Evaluation of the impact of ecofriendly lubrication techniques on the surface roughness during AISI 8640 steel turning

Slot milling of titanium alloy with hexagonal boron nitride and minimum quantity lubrication and multi-objective process optimization for energy efficiency

Study on surface integrity and fatigue performance of FeCoCrNiAl₀.₆ high-entropy alloy based on thermo-mechanical coordinated control

The effect of vibration and cutting zone temperature on surface roughness and tool wear in eco-friendly MQL turning of AISI D2

The hardening of legislation in favor of socio-environmental preservation and the sustainable focus of industry are changing the current manufacturing methods, among which is grinding. This abrasion machining technique aims to produce parts with excellent surface finish and high geometric precision. On the other hand, the multiple sharp edges of the abrasive grains that make up the grinding wheel simultaneously deform and shear the workpiece surface material, which releases a lot of energy in the form of heat. In this context, to soften the damage caused by the high temperatures, cutting fluids are applied to lubricate and refrigerate the tool/workpiece interface during the grinding process. However, the use of these fluids is damaging to people’s health and carries a high cost for disposal, given their potential to impact the biosphere. In this sense, the society allied with the researchers seeks alternative methods of lubri-refrigeration, among them, the minimum quantity lubrication (MQL), which applies a small quantity of fluid to the cutting zone through a flow of compressed air. However, the excessive increase of machining temperatures and the intensification of the grinding wheel clogging are significant drawbacks of this technique. Thus, to mitigate these problems, this work seeks to evaluate the traditional MQL application, MQL with cooled air (MQL+CA), and assisted by a wheel cleaning jet (MQL+WCJ), comparing them with the conventional method with abundant fluid, in the external cylindrical plunge grinding of the AISI 4340 steel using an aluminum oxide grinding wheel. The output parameters used to assess the efficiency of the techniques were surface roughness, roundness error, diametrical wheel wear, grinding power, tangential cutting force, specific grinding energy, and microhardness. The machined surfaces were evaluated through optical and scanning electron microscopies to verify possible thermal damages and microstructural alterations, and optical microscopy images of the grinding wheel cutting surface were assessed to ascertain the occurrence of the wheel clogging phenomenon. The results of the tests showed that the conventional method produced the best results in all analyzed parameters. Besides, MQL+WCJ and MQL+CA outperformed all the results obtained with traditional MQL, which revealed the improvement obtained with these eco-friendly techniques and their applicability in the industry. Moreover, the application of the MQL+WCJ provided the closest results in comparison with the conventional method, proving to be superior to the MQL+CA.

Manufacturing cost and productivity in machining systems can be significantly affected by the optimized input sources. Further, metal cutting industries have shown curiosity toward surface textured tools due to gain in productivity. In this context, new textured tools were developed and machinability studies were carried out on AISI 304 material under eco-friendly technique namely Minimum Quantity Lubrication (MQL) with so developed tools. The novel textured tools were fabricated by making circular micro pit holes on the rake face of the tungsten carbide tool using laser technology. In this work, a new weighted gray relation analysis (WGRA) integrated Jaya algorithm is proposed to determine the best cutting parameters. From the result, it is found that 54%, 7% respective reduction in surface roughness (Ra) and tool wear (Vb) and 27% increment in material removal rate (MRR) at the optimum conditions determined by the proposed optimization technique. It is concluded that the proposed work meets the environmental sustainability requirements and improved the turning process performance.

Ti-6Al-4V is a titanium-based alloy that is widely used in a diverse range of applications, especially in industries such as biomedical and aerospace. Several lubricooling techniques have been introduced to enhance the machinability of these materials. Among them, environmentally friendly strategies are gaining in importance, with sustainability trends rising in manufacturing. The present research investigates the effect of two eco-friendly lubricooling techniques (minimum quantity lubrication and cryogenic cooling), along with other cutting parameters (cutting speed and feed per tooth), on the surface roughness and microhardness of the machined surfaces, which are identified as one of the most frequently implemented indicators of surface integrity in the ball-end milling of the Ti-6Al-4V alloy. In addition, the total electrical energy consumption of the machine tools under different cooling/lubrication conditions was also analyzed. The results obtained showed that cryogenic cooling enhanced milling performance as compared to MQL. Moreover, a multi-objective parameter optimization model integrating the machining responses (surface roughness, microhardness, energy consumption, and productivity) and sustainability metrics (environmental impact, operator’s health and safety, and waste management) was introduced. It was found that cryogenic cooling outperformed the MQL method in terms of both machining performance and environmental impact. An analysis of variance (ANOVA) was carried out to evaluate the significance of each process parameter on the multiple performance index. The results indicate that feed per tooth, cooling method, and cutting speed were significant, with respective contributions of 39.4%, 36.8%, and 22.9%. Finally, the optimal parameter setting was verified through a confirmation test and the results reveal that an improvement was observed in the machining responses and multiple performance index.

Proper cutting parameters are needed to produce lower surface roughness of titanium alloy machined material. The high temperature in the cutting zone is always happened due to high friction between the tool and the workpiece and will cause dimensional error and poor surface roughness. Therefore, the main objectives of this research were to investigate and compare the surface roughness and material removal rate (MRR) of Ti-6AL-4 V alloy under the dry and minimum quantity lubrication (MQL) technique. The effect of cutting parameters towards surface roughness was investigated and the optimum cutting parameters was studied to obtain lower surface roughness and higher MRR. From ANOVA, spindle speed has been identified as the most significant parameter that affects the surface roughness and MRR. In t his paper, the optimum cutting parameters that give the low surface roughness and high MRR was 1500 rpm (spindle speed), 0.4 mm/tooth (feed per tooth), and 0.4 mm (depth of cut). From this study, it can be concluded that in this milling of Ti-6Al-4 V alloy, higher spindle speed, feed per tooth, and depth of cut are preferable to achieve the better surface quality of Ti-6Al-4 V alloy.

Inconel 718 is a nickel-based alloy commonly used due to its excellent mechanical properties at high temperatures and its elevated corrosion resistance. This material however is difficult to machine due to the high temperature generated during machining, which requires efficient lubrication system. Minimum quantity lubrication (MQL) technique is a more efficient and a more environmentally friendly alternative to conventional flooding lubrication technique. The efficiency and efficacy of this lubrication technique can be further enhanced by adding nano particles and surfactant into the base lubricant. There are currently limited number of studies on the application of minimum quantity lubrication (MQL) technique using nanolubricant with added surfactant in the machining of hard-to-machine materials such as Inconel 718. Consequently, this paper aims to optimize the cutting parameters for surface roughness under minimum quantity lubrication (MQL) condition using surfactant-added Al2O3 nanolubricant during the turning of Inconel 718. The effects of cutting speed, depth of cut and feed rate and their two-way interactions on surface roughness are investigated on the basis of the standard Taguchi’s L9 orthogonal array (OA) design of experiment and the results are assessed using analysis of variance (ANOVA) and signal to noise (S/N) ratio methods to determine the optimal cutting parameter settings as well as the level of significance of the cutting parameters. The optimal surface finish can be observed at the cutting speed of 70 m/min, depth of cut of 0.05 mm and feed rate of 0.05 mm/rev with feed rate being the most significant factor to affect surface finish. Through this study, the application of minimum quantity lubrication (MQL) technique using surfactant-added Al2O3 nanolubricant, has been shown to produce desirable surface finish quality on Inconel 718 with additional economic and ecological benefits.

In this study, we investigate the tribological influence of incorporating nano MoS 2 particles into the MQL environment during the turning of Aluminium Alloy AA2024. In nano-minimum quantity lubrication (nano-MQL) technique, a very tiny amount of high-performance lubricant is applied straight to the cutting zone. Generally, the lubricant is applied in nanodroplets, which are substantially smaller than standard minimum quantity lubrication (MQL) droplets. Achieving a desired surface roughness is crucial in machining operations. The experiment explores the influence of various machining parameters on surface roughness (R a ). In addition, four machine learning models are used to estimate the surface roughness and compare the experimental value to the anticipated values. For the coefficient of determination (R 2 ), mean absolute percentage error (MAPE), and mean square error (MSE) were all used to assess how accurate the projected values were. Machine learning models Gradient boosting, linear regression and Random Forest has estimated the following R-squared values 1.000, 0.999 and 0.959 respectively. Experimental results reveal that nano-MQL significantly improves surface quality and tool wear, achieving a surface roughness of 0.8399 µm and 0.024 mm tool wear at 339.12 m/min cutting speed, 0.1 mm/rev feed rate, 0.25 mm depth of cut. The average surface roughness decreases by 28% when compared with dry cutting environment.

Evaluation of the impact of ecofriendly lubrication techniques on the surface roughness during AISI 8640 steel turning

The emerging grave consequences of conventional coolants on health, ecology and product quality, have pushed the scientific research to explore eco-friendly lubrication technique. Electrostatic minimum quantity lubrication (EMQL) has been underscored as a burgeoning technology to cut-down bete noire impacts in machining. This research confers the adoption of a negatively charged cold mist of air-castor oil employed in turning of aluminium-6061T6 material by varying the cutting conditions, as per experimental designed through response surface methodology (RSM). For comprehensive sagacity, a range of cutting speed, feed, depth of cut and EMQL-flow rate were considered. Material removal rate, tool life, surface roughness and power consumption of machine tool were adopted as performance measures. To satisfy multi-criterion simultaneously, RSM-based grey relational analysis (GRA) was employed for multi-objective optimisation. Highest proportion of grey relational grade (GRG) as a single desideratum response function, provided a trade-off between performance measures with 15.56% improvement in GRG.

Investigation of different cutting conditions in the machining of steel — Towards cleaner production

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.

We developed an isocyanate group containing quaternary ammonium salt (IQAS) as a potential antimicrobial finishing agent that can be stored in a high purity form for more than a year in dry environments to permit convenient transportation and storage. Additionally, we report a facile and eco-friendly finishing technique to fabricate durable antimicrobial cotton fabrics using IQAS as an antimicrobial finishing agent by a dipping–padding–drying process. IQAS was bound onto the surface of cotton fabrics by a covalent bond to obtain a cotton fabric with excellent bactericidal activity, tearing strength, breaking elongation, bending rigidity, water vapor permeability, surface roughness and smoothness. The antimicrobial rates of these fabrics reached 92.2% and 98.5% against gram-negative bacterium Escherichia coli and gram-positive bacterium Staphylococcus aureus, respectively, even after 50 laundering cycles. These values are much higher than the reference antimicrobial rates of AAA class antimicrobial fabrics, as well as those of conventionally finished cotton fabrics, indicating that the IQAS finished cotton fabrics maintained excellent antimicrobial activity even after long-term repeated launderings. Moreover, the results indicate that the IQAS-treated cotton fabrics could improve the breaking strength (increased by 13.5% in the warp direction and 20.3% in the weft direction), the bursting strength (increased by 11.9%), the air permeability (increased by 12.6%) and the hydrophilicity compared to untreated cotton fabrics. Additionally, our non-leaching antimicrobial cotton fabrics treated with IQAS were non-toxic and showed no skin stimulation. Therefore, IQAS and the antimicrobial finishing technique reported here have great potential applications in antimicrobial fabrics used in hospitals, hotels and other susceptible situations. An isocyanate group containing quaternary ammonium salt that permits convenient transportation and storage was developed as a potential antimicrobial finishing agent to fabricate excellent antimicrobial cotton fabrics with well-preserved physical properties and security using a dipping–padding–drying process.

In the current scenario, the demand for eco-friendly manufacturing techniques has been raising due to stringent rules on utilization of chemical coolants. Minimum Quantity Lubrication (MQL) cooling and surface textured tool techniques support eco-friendliness. However, the machining performance of textured tools under MQL technique significantly depends on geometry of the textured design and its coolant storage capabilities during machining operation. In this context, in the current work, new dual textured design cutting tools were fabricated and assessed for its performance in turning of AISI304 material under MQL conditions. Experiments were conducted using orthogonal array design with both textured and untextured tools. Results indicated that textured tools demonstrated superior turning performance in terms of cutting temperature (T), tool rake wear (Vr), tool flank wear (Vb), and surface roughness (Ra), with maximum reductions of 48%, 24%, 45%, and 28%, respectively, than non-textured tools. Further, higher BUE and edge chipping out mechanisms were pragmatic in conventional tools. Furthermore, it was revealed that derivative cutting mechanism and effective cooling are accountable for paramount results in textured tools. The proposed combination of machining technique in the current study cares about environmental cleanness along with process improvement and contributes to a few of the sustainable development goals.