL machining. The lowest specific normal force and tangential force are observed to be 9.2 N/mm and 0.76 N/mm respectively under 1.0 wt% concentration of MoS2 nanoparticles at oil flow rate of 120 ml/h and air pressure 90 psi under MQL grinding condition, which decreased by 43% and 33%, respectively, as compared with dry conditions. Furthermore, the application of nanofluid also leads to the reduction of surface roughness and surface temperature. MQL application with MoS2 nanofluid helps in effective flushing of chip material from the grinding zone, thereby improving the lubrication and cooling capabilities during the grinding of the AISI 202 stainless steel. In summary, appropriately chosen minimum quantity lubrication parameters can enhance the lubrication and cooling properties of the oil film and improve the grinding characteristics.

Performance evaluation of minimum quantity lubrication technique in grinding of AISI 202 stainless steel using nano-MoS2 with vegetable-based cutting fluid

The implementation of sustainable manufacturing techniques to make machining operations more eco-friendly is a demanding issue that has gained attention from academic and industrial sectors. In some machining operations, a large quantity of machining fluids is wasted to make machining easier, especially during the machining of difficult-to-machine materials such as stainless steel. In such circumstances, many researchers are investigating eco-friendly techniques. Therefore, in this study, effects of minimum quantity lubrication (MQL) with MoS2-enhanced vegetable-oil-based cutting fluid on the drilling characteristics of AISI 321 stainless steel are investigated. The main aim of this study is to analyse the machining performance of various coolant–lubricant strategies, namely dry, flood, pure MQL, and three nanofluid MQL (NFMQL) with regard to thrust force and torque, surface roughness, friction coefficient, chip morphology and tool wear mechanism in drilling of stainless steel (AISI 321). Research findings indicated that NFMQL drilling conditions have given excellent drilling performance by improving drilling characteristics than pure MQL, dry and flood drilling. Among the NFMQL drilling conditions, 1.5 wt.% nano-MoS2 in sunflower oil-based MQL condition provided better cooling–lubrication effect and improved the drilling characteristics followed by 1.0 wt.% and 0.5 wt.% nano-MoS2 in sunflower oil-based MQL conditions. The 1.5 wt.% nano-MoS2 in sunflower oil-based MQL drilling had resulted in 43.2%, 68.9%, 56.8% and 41.6% reduced values of thrust force, torque, surface roughness and COF, respectively, at the 30th hole in comparison with flood drilling. Moreover, noticeable improvement in the chip morphology and tool wear rate has been achieved while drilling under NFMQL environments. The better drilling performance of nanofluid MQL may be attributed to the fact that nanoparticles (MoS2) in sunflower oil offer excellent cooling–lubrication features and provide strength to the oil film at the tool–workpiece interface. In addition, nano-MoS2 particles have high surface activity and are easily adsorbed onto the contacting surfaces, thereby maintaining the lubrication effect.

Tribological characteristics and drilling performance of nano-MoS2-enhanced vegetable oil-based cutting fluid using eco-friendly MQL technique in drilling of AISI 321 stainless steel

Amrit Pal

Papers

Performance evaluation of aluminium 6063 drilling under the influence of nanofluid minimum quantity lubrication

Experimental investigation on the performance of MQL drilling of AISI 321 stainless steel using nano-graphene enhanced vegetable-oil-based cutting fluid

Performance evaluation of the minimum quantity lubrication with Al2O3- mixed vegetable-oil-based cutting fluid in drilling of AISI 321 stainless steel

Performance evaluation of minimum quantity lubrication technique in grinding of AISI 202 stainless steel using nano-MoS2 with vegetable-based cutting fluid

Tribological characteristics and drilling performance of nano-MoS2-enhanced vegetable oil-based cutting fluid using eco-friendly MQL technique in drilling of AISI 321 stainless steel