Minimum Quantity Lubrication Research Articles

Effect of applied electric and magnetic fields on surface roughness in minimum quantity lubrication turning using Fe3O4 nano-ferrofluid

PurposeFirst, the effect of magnetic field intensity and nano-ferrofluid concentrations on surface roughness was evaluated in magnetic minimum quantity lubrication (MMQL). Then, the effect of lubricant flow rate and nozzle position on surface roughness was investigated in MQL, MMQL, electrostatic MQL (EMQL) and electromagnetic MQL (EMMQL).Design/methodology/approachThis study examined the performance of MQL under magnetic and electric fields in turning AISI 304 stainless steel in terms of surface roughness and compared the results with those obtained from wet cutting and MQL turning operations. To prepare the nano-ferrofluid used in different states of MQL, Fe3O4 nanoparticles were added to the base fluid.FindingsThe results showed that the surface roughness under the EMMQL technique decreased by 36% and 49.4% on average compared with wet and MQL techniques, respectively. The lubrication technique affected the surface roughness by 90.2%, whereas it was 8.3% for the lubricant flow rate. EMQL and EMMQL techniques had no significant difference in their effects on surface roughness. In the innovative MMQL technique, the nano-ferrofluid concentration of 6% and magnetic field intensity of 93 G resulted in lower surface roughness of the workpiece relative to other counterparts.Originality/valueExamining previously published studies showed that using nano-ferrofluids under a magnetic field for cooling purposes in machining processes have less considered by researchers. This study applies an innovative method of lubrication under the concurrent effect of magnetic and electric fields, called EMMQL, to improve the efficiency of MQL in machining hard-to-cut materials. For comprehensively inspecting the newly presented method, the effects of several parameters, including the nano-ferrofluid concentration, magnetic field intensity, lubricant flow rate and position of lubricant spray nozzle, on the surface roughness of workpiece in turning of AISI 304 stainless steel are investigated.

A Comparative Performance Investigation of Single- and Double-Nozzle Pulse Mode Minimum Quantity Lubrication Systems in Turning Super-Duplex Steel Using a Weighted Pugh Matrix Sustainable Approach

This study investigates the performance comparison of machining of UNS S32750 super-duplex stainless steel under single- and double-nozzle pulse mode minimum quantity lubrication (MQL) conditions. The pulse mode MQL system delivers lubricant pulses at specific intervals. The Taguchi L9 design, with three factors and their three levels, was taken to perform the CNC turning experiments under both single-nozzle and double-nozzle MQL cooling environments. The surface roughness (Ra), tool-flank wear (VB), tool-flank temperature (Tf), power consumption (Pc), and material removal rate (MRR) are evaluated and compared as performance indicators. In comparison to single-nozzle MQL, the responses of Ra, VB, Tf, and Pc were found to be decreased by 11.16%, 21.24%, 7.07%, and 3.16% under double-nozzle conditions, respectively, whereas MRR was found to be 18.37% higher under double-nozzle conditions. The MQL pulse time was found to be an important variable that affects Ra, VB, Tf, and MRR significantly. Under both cooling scenarios, common wears such as abrasion, built-up edges, adhesion, and notch wear are detected. Furthermore, the Pugh matrix-based sustainability evaluation results revealed that the double-nozzle MQL technique was superior to single-nozzle MQL, achieving improved sustainability for machining super-duplex stainless steel.

Surfactant free enhancement to thermophysical and tribological performance of bio-degradable lubricant with nano-friction modifier for sustainable end milling of Incoloy 925

An efficient method of lubrication and cooling for green machining is nanofluid minimum quantity lubrication (NMQL). Compared to other vegetable-based oils, coconut oil has the highest viscosity index, lubricity, and oxidative characteristics, making it a popular trending lubricant for decreasing friction. However, its performance at higher temperatures degrades owing to higher saponification value. In order to improve its performance, the solid nano-friction modifier (hBN) is dispersed in it, and the colloid is called a nanofluid. UV–Vis–NIR spectrophotometer, HR-TEM, and FTIR spectroscopy characterize nanofluid. The stability of nanofluid at 0.3 vol% of hBN has been observed to be the highest compared to other volume fractions. Compared to coconut oil, prepared nanofluid is superior in terms of increased thermal conductivity, thermal stability, and viscosity for all the tested temperature ranges. Nanofluid shows increased viscosity index (VI) by 20%, reduced contact angle by 45%, and lower coefficient of friction (COF) by 32% compared to coconut oil. Further performance of this modified biodegradable nanofluid under Minimum quantity lubrication (MQL) on end milling of Incoloy 925 has been studied. In order to compare the machining performance under different cutting environments, cutting temperature, cutting force, specific cutting energy, power consumption, carbon emission, chip morphology, surface topology/topography, and tool wear were evaluated. Finally, sustainability assessments for different cutting environments have been performed. Biodegradable oil-based NMQL-assisted machining has performed better than dry and MQL-assisted machining.

The machinability of titanium alloy thin-wall parts in cooling minimum quantity lubrication (CMQL) environments

The machining of thin-wall components made of titanium alloys is challenging because the poor machinability of the material leads to severe problems such as accelerated tool wear and poor surface quality, while the weak rigidity of the thin-wall structure results in unavoidable vibration and surface form errors. To address these issues, this paper investigated the mechanisms and performance of cooling minimum quantity lubrication (CMQL) in milling titanium thin-wall parts. To verify the efficiency of CMQL, different cooling/lubrication strategies, including conventional flood cooling, minimum quantity lubrication (MQL) and CMQL with different temperature levels, were investigated. The cutting force, tool wear state, chip formation, surface integrity, and surface form errors were compared and analysed in detail. The experiment results show that MQL is inadequate at higher spindle speeds due to its ineffective cooling capacity and weakened lubrication ability. In contrast, CMQL has demonstrated its feasibility and superiority in milling titanium thin-wall parts under all conditions. The outcomes indicate that a lower temperature level of CMQL is advantageous to producing better wear resistance and lower thermomechanical loads, and the CMQL (− 15 ºC) machining environment can remarkably improve the overall machining performance and control the surface form errors of the machined thin-wall parts. At the spindle speed of 3000 rpm, the surface roughness measured under CMQL (− 15 °C) condition is reduced by 16.53% and 23.46%, the deflection value is decreased by 54.74% and 36.99%, while the maximum thickness error is about 53.51% and 20.56% smaller in comparison to flood cooling and MQL machining. In addition, CMQL is an economical and sustainable cooling/lubrication strategy; the outcomes of this work can provide the industry with useful guidance for high-quality machining of thin-wall components.

Atomization mechanism and machinability evaluation with electrically charged nanolubricant grinding of GH4169

Nanofluid minimum quantity lubrication (NMQL), which offers excellent economic and environmental benefits, has the greatest potential to replace traditional metal grinding with fluids. However, insufficient infiltration performance, poor atomization properties, and inferior controllability are found in pneumatic atomization minimum quantity lubrication (MQL), hindering the improvement of grinding performance. Electrostatic atomization MQL (EMQL) is expected to address the coexistence of grindability and sustainability through electrical charge empowerment. Nevertheless, studies addressing the effects and mechanisms of electrically charged nanolubricants in the grinding of nickel-based superalloys remain scarce. In this study, the atomization characteristics of EMQL are experimentally investigated, and results show that the droplet volume average diameter and diameter Rosin–Rammler distribution span of EMQL decreased by 7.1 % and 40.3 %, respectively, in comparison with those of MQL. Then, a series of grinding experiments on GH4169 with different cooling conditions are conducted. Results show that compared with those for MQL grinding, the coefficients of friction for EMQL and NMQL grinding decreased by 9.35 % and 15.62 %, the specific grinding energies decreased by 16.71 % and 29.06 %, and the values of surface roughness Sa decreased by 3.04 % and 14.33 %, respectively. The optimal combination of atomization method and medium for grinding GH4169 is EMQL and nanolubricant. Sa showed a 16.12 % decrease for the surface machined via the optimal combination compared with the surface machined via flooding. Last, to support the interpretation of the grinding outcomes, the antifriction mechanisms of electrically charged nanolubricants are analyzed in combination with the wetting, infiltration, and film-formation capabilities of droplets. The findings of this work are expected to provide experimental references for the surface integrity improvement of the nickel-based superalloy grinding process.

Exploring the Impact of the Turning of AISI 4340 Steel on Tool Wear, Surface Roughness, Sound Intensity, and Power Consumption under Dry, MQL, and Nano-MQL Conditions

Optimizing input parameters not only improves production efficiency and processing quality but also plays a crucial role in the development of green manufacturing engineering practices. The aim of the present study is to conduct a comparative evaluation of the cutting performance and machinability process during the turning of AISI 4340 steel under different cooling conditions. The study analyzes cutting operations during turning using dry, minimum quantity lubrication, and nano- minimum quantity lubrication. As control parameters in the experiments, three different cooling types, cutting speeds (100, 150, 200 m/min), and feed rate (0.1, 0.15, 0.20 mm/rev) levels were applied. The experimental results show that the optimal output values are found to be Vb = 0.15 mm, Ra = 0.81µm, 88.1 dB for sound intensity and I = 4.18 A for current. Moreover, variance analysis was performed to determine the effects of input parameters on response values. Under dry, minimum quantity lubrication, and nano-minimum quantity lubrication processing conditions, parameters affecting tool wear, surface roughness, current by the motor shaft, and sound level were examined in detail, along with the chip morphology. The responses obtained were optimized according to the Taguchi S/N method. As a result of optimization, it was concluded that the optimum values for cutting conditions were nano-minimum quantity lubrication cooling and V = 100 m/min, f = 0.1 mm/rev cutting. Finally, it was observed that there was a 13% improvement in tool wear, 7% in current, 9% in surface roughness, and 8% in sound intensity compared to the standard conditions. In conclusion, it was determined that nano-minimum quantity lubrication with the lowest level of cutting and feed rate values provided the optimum results.

Tribological Analysis and Operation Issues of SiO<sub>2</sub> Nanolubricants for MQL Machining Operations

Minimum Quantity Lubrication (MQL) has been proved to be an efficient lubricant technique in machining that increases tool life, improves surface roughness, facilitates the recycling of the resulting chips, brings more sustainable practices in terms of minimum use of lubricants, and reduces the operators’ exposures to toxic particles with respect to conventional cooling practices. In order to increase the performance of MQL, nanoparticles of Al2O3, MoS2, SiO2 graphite and graphene among others have been recently introduced into MQL lubricants. This new approach, called nanoMinimum Quantity Lubrication (NMQL), has been proved to provide better thermal conductivity and lower friction coefficients during cutting, which in turns means higher cutting tool life and lower cutting forces. In this paper, a stable SiO2 -based nanolubricant was produced and characterized. A tribological analysis was conducted on SiO2 nanolubricants to be used on MQL operations. Operational issues related to particles deposition along time, loss of nanolubricant properties when it comes from the MQL system and mist generation were also analyzed.

Wear behavior of different coated tools in MQL-assisted milling of magnesium-based rare-earth alloys

One of the most important and often employed indicators for describing machinability and machining quality is tool wear. While flank wear is commonly used to gauge the extent of a worn scar, tool wear is characterized more by its shape than its size. To quantify the wear shape, more specific data concerning the wear contour is required. With this aim, the present work addresses the fundamental wear mechanisms and failure modes of several coated tools used in the mechanical milling of rare-earth magnesium (Mg-RE) alloys. Uncoated, edge-strengthened, TiAlN-coated, and diamond-coated tools were tested under dry and minimal quantity lubrication (MQL) conditions. The cutting energy flow and consumption rules governing the tool wear processes were quantified using the exergy analysis theory. The results indicate that the cutting performances of tools and the surface quality are both enhanced by the MQL through reducing adhesion wear. For the unstrengthened tool, a tool wear reduction of 55% is achieved by the MQL. While for the TiAlN-coated tool, the tool wear can be furtherly suppressed by 49%.

Novel use of cryogenic cooling conditions in improving the machining performance of Al 8011/nano-SiC composites

The inclusion of nanoparticles makes the composite not only stronger but also lighter and highly resistant towards wear among many other positive attributes. However, the high hardness and abrasive characteristics of the composites make machining a formidable task. Hence to surmount these challenges, various coolant conditions have been entailed like dry machining, flood cooling, minimum quantity lubrication (MQL), and cryogenic (cryo) CO2 cooling. This investigation encompasses the influence of diverse coolant techniques during the machining of as casted aluminium with nano silicon carbide (Al/n-SiC) composite. This study further incites the analysis of the machining temperature, surface characteristics, flank wear, and chip morphology under each coolant techniques. The outcomes of this investigation furnish a comprehensive understanding of the impact of distinct coolant environments on the machining performance of Al/n-SiC composite. The cutting temperature under cryo-CO2 was found to be lowered by 41–47%, 15–21%, and 8–12% when compared to the usage of dry, flood, and MQL, respectively. The study unveils that cryo-CO2 cooling developed the lowest machining temperature, followed by MQL, flood cooling, and dry machining. Furthermore, cryo-CO2 cooling and MQL exhibited the best outcome in terms of flank wear and surface characteristics. The verdicts of this investigation suggest the use of cryo-CO2 cooling and MQL makes eloquent improvement in the machining performances of Al/n-SiC composites.

Nanofluids Minimal Quantity Lubrication Machining: From Mechanisms to Application

Minimizing the negative effects of the manufacturing process on the environment, employees, and costs while maintaining machining accuracy has long been a pursuit of the manufacturing industry. Currently, the nanofluid minimum quantity lubrication (NMQL) used in cutting and grinding has been studied as a useful technique for enhancing machinability and empowering sustainability. Previous reviews have concluded the beneficial effects of NMQL on the machining process and the factors affecting them, including nanofluid volume fraction and nanoparticle species. Nevertheless, the summary of the machining mechanism and performance evaluation of NMQL in processing different materials is deficient, which limits preparation of process specifications and popularity in factories. To fill this gap, this paper concentrates on the comprehensive assessment of processability based on tribological, thermal, and machined surface quality aspects for nanofluids. The present work attempts to reveal the mechanism of nanofluids in processing different materials from the viewpoint of nanofluids’ physicochemical properties and atomization performance. Firstly, the present study contrasts the distinctions in structure and functional mechanisms between different types of base fluids and nanoparticle molecules, providing a comprehensive and quantitative comparative assessment for the preparation of nanofluids. Secondly, this paper reviews the factors and theoretical models that affect the stability and various thermophysical properties of nanofluids, revealing that nanoparticles endow nanofluids with unique lubrication and heat transfer mechanisms. Finally, the mapping relationship between the parameters of nanofluids and material cutting performance has been analyzed, providing theoretical guidance and technical support for the industrial application and scientific research of nanofluids.

Evaluation of tribological interactions and machinability of Ti6Al4V alloy during finish turning under different cooling conditions

The titanium alloy Ti6Al4V has several applications and is considered as a difficult-to-machine material. This study evaluates some tribological interactions in finish turning of Ti6Al4V titanium alloy, including the tool wear, and coefficient of friction in tool-chip interface. Subsequently, the machinability of Ti6Al4V titanium alloy has been investigated, considering the chip geometry, chip thickness ratio, as well as changes in the total cutting force components. The turning process was carried out over a wide range of the feed rate (f) and depths of cut (ap) using hard carbide, GC1115 grade, inserts with double-layer PVD coating. The finish turning tests were conducted under the dry, flood, and MQL (minimum quantity lubrication) cutting conditions. It was found that favorable chip shapes (arc loose) were obtained in the range ap = 0.9–1.2 mm and f = 0.25–0.4 mm/rev. Increasing the f clearly affects the formation of a serrated chip. In addition, the intensity of tool wear, as well as the variations of cutting forces and chip thickness ratios were strongly affected by the applied cooling/lubricating condition. Compared to wet conditions, the Kh values decrease by ∼22 % with dry machining and by ∼12 % with MQL. Compared to wet conditions, for dry machining the cutting forces decrease to 70 % and with MQL to 8 %. The cumulative wear rate under dry machining increases by 18 % compared to wet conditions, and with MQL reduces by 19 %.

Comparison of single nozzle and dual nozzle MQL performance in hardened steel turning: A case study

This study focused on comparing the machining output performance of single and dual jet nozzle assisted MQL (Minimum Quantity Lubrication) in CNC hard turning. Two case studies were conducted using different hardened steels and cutting tools. The cutting parameters including feed rate (0.1 mm/rev), cutting speed (60 m/min) and depth of cut (0.1 mm) were maintained constant. In the first case study, AISI 4340 hardened steel workpiece and CVD-coated carbide cutting tool were used. The results showed that the dual nozzle MQL system achieved lower tool flank wear (30.54 %), cutting power (11.33 %), surface roughness (24.59 %), cutting temperature (22.36 %), and cutting sound (2.35 %) compared to the single nozzle system. The second case study used AISI D2 steel workpiece and PVD-coated carbide tool, and similar findings were observed. Cutting power observed during hard turning operations in a dual nozzle MQL environment was 0.360 kW for AISI 4340 Steel and 0.386 kW for AISI D2 Steel, respectively, which is very low in terms of hard turning concerns. Dual Nozzle Overall, the dual nozzle MQL system consistently demonstrated more efficient machining, regardless of the variations in tool material, workpiece material, and hardness. Therefore, it is suggested for further research in machining applications in the future.

Carbon nano dots mixed rice bran oil as a cutting fluid for enhanced lubrication/cooling in milling of additively manufactured 316 stainless steel

Nanofluids, which have improved thermal conductivity compared to regular lubricants, can assist in the dissipation of heat while cutting materials. A colloidal suspension can be formed by dispersing nanoparticles within a base fluid. Their high thermal conductivity and viscosity make them a promising heat transfer fluid option; by using nano-additives, their cooling and lubricating capabilities may be further improved. Recently, carbon nanodots have grabbed the attention due to their many desirable characteristics, including their high solubility, chemical inertness, and low toxicity. Therefore, in this perspective, the thermophysical properties of rice bran oil enriched with carbon nanodots and their considerable impact on the machinability of 316 stainless steel produced additively has been examined. The different wt.% (0–1.25) of carbon nanodots are dispersed in rice bran oil to test the wettability, thermal conductivity, and dynamic viscosity. After that, milling tests are conducted under dry, flood, minimum quantity lubrication, and nano-minimum quantity lubrication conditions. The findings admit that the inclusion of nanoparticles in rice bran oil at 1 wt.% results in lower contact angle, higher thermal conductivity, and higher viscosity. In addition, the employment of nanoparticles in minimum quantity lubrication reduced the roughness by 60–63 %, 40–43 %, and 22–25 % in relation to dry, flood, and MQL conditions, respectively. The reduction in roughness has a direct influence on tool wear.

An Experimental Investigation of the Effects of Dressing and Grinding Parameters on Sustainable Grinding of Inconel 738 Used for Automated Manufacturing

The significant effect of the dressing process on the surface of the grinding wheel (GW) and the need to provide an optimal dressing condition are the requirements of reduction machining time and energy consumption in the sustainable grinding process. In this study, for the first time, the results of changes in the parameters of the dressing process and changes in the topography of the grinding surface on the surface roughness of the Inconel 738 have been presented using single-edge and four-edge diamond dressers. The use of minimum quantity lubrication (MQL) and wet condition are other variables in this study to reduce the consumption of cutting fluid and prevent its destructive effects on the environment. The results indicate that the MQL technique increases the grinding performance of Inconel 738 by reducing ground workpiece surface roughness and decreasing the coolant–lubricant consumption comparing to the conventional wet grinding process. Additionally, it has been found from the experimental results that applying a single-edge dresser generates finer topography on the grinding wheel and, consequently, has a better surface finish in the grinding process compared to the multipoint diamond dressing tool with the same dressing and grinding parameters. In other words, increasing the dressing feed rate during dressing of the grinding wheel using a multipoint dresser makes a finer wheel surface topography and as a result decreases the surface roughness of the ground workpiece compared to a single-edge dresser. With multipoint diamond tools, the grinding performance during the life of the dressing tool also tends to remain more consistent, which is a definite advantage in automated production. Therefore, application of a multipoint dresser leads to a reduction in dressing time and increased production capability.

Soft computing for sustainable drilling of AISI 316L stainless steel under formulated neem oil minimum quantity lubrication condition

Soft computing for sustainable drilling of AISI 316L stainless steel under formulated neem oil minimum quantity lubrication condition

The analysis of grid independence study in continuous disperse of MQL delivery system

A sustainable cutting method of Minimum Quantity Lubricant (MQL) was introduced to promote lubrication effect and improve machinability. However, its performances are very dependent on the effectiveness of its mist to penetrate deep into the cutting zone. Optimizing the MQL system requires massive experimental work that increases cost and time. Therefore, this study conducts Computational Fluid Dynamic (CFD) analysis using ANSYS Fluent and focuses on the grid independence study in dispersed-continuous phase of MQL delivery system. The main aim is to identify the best mesh model that influences the accuracy of the CFD model. The analysis proposed two different unstructured grid cell elements of quadrilateral and triangular that were only applicable for 2-dimensional fluid flow in CFD. The unstructured grid was controlled with three different mesh quality factors such as Relevance Center, Smoothing, and Span Angle Center at coarse /low, medium, and fine /high. The results showed that the best mesh quality for quadrilateral was at 60,000 nodes number and coarse mesh, whereas the triangular was at 90,000 nodes number and coarse mesh. Both combinations resulted the most consistent and reliable result when compared with past studies. However, this study decided to choose quadrilateral cell element with 60,000 nodes number and coarse mesh as it is considered to be sufficient to provide accurate and reliable result as well as practical in terms of computational time for the MQL model in CFD analysis.

A review on minimum quantity lubrication (MQL) assisted machining processes using mono and hybrid nanofluids

PurposeBecause many cutting fluids contain hazardous chemical constituents, industries and researchers are looking for alternative methods to reduce the consumption of cutting fluids in machining operations due to growing awareness of ecological and health issues, government strict environmental regulations and economic pressures. Therefore, the purpose of this study is to raise awareness of the minimum quantity lubrication (MQL) technique as a potential substitute for environmental restricted wet (flooded) machining situations.Design/methodology/approachThe methodology adopted for conducting a review in this study includes four sections: establishment of MQL technique and review of MQL machining performance comparison with dry and wet (flooded) environments; analysis of the past literature to examine MQL turning performance under mono nanofluids (M-NF); MQL turning performance evaluation under hybrid nanofluids (H-NF); and MQL milling, drilling and grinding performance assessment under M-NF and H-NF.FindingsFrom the extensive review, it has been found that MQL results in lower cutting zone temperature, reduction in cutting forces, enhanced tool life and better machined surface quality compared to dry and wet cutting conditions. Also, MQL under H-NF discloses notably improved tribo-performance due to the synergistic effect caused by the physical encapsulation of spherical nanoparticles between the nanosheets of lamellar structured nanoparticles when compared with M-NF. The findings of this study recommend that MQL with nanofluids can replace dry and flood lubrication conditions for superior machining performance.Practical implicationsMachining under the MQL regime provides a dry, clean, healthy and pollution-free working area, thereby resulting the machining of materials green and environmentally friendly.Originality/valueThis paper describes the suitability of MQL for different machining operations using M-NF and H-NF.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0131/

Minimum Quantity Lubrication Jet Noise: Passive Control.

Jet noise is a common problem in minimum quantity lubrication (MQL) technology. This should be given great attention because of its serious impacts on the physical and mental health of the operators. In this study, a micro-grooved nozzle is proposed based on the noise reduction concept of biological micro-grooves. The flow field and acoustic characteristics of an original nozzle and a micro-grooved nozzle were investigated numerically to help better understand the noise reduction mechanism. The reasons for noise generation and the effects of the length (L), width (W) and depth (δ) of the micro-grooves on noise reduction were analyzed. It was found that jet noise is generated by the large-scale vortex ring structure and the pressure fluctuations caused by its motion. The overall sound pressure level (OASPL) decreased with the increases in W and δ, and increased with the increase in L. Among of them, δ has the greatest effect on noise reduction. The maximum noise reduction achieved was 6.66 dB, as verified by the OASPL test. Finally, the noise reduction mechanism was discussed in terms of the flow field, vorticity and the frequency characteristics. Micro-grooves can enhance the mixing of airflow inside the nozzle and accelerate the process of large-scale vortices breaking into smaller-scale vortices. It also reduces the sound pressure level (SPL) of middle frequencies, as well as the SPL of high frequencies on specific angles.

EFFECTS OF VIBRATION CONDITIONS ON MACHINABILITY OF AISI 52100 BEARING STEEL

This study focused on determining the effects of the cooling condition in the conventional and ultrasonic-assisted turning of AISI 52100 steel. AISI 52100 steel has been widely used in the bearing, mold, and automotive industries because of its superior wear resistance and mechanical properties. However, its high wear resistance caused poor machinability in conventional machining methods. Low surface quality, rapid tool wear, high cutting temperature, and high cutting force are the main difficulties in the conventional machining of AISI 52100 steel. On the other hand, ultrasonic-assisted machining has become widely used in the past decades for the machining of materials that have low machinability in conventional methods. Conventional turning and ultrasonic-assisted turning were selected as machining methods. Ultrasonic-assisted turning experiments were conducted under 20 and 30 kHz vibration frequencies. Cubic Boron Nitride (CBN) cutting tools were used in machining experiments. In machining operations 50, 100, and 150 m/min cutting speeds were selected, and feed rate (0.1 mm/rev) and depth of cut (0.5 mm) were kept constant in experiments. Minimum quantity lubrication technique which used 1% Al2O3 nanoparticle additives cutting fluid and dry cooling methods were used. CBN insert was used as a cutting tool. The effects of cutting speed, cutting method, and cooling condition on surface quality, cutting force, cutting zone temperature, and cutting tool wear were studied experimentally. Analysis of Variance (ANOVA) was carried out to determine the significance of the effects of input variables on process outputs. As a result of this study, it is determined that combined UAT and nanoMQL have significant effects on the process outputs.

Significance of Temperature-Dependent Density on Dissipative and Reactive Flows of Nanofluid along Magnetically Driven Sheet and Applications in Machining and Lubrications

Nanofluid lubrication and machining are challenging and significant tasks in manufacturing industries that are used to control the removal of a material from a surface by using a cutting tool. The introduction of a nanofluid to the cutting zone provides cooling, lubricating, and chip-cleaning benefits that improve machining productivity. A nanofluid is a cutting fluid that is able to remove excessive friction and heat generation. Chemical reactions and temperature-dependent density are essential in the thermal behavior of a nanofluid. The present study presents a careful inspection of the chemical reactions, temperature-dependent density, viscous dissipation, and thermophoresis during the heat and mass transfer of a nanofluid along a magnetically driven sheet. The physical attitude of viscous dissipation and the chemical reaction improvement rate in magneto-nanofluid flow is the primary focus of the present research. By applying the proper transformation, nonlinear partial differential expressions are introduced to the structure of the ordinary differential framework. The flow equations are simplified into nonlinear differential equations, and these equations are then computationally resolved via an efficient computational technique known as the Keller box technique. Flow factors like the Eckert number, reaction rate, density parameter, magnetic force parameter, thermophoretic number, buoyancy number, and Prandtl parameter governing the velocity, temperature distribution, and concentration distribution are evaluated prominently via tables and graphs. The novelty of the current study is in computing a heat transfer assessment of the magneto-nanofluid flow with chemical reactions and temperature-dependent density to remove excessive friction and heating in cutting zones. Nanofluids play significant roles in minimum quantity lubrication (MQL), enhanced oil recovery (EOR), drilling, brake oil, engine oil, water-miscible cutting fluids, cryogenic cutting fluids, controlled friction between tools and chips and tools and work, and conventional flood cooling during machining processes.