Showing papers on "Cutting fluid published in 2023"

Machinability Investigations based on Tool Wear, Surface Roughness, Cutting Temperature, Chip Morphology and Material Removal Rate during Dry and MQL-Assisted Milling of Nimax Mold Steel

Abstract: Using cutting fluids is considered in industrial applications and academia due to their increased influence over many aspects such as machinability, sustainability and manufacturing costs. This paper addresses the machinability perspective by examining indicators such as roughness, cutting temperature, tool wear and chip morphology during the milling of mold steel. A special type of steel is Nimaxm which is a difficult-to-cut material because of its high strength, toughness, hardness and wear resistance. Since mold steels have the reverse geometry of the components produced by this technology, their surface quality and dimensional accuracy are highly important. Therefore, two different strategies, i.e., dry and minimum quantity lubrication (MQL), were chosen to conduct an in-depth analysis of the milling performance during cutting at different cutting speeds, feed rates and cutting depths. Without exception, MQL technology showed a better performance than the dry condition in obtaining better surface roughnesses under different cutting parameters. Despite that only a small improvement was achieved in terms of cutting temperature, MQL was found to be successful in protecting the cutting tool from excessive amounts of wear and chips. This paper is anticipated to be a guide for manufacturers and researchers in the area of mold steels by presenting an analysis of the capabilities of sustainable machining methods.

State-of-the-Art in Sustainable Machining of Different Materials Using Nano Minimum Quality Lubrication (NMQL)

Abstract: In the manufacturing industry, during machining, the conventional cutting fluid plays a vital role; however, extravagant use of cutting fluids due to its disposal affects the environment badly. Nowadays, due to these advantages of conventional cutting fluids, alternative methods of conventional cutting fluids or alternative methods are preferred. One of the most preferred methods may be the minimum quantity lubrication technique with conventional or nanoparticle-enriched cutting fluids. The present paper has a compilation of the investigations based on MQL application in different machining processes such as turning, milling, grinding, and drilling. The machining also involves hard-to-machine alloys. The paper discusses cryogenic MQL in brief and opens the domain for work in future. The purpose of this paper is to provide a quick reference for researchers working on the practical use of MQL lubricants with nanopowders dissolved and their application in machining for different materials.

Machinability Assessment of Hybrid Nano Cutting Oil for Minimum Quantity Lubrication (MQL) in Hard Turning of 90CrSi Steel

Abstract: Friction and very high temperature are still the major challenges in hard machining technology and they greatly affect cutting efficiency. The application of the MQL (minimum quantity lubrication) method, using nanoparticles in order to improve the cooling lubrication performance of the base cutting oil, has proven to be a promising solution. Hence, this work aimed to investigate the effectiveness of Al2O3/MoS2 hybrid nanofluid and Al2O3 and MoS2 mono nanofluids in the hard turning of 90CrSi steel (60–62 HRC) under an MQL environment. The Box-Behnken experimental design was used for three input variables, including nanoparticle concentration, air pressure, and air flow rate. Their influences on surface roughness and cutting forces were studied. According to the obtained results, it was shown that the application of hybrid nano cutting oils in MQL contributes to achieving better hard machining performance than the use of mono nanofluids. In particular, a lower cutting temperature is reported and the values of surface roughness Ra, back force Fp, and cutting force Fc were smaller and more stable under Al2O3/MoS2 hybrid nanofluid MQL than those under Al2O3 and MoS2 mono nanofluid MQL due to an improvement in cooling lubrication characteristics. Thus, this work provides a novel approach to study hybrid nanofluids for MQL hard machining.

Helical Milling of CFRP/Ti6Al4V Stacks Using Nano Fluid Based Minimum Quantity Lubrication (NF-MQL): Investigations on Process Performance and Hole Integrity

Abstract: The structural components in the aeronautical industry require CFRP/Ti6Al4V stacks to be processed together, which results in poor hole integrity due to the thermal properties of the materials and challenges related to processability. These challenges include quality variation of the machined holes because of the limitations in process properties. Therefore, a novel solution through helical milling is investigated in the study using nano fluid based minimum quantity lubrication (NF-MQL). The analysis of variance shows, for Ti6Al4V, eccentricity (PCR = 28.56%), spindle speed (Ti) (PCR = 42.84%), and tangential feed (PCR = 8.61%), and for CFRP, tangential feed (PCR = 40.16%), spindle speed (PCR = 28.75%), and eccentricity (PCR = 8.41%) are the most significant parameters for diametric error. Further on, the rise in the circularity error is observed because of prolonged tool engagement at a higher value of tangential feed. Moreover, the surface roughness of Ti was reduced with an increasing percentage of MoS2 in the lubricant. The spindle speed (37.37%) and lubricant (45.76%) have a potential influence on the processing temperature, as evident in the analysis of variance. Similarly, spindle speed Ti (61.16%), tangential feed (23.37%), and lubrication (11.32%) controlled flank wear, which is critical to tool life. Moreover, the concentration of MoS2 decreased edge wear from ~105 µm (0.5% concentration) to ~70 µm (1% concentration). Thorough analyses on process performance in terms of hole accuracy, surface roughness, processing temperature, and tool wear are carried out based on the physical science of the process for cleaner production. The NF-MQL has significantly improved process performance and hole integrity.

Dry and MQL Milling of AISI 1045 Steel with Vegetable and Mineral-Based Fluids

Abstract: The use of mineral-based cutting fluids in machining has the drawback of affecting the environment and industries are under pressures to reduce its use in favor of cleaner productions. In this regard, the vegetal-based cutting fluids can be a superior alternative, provided they improve the technical outcomes. In the milling process, dry cutting is commonly performed, however, the application of cutting fluids using the minimum quantity of lubricant (MQL) method has proven advantageous when compared with dry machining. Furthermore, in the midst of the availability of several cutting fluids in the market, the testing of their individual performance can ascertain their potential and effectiveness for a particular application. This study examined the performances of two vegetable-based and one mineral-based oils applied by the MQL method, followed by their comparison with dry cutting amid end milling of AISI 1045 steel with TiAlN-coated cemented carbide inserts. The cutting temperature, machining forces, power consumption, workpiece surface roughness, tool life, and tool wear mechanisms were chosen as the output parameters. The experiments were conducted using two cutting speeds (150 and 200 m/min) and feed rates (0.07 and 0.14 mm/tooth), and constant axial (1 mm) and radial depths of the cut (25 mm). The temperature was measured using a K-type thermocouple soldered to the part and an infrared camera. The power was monitored with a Fluke 435 energy analyzer, and the machining force components with a Kistler dynamometer. The worn inserts were inspected under a scanning electron microscope (SEM) to analyze the tool wear mechanism. The MQL-assisted application of the cutting fluids notably lowered the cutting temperature and increased the tools’ lives. However, the cutting fluids did not reflect any significant effect on the machining force, power consumption, or surface roughness. Among all the analyzed cutting conditions, the abrasive wear mechanism dominated, damaging the cutting edges, flank, and rake surfaces of the cutting tools. In addition, adhesive and diffusion wear mechanisms were also observed.

Review on the effect of surface textured tool in the field of machining

Abstract: A variety of simple and complex components made of metal, as well as non-metals, can be fabricated by machining. Generally, the machining process produces enormous heat at the metal cutting interface. Coolants are more often used to lessen the amount of heat generated during machining. However, it has been found that cutting fluid produces environmental risks and health risks to the operators such as skin cancer, respiratory diseases, cough, etc. and it also increases machining costs. Therefore, several researchers are working in this field to mitigate these problems without compromising the quality of machined parts produced. Manufacturing processes should be optimised without affecting the environment. Researchers are shifting towards environmental sustainability and adopting various novel machining processes like dry machining, MQL, cryogenic machining, etc. thereby curtailing the usage of cutting fluid up to certain extent. Micro-nano textured surfaces eventually reduces wear, and it will also help in reducing the cutting temperature through effective lubrication and cooling. This article aims to provide comprehensive information on different prospects of surface textured cutting tools in the field of machining.

Experimental investigation of the low-temperature oil-on-water cooling and lubrication in turning the hardened AISI D2 steel

Abstract: In this paper, the influence of the cutting speed, feed, and the depth of cut on the cutting force, surface roughness, cutting temperature, and tool wear were experimentally investigated under the low-temperature oil-on-water (LTOoW) cooling and lubrication condition in turning the hardened tool steel AISI D2 (60 ± 1HRC) with the PCBN cutting tool. The results showed that the three-component cutting forces are FY > FZ > FX. The influence of the cutting speed on the cutting temperature is slightly more visible compared to the feed and depth of cut. In this experiment, a satisfactory surface roughness value of 0.54 µm can be obtained, gaining the effect of the turning instead of the grinding. The flank wear values of the PCBN tool are 142 µm and 148 µm at the cutting speeds of 55 and 140 m/min, respectively; however, the flank wear abruptly increases to 668 µm at a 495 m/min, which has a very serious impact on the tool life. The abrasive wear is considered to be a predominant wear mechanism on the flank wear of the PCBN tool. The rake face is dominated by crater wear due to the high temperature, high pressure, high stress, and high friction at the chip-tool interface. Compared with dry hard turning (DHT) condition, the lower surface roughness value, lower cutting temperature, and longer tool life can be obtained at LTOoW.

Cutting performance of a tool with continuous lubrication of atomized cutting fluid at the tool-chip interface

Abstract: To improve the tool lubrication performance and reduce the use of cutting fluid as much as possible, a new type of tool with continuous lubrication on the tool-chip contact interface has been fabricated. The atomized cutting fluid can be directly delivered to the tool-chip contact interface through the inner microchannel. Experiments were conducted on the new lubrication method, dry cutting, and traditional MQL cutting of 45 steel. The three-dimensional cutting forces and the cutting temperatures were measured. The wear surface of the rake face was analyzed through SEM micromorphology and EDS element detection. The results showed that the main cutting force of the tool with continuous lubrication at the tool-chip interface decreased by 14.5% and 5.9% compared with the conventional tools of dry cutting and MQL cutting. Moreover, the friction coefficient decreased by 14.2% and 9.8%, the length of the tool-chip contact interface decreased by 35.4% and 19.1%, and the amount of cutting fluid was only 1/10 of that in MQL cutting. The new lubrication method had better cutting fluid penetration and lubrication film formation performance than the traditional MQL method on the tool-chip interface. Furthermore, the surface wear of the new lubrication method was significantly reduced, and the main wear form of the new lubrication method was adhesive wear.

Evaluation of Nano Fluids with Minimum Quantity Lubrication in Turning of Ni-Base Superalloy UDIMET 720

Abstract: This article focuses on turning superalloy Udimet 720, which is difficult to work with, using different coolant/lubricant methods. The study includes delivering Graphene and Multi-Walled Carbon Nanotubes nanopowders homogeneously dispersed in vegetable oil to the cutting area with the minimum quantity lubrication (MQL) method. Experiments at different cutting speeds and feed rates were repeated in four different cutting environments. Compared to dry turning, the cutting zone temperature of the cutting fluid delivered to the cutting zone by MQL methods decreased. In addition, thanks to the nanopowders, it formed an oil film by better penetrating the cutting tool-chip interface and reducing the cutting tool’s wear. With the reduced cutting tool wear, the cutting tool could maintain its form for a longer period of time, so better quality surfaces were obtained on the workpiece surface. As a result of the study, it was found that cutting zone temperature improved by 30%, tool wear by 51.8% and surface roughness by 43.9%.

Water vapor cutting fluid assisted productive machining of Inconel 718

Abstract: High-speed turning of Inconel 718 has been assessed with coated carbide tooling incorporating the minutely explored eco-friendly cutting fluid as water vapour. Effect of total seven parameters, viz. nozzle diameter, stand-off distance, pressure, flowrate, cutting speed, feedrate and depth of cut, has been explored for the resulting machined surface quality in terms of surface roughness and surface alterations; additionally introspection of chip reduction ratio has been done to evaluate cooling/lubrication mechanics of water vapour at tool-work interface. The parameters of stand-off distance, cutting speed, feedrate and depth of cut were dominantly affecting the surface roughness with their contributions being 9.70%, 22.70%, 20.85% and 34.47% respectively. By increasing nozzle diameter, stand-off distance and pressure, around 13.28%, 16.47% and 8.82% reduction in surface roughness is possible respectively on account of enhancement of cooling and lubrication effect; however conversely increasing the cutting speed brought around 40% increment in surface roughness.

Nanofluids, micro-lubrications and machining process optimisations − a review

Abstract: The lubrication is a prime requirement of metal cutting industries to assure high quality performance. The conventional technique of coolant flow is less economical and eco-friendly. Recently, nano fluids found better cutting fluid in machining due to potential thermal and heat transfer properties. The role of micro-lubrication techniques and process optimization are equally important for improving process performance. The literature review presents the findings of different researchers in the field of nano fluids and micro-lubrication techniques. The experimental studies were focused on better process performance using micro-lubrication techniques, especially nanofluid MQL with optimized process parameters. The thermal conductivity of water based TiO2 nano fluid shows improvement by 22% in base fluids. The case study discussed which is focused on preparation and characterization of nano fluid, experimental setup and optimization of process parameters by Jaya algorithm. Finally, application of nano fluid, and challenges during nano fluid preparation is identified. The scope of research work is recommended for further study to obtain an economical, eco-friendly manufacturing process.

Lubrication Mechanism of scCO2-MQL in the Assisted Machining of Titanium Alloys

Abstract: Cutting fluids are often used in the machining of titanium alloys to reduce processing temperature and maximize quality and productivity. The permeability of the cutting fluid in the capillary tube directly influences the effect of lubrication on cooling performance. In this study, supercritical carbon dioxide cryogenic micro-lubrication (scCO2-MQL) is used for the auxiliary machining of titanium alloys. A capillary model for scCO2-MQL-assisted cutting is proposed and established while considering the characteristics of three-phase states produced during the decompression release of scCO2. The injection temperature and characteristics of scCO2 are experimentally investigated, and the dynamic process of scCO2-MQL penetration into the capillary is analyzed. The results show that under the applied experimental conditions, the injection temperature of scCO2-MQL ranges from approximately −45 °C to 60 °C. Because scCO2 presents good solubility in oil, it has the capacity to refine the oil droplets into smaller particles, thus resulting in a higher lubricating oil content in the capillary per unit of time. This leads to enhanced lubricity that can benefit processing applications.

Evaluation of palm kernel oil as cutting lubricant in turning AISI 1039 steel using Taguchi-grey relational analysis optimization technique

Abstract: Cutting fluids have a known negative impact on productivity, human health, and the environment in the manufacturing sector. A suitable method for reducing the effect of cutting fluids on human health and the environment is minimum quantity lubrication (MQL). In this experiment, AISI 1039 steel was machined using vegetable oil lubricant and MQL. A chemical method was used to extract vegetable oil from palm kernel seeds. Then, using established techniques, the physicochemical and lubricity properties of palm kernel oil (PKO) were ascertained. The Taguchi L9 (33) orthogonal array served as the basis for the planning of the experimental design. Process parameters such as surface roughness, chip thickness ratio, cutting temperature, and material removal rate were measured during the turning operations. The multi-response outputs from TGRA were considered to simultaneously optimize the cutting parameters namely depth of cut, feed rate, and spindle speed. At a temperature of 55°C, 180 minutes, and particle sizes of 0.2–0.5 mm, an oil yield of 55% by weight was obtained. The viscosity at 40°C, specific gravity, pour, fire, cloud, and flash points of the raw PKO were 117.6 mm2/s, 0.8940 mg/ml, 21°C, 231°C, 22.3 °C and 227°C, respectively. The surface roughness and cutting temperature of PKO improved by 44% and 12%, respectively, when compared with mineral oil. The findings of this research confirmed the effectiveness of the integrated Taguchi-grey relational analysis (TGRA) optimization method and established an experimental foundation for the use of PKO minimum quantity lubrication turning.

Design of Real-Time Monitoring System for Cutting Fluids

Abstract: The paper describes the design and implementation of a cutting fluid monitoring system, as well as the design and development of an algorithm to increase the life of the cutting fluid in the machine tool reservoir. Cutting fluids are the most common type of coolant in machining. During its use, it becomes contaminated and gradually degrades until it needs to be replaced with fresh fluid. To increase its effective service life, its parameters should be monitored at regular intervals, and corrective measures such as topping up the fluid quantity and adding inhibitors and additives should be taken if necessary. For this purpose, a conceptual design of a monitoring device was developed, and a prototype device was subsequently manufactured. The device is designed as a floating probe in the storage tank. Therefore, its shape had to be designed to accommodate multiple sensors, batteries, and electronic components while remaining floating and watertight. The designed prototype was made by additive manufacturing and placed in a cutting fluid while being measured at regular intervals. In the event of non-compliant parameters, the algorithm generated corrective actions, and the machine operator could take the required steps to significantly increase the lifetime of the cutting fluid.

The Chaotic Property of BTA Deep-Hole Machining System under the Effect of Inner Cutting Fluid

Abstract: To clarify the action mechanism of parameter change on system stability, the chaotic property of BTA deep-hole machining system under the effect of inner cutting fluid was analyzed. According to the kinematic characteristics of the internal cutting fluid and the equation of the moment of momentum of the system, the kinematic equation of the boring bar considering the effect of the internal fluid was established. The critical conditions of chaos were deduced according to the Hamiltonian function and Melnikov function of the plane near-Hamilton system. The mechanism of the liquid filling ratio, cutting fluid flow velocity, and frequency ratio parameters on the system’s critical instability surface is investigated. The correlation and sensitivity of influencing factors, such as filling ratio and frequency ratio, and cutting fluid flow velocity to the sensitivity of system chaos are explored. The results show that in precision machining, the change of liquid filling ratio is positively related to the stability of the system, the change of cutting fluid flow velocity is negatively correlated with the stability of the system, and the change of frequency ratio has no monotonicity effect on the stability of the system. The sensitivity of the chaotic characteristics of the system to each parameter is bounded by the filling liquid ratio h = 0.58. When 0 ≤ h ≤ 0.58, frequency ratio ω ¯ > filling ratio h > cutting fluid flow velocity V0; when 0.58 < h ≤ 1, filling ratio h > frequency ratio ω ¯ > cutting fluid flow velocity V0. These research conclusions can lay a certain theoretical foundation for the analysis, control, and optimization of the complex mechanical behavior of BTA deep-hole machining systems in engineering practice.

A Study on the Vibration Characteristics of Al 6061 Alloy Depending on the pH Value of Cutting Fluids

Abstract: 절삭가공 중 절삭유제의 사용은 열 배출, 절삭부하 감소, 방청, 윤활 등 최적의 절삭환경 조성을 위한 필수요소이다. 그리고 절삭조건에 적합한 절삭유제의 선정과 관리는 가공품질 개선과 가공 중 유해물질 저감 등의 효과로 나타나며 나아가 생산성 향상으로 이어지는 주요한 인자이다. 일반적인 절삭가공에서 널리 사용되는 절삭유제는 수용성 절삭유제이다. 수용성 절삭유제의 상태를 파악하는 기준으로 pH 수치를 들 수 있다. pH 수치에 따른 절삭진동특성은 공작기계의 절삭성 및 가공품질을 결정하는 핵심인자이다. 본 연구에서는 아두이노를 활용한 pH 센서를 사용하여 수용성 절삭유제의 pH 수치를 측정하고 절삭유제의 pH 수치에 따른 절삭진동특성을 파악하여 절삭유제의 pH 수치가 절삭품질에 미치는 영향을 분석하고자 한다.The use of cutting fluids during machining is an essential element in creating the optimal cutting environment, including reducing heat generation, cutting load, sealing, and lubrication. Selecting and managing cutting fluids that are suitable for cutting conditions are significant factors that can lead to improvements in product quality, reduction of harmful substances during machining, and increased productivity. Water-soluble cutting fluids are widely used in general machining, and the pH value is a standard for understanding the state of water-soluble cutting fluids. The cutting vibration characteristics according to the pH value are a key factor that determines the cutting performance and product quality of machine tools. In this study, we aim to analyze the effect of cutting fluid pH value on cutting quality by using an Arduinobased pH sensor to measure the pH value of water-soluble cutting fluids and understand the cutting vibration characteristics according to the pH value of the cutting fluid.

A review on sustainable alternatives for conventional cutting fluid applications for improved machinability

Abstract: Abstract Cutting fluid is used in the field of engineering for hundreds of years, and it plays a critical role in component processing efficiency and surface quality. Water-based cutting fluid accounts for more than 90% of cutting fluid used. Conventional cutting fluids and conventional methods of coolant application are not sustainable, economical, and environmentally friendly. Cutting fluid application in large amounts also causes health issues for the operator. Researchers have developed and implemented sustainable methods like solid lubrication, cryogenic cooling, minimum quantity lubrication (MQL), and heat pipe-assisted cooling processes in the past two decades. The introduction of environmentally friendly machining techniques has considerably improved machinability in recent years. In the presented review, adverse effects of water based cutting fluids and sustainable alternative means to cut down on heat during machining and applying coolants were studied, and their pros and cons are listed. The review focuses on identifying the best available sustainable method that is economic, environmental, and is operator-friendly.