Good Surface Finish Research Articles

Microstructure and machinability evaluation in micro milling of selective laser melted Inconel 718 alloy

Selective laser melting (SLM) of Inconel 718 (IN718) alloy is common these days. The microstructure and surface integrity of fabricated components are highly depend on SLM parameters and post-processing processes. Micro milling is a promising solution to achieve good surface finish. However, the machinability of SLM fabricated IN718 is different than the wrought IN718 due to their significant differences in microstructure and properties, thus technical parameters applicable for wrought IN718 are unsuitable to SLM fabricated IN718. Therefore, the microstructure and machinability of SLM fabricated IN718 during micro milling processes were evaluated in this work, and comparisons with wrought IN718 were made. Micro milling experiments with varied spindle speed and feed rate were performed and comparisons between tool wear, surface roughness, residual stress and micro hardness were made. Further, the microstructure of SLM fabricated and wrought IN718 before and after machining were compared in terms of grain geometry and crystallographic texture. SLM fabricated IN718 shows slight grain coarsening and texture weaken behaviors, which is different with the obvious grain coarsening and slight texture strengthen phenomena of wrought IN718. The SLM fabricated component has lower compressive residual stress as compared with wrought alloy, and the tool wear, surface roughness and micro hardness values are higher while micro milling wrought IN718 alloy. The reasons leading to these differences were analyzed from the perspectives of technological characteristics and material properties. Observed phenomena and clarified mechanisms can be used as basis to determine suitable technological parameters of micro milling SLM fabricated IN718 alloy.

Numerical simulation on the permeability of non-crimp Carbon fiber epoxy using out-of-autoclave manufacturing method

Composites made using Resin Transfer Molding (RTM) processes have attractive properties to the aerospace and automotive industries because they can produce complex composite parts with good surface finishing. However, it still has a problem filling a large part with high fiber content at low injection pressure. Therefore, during the experiment, resin flow has to be the primary concern. This work presents a resin flow simulation of two types of mold where it will visualize the manufacturing process without actually doing it. Numerical simulation for the RTM manufacturing process is attempted by using Fluent-Ansys. It allows us to simulate the resin flow through the porous medium and obtain the total mold filling time and volumetric flow rate. It will lead to an explanation of the strength of the composite produced. Several assumptions and techniques are used to simplify the problem. Some variables, such as porosity and pressure injection, will be varied to see the effect of those variables on the RTM manufacturing process. According to the simulation result, porosity and pressure injection affect the RTM manufacturing process, especially for resin filling time and volumetric flow rate. The increase of porosity will increase the flow time, while pressure injection will decrease the flow. It happens due to how easy the resin flows through the porous medium, and the total area needs to be filled by the resin. This work is validated by comparing the obtained results with analytic solutions for a specific mold of Darcy’s law.

Characterization of electric discharge machining of titanium alloy utilizing MEIOT technique for orthopedic implants

In this research work, medical grade titanium alloy Ti4Al6V was electric discharge machined with an objective of attaining mirror finish for orthopedic implants. Experiments were conducted by varying tool materials, discharge current, pulse on time and pulse off time whereas the responses chronicled are material removal rate, electrode wear rate and surface roughness. The aluminium (A), copper (C) and aluminium alloy reinforced with graphite particles of various weight percentage (5-A1,10-A2,15-A3) were used as tool materials. The composites were fabricated using stir casting technique. The findings showed that the titanium alloy machined with A1 composite tool offers the highest MRR, the C tool has the lowest EWR, and the A2 composite tool results in good surface finish. The surface of specimens produced using A1 tool exhibits poor surface quality owing to the eczema surface. Specimens machined with the C tool have a remelted layer, pockmarks, and an uneven fusion structure, which were not present in specimens machined with the A2 tool. MOORA-ELECTRE Integrated Optimization Technique (MEIOT) was applied to select the best parametric combination and the best electrode material.

Effect of Process Parameters on the Quality of Laser-Cut Stainless Steel Thin Plates

At present, laser cutting is currently employed to cut metallic plates, due to their good finish and dimensional quality, as well as because of the flexibility of the process to obtain different shapes. In the present paper, surface roughness, dimensional accuracy, and burr thickness of thin plates of 0.8 mm are studied as functions of different process parameters: pulse frequency, pulse width, and speed. Eight different experiments were performed according to a full 23 factorial design, with two replicates each. Square specimens of 10 mm × 10 mm were cut. Arithmetical mean roughness Ra was measured with a contact roughness meter, and the dimensions and burr thickness with a micrometer. Ra values ranged between 1.89 and 3.86 µm, dimensional error values between 0.22 and 0.93%, and burr thickness between 2 and 34 µm. Regression analysis was performed, and linear models were obtained for each response. Results showed that roughness depends mainly on frequency, on the interaction of frequency and pulse width and on pulse width. Dimensional error depends on pulse width, frequency, and the interaction between pulse width and speed. Burr thickness is influenced by frequency, pulse width, and the interaction between frequency and speed. Multi-objective optimization showed that, in order to simultaneously minimize the three responses, it is recommended to use high frequency (80 Hz), high pulse width (0.6 ms), and high speed (140 mm/min). The present study will help to select appropriate laser cutting conditions in thin plates, in order to favor good surface finish and dimensional accuracy, as well as low burr thickness.

Development of a vibration free machine structure for high-speed micro-milling center

The demand of ultra-precision micro-machine tools is growing day by day due to exigent requirements of miniaturized components. High accuracy, good dimensional precision and smooth surface finish are the major characteristics of these ultra-precision machine tools. High-speed machining has been adopted to increase the productivity using high-speed spindles. However, machine tool vibration is a major issue in high-speed machining. Vibration significantly deteriorates the quality of micro-machining in terms of dimensional precision and surface finish. This article describes a design methodology of a closed type machine structure for vibration minimization of a high-speed micro-milling center. The rigid machine structure has provided high stiffness and the damping capability to the machine tool without utilizing vibration absorbers. The models of the machine structures have been generated and assembled in AutoCAD 3D. The performance of the integrated micro-milling machine tools was determined by finite element analysis. The best model has been selected and proposed for manufacturing. Additionally, simulation results were validated by comparing with experimental results. Eventually, after manufacturing and assembly, experiments have been performed and it was observed that the amplitude of vibration was approaching towards nanometer level throughout the working range of the high-speed spindle. The machine tool was capable to fabricate miniaturized components with smooth surface finish.

WITHDRAWN: Modeling and analysis of CNC milling process parameters on surface integrity of aluminum hybrid composite

Abstract The machining of Aluminum cross breed composite on higher speed CNC processing machine have accepted significance as a result of its extensive application in aviation enterprises, maritime ventures and car businesses and so on. Many scholars carried out investigation and researches in this area but very few studies have been observed in the aluminum hybrid composite. In this study, modeling of surface characteristics of milling process was carried out. Process parameters such that Feed rate, depth of cut and cutting speed are the input parameters reserved into distress in this research work. According to Taguchi L9 orthogonal array, nine experiments are planned. Surface roughness has been measured using Mitatuyo surf reader. Linear regression models have been developed and the results are validated by conducting selected additional set of experiments. The study reveals that Taguchi orthogonal array can generate truthful and applicable outputs deemed as optimal in the case of milling the composite. Spindle speed is the most significant parameter than feed rate and depth of cut for good surface finish. Depth of cut was the least significant factor over spindle speed and feed rate. The least predicted surface roughness (Ra = 1.43 µm) was attained at 75 mm/min feed rate at 4000 RPM spindle speed with depth of cut of at 0.25 mm. It was successfully validated with confirmation experiment.

Effect of different topologies on microstructure and mechanical properties of multilayer coatings deposited by laser cladding with Inconel 625 wire

Different topologies of clad coatings mean different cladding strategies and cyclic thermal histories. In this study, two types of Inconel 625 multilayer coatings with parallel topology (The cladding direction between adjacent layers was parallel.) and perpendicular topology (The cladding direction between adjacent layers was perpendicular.) were fabricated respectively on 316 L substrate using an off-axis wire cladding system. The effects of different topologies on microstructure and mechanical properties of the coatings were investigated. The finite element (FE) model was adopted to predict the cyclic thermal histories in different topologies. The results showed that morphologies of the two topologies both presented good surface finish and free of crack and pore defects. Compared with perpendicular topology, for coatings with parallel topology, columnar dendrites in the upper and lower layers exhibited relatively consistent orientation since they complied with the movement direction of heat source. The parallel topology also exhibited better mechanical properties along the cladding direction due to the uniform cyclic thermal history. Although Laves phase pinned the migration of grain boundaries, it was also the main cause of producing microvoids that led to the fracture.

Sustainable Machining of Hastelloy in EDM Using Nanoparticle-Infused Biodegradable Dielectric Fluid

Electrical discharge machining (EDM) is the unconventional machining technique used extensively for machining difficult-to-machine materials with lower material removal rate and poor surface roughness. To overcome these drawbacks, synthetic dielectric fluid is replaced with nanoparticle-infused biodegradable dielectric fluid in the machining of Hastelloy material. This paper focusses on the machining performances of Hastelloy in EDM using various concentrations of 0.5, 1 and 1.5 wt% of nano-zirconia dispersed in biodegradable canola oil methyl ester as the dielectric medium, and these characteristics were compared with those of the synthetic dielectric medium. Based on the D-optimal design coupled with cuckoo search algorithm, machining was carried out with various dielectric fluids and their influences on the metal removal rate, surface roughness, surface morphology and surface topography in EDM studied. The results proved that the canola oil methyl ester containing 0.5 wt% of nano-zirconia (C-0.5) had provided good surface finish, better surface topography, smooth surface morphology and high metal removal rate in comparison with the other dielectric fluids used in this study.

Observations of Machining Performance during Turning AA6351-B4C Composite

Abstract This study investigates the machining characteristics of stir-cast AA6351-boron carbide composite under dry condition. The influences of input parameters on output responses, such as temperature rise, cutting force, tool wear, and surface roughness, are investigated. The monolayer titanium nitride–coated solid carbide insert tool CNMG120412 (80° diamond shaped with a nose radius of 1.2 mm) has been used to perform the experiments. The temperature and cutting forces are measured by using a FLIR infrared thermal image camera and piezoelectric dynamometer. The reduction in temperature is noted at a low spindle speed (Vc), which is due to the discontinuous chip formation. The increase in feed rate (f) has reduced the coefficient of friction (μ) as a result of a decrease in the friction angle. The lowest value of μ, 0.5567, is obtained at a low Vc and a high f. The increase in temperature at a high Vc reduces the specific cutting pressure and results in a low thrust force. The tool wear is examined by using a scanning electron microscope to analyze the wear mechanisms. At a high Vc, an increase in temperature reduces mechanical load and protects the tool from abrasion wear; it results in good surface finish. A low surface roughness value of 1.08 μm is achieved at a high Vc and ensures the surface quality.

Multiphysics simulation and experimental investigation of microtool fabricated by EMM

ABSTRACT Due to the continuous demand for miniature products, demand for microtool increases. Various conventional and non-conventional methods have been employed for the fabrication of microtool. In this paper, electrochemical micromachining (EMM) is used for the fabrication of microtool as it offers good accuracy, no heat generation, contactless process, no tool wear and good surface finish. The microtool of different shape and sizes are fabricated from Tungsten tool having initial diameter of 500 µm using the two different techniques. In the first technique, the tool is placed inside the pre-made hole in stainless steel (SS) plate and the effect of tool rotation is analyzed. In the second technique, the tool is kept adjacent to SS plate and the analysis is based on the interelectrode gap (IEG) during machining. COMSOL® Multiphysics software is used to create a 2D model to study the variation of current density distribution in the interelectrode gap. First technique with tool rotation results in conical microtool with good surface finish and second technique results in cylindrical microtool with diameter less than 100 µm. Simulation results are validated with the experimental results with an error below 15%.

Performance Assessment of Polymeric Composite Wrap to Repair Damaged Pipelines Exposed under Accelerated Environment Conditions

Fiber-reinforced polymer composites are used as emerging materials to repair oil and gas transmission pipelines without stopping the flow of fluids inside. These pipelines are subjected to harsh environment conditions such as being buried under soil and being exposed to high humidity, high temperatures, and different chemicals. It is important to predict the useful life of composite repairs in these harsh conditions in order to design better and to have robust repair solutions. This study evaluates mechanical properties, namely tensile strength tensile modulus, flexural strength, flexural modulus, and lap shear strength, of composite laminates when exposed to harsh environmental conditions such as hot-wet [70°C/85% relative humidity (RH)] for 0, 2, 4, and 6 weeks, steam autoclave [121°C and 1,05,000 Pa (1.05 bar)] for 0, 6, and 12 h, and ultraviolet (UV) ray exposure of type UVA-340 at 50°C for 0 and 2 weeks. The glass fiber–reinforced polymer (GFRP) composite laminates are prepared by hand layup process and are cut using a water-jet cutting process to avoid machining defects and to keep a good surface finish. The specimens are exposed to these corresponding environmental conditions for different periods of time, and the changes in their mechanical properties are studied. The tensile strength, flexural modulus, and lap shear strength values are compared with unexposed specimens. Decreases in strength and modulus values are observed for exposed specimens. A simple empirical expression is developed to predict the usable lifetime of a composite repair system exposed to such different harsh environmental conditions.

Comparative analysis of chatter in micro end milling operations

The advancement in microfabrication in pursuit of miniaturization is cutting a dynamic role for micro-milling. Micro-milling is a fast and cost-efficient threedimensional fabrication method with the ability to achieve good accuracy, low surface roughness and extraordinary material removal rate (MRR) compared to some other micro manufacturing processes. Given the need for components with high dimensional integrity, identification of appropriate machining conditions is very vital to getting good surface finish. It is also required to couple different complex dynamics which are associated with this machining technique. Chatter during milling and micro-milling process bring adverse effects in surface quality, dimensional accuracy and in tool life. There is need for versatile modelling of micro end-milling dynamics in order to understand how chatter affects the micro end milling operation and to advance the synthetic application of several chatter stability parameters to overcome the limitation imposed by the single chatter stability criterion. This study performs a linear and non-linear analysis of chatter in micro end milling based on the major influential parameters. In addition, a detailed time domain simulation for micro end milling was performed to predict the force a displacement resulting from variable cutter geometries. This dynamic simulation results have significant impact on the actual micro milling process towards the manufacturing of miniaturized parts.

Multi-response optimization of machining factors in pocket milling of AISI304 using grey relational analysis

Pocket milling finds applications in ship building and aerospace industries. To cut the required profile of the pocket on the material various tool trajectories may be used. Surface roughness is one of the quality parameters to accept products at the same time production time must be reduced to reduce the production cost. This shows the need of selecting the best parameters machining parameters to get good surface finish with less production time. Tool trajectories also play a vital role in pocket generation and production time. In the current study, first, optimum machining parameters are identified for AISI304 using Taguchi L9 Orthogonal Array and Grey Relational Analysis. Experiments are done with Speed (S), Feed (F) and Stepover (SO) as the influencing parameters. Secondly, suitable tool path is to be identified to improve the surface quality (SR) and Material Removal Rate (MRR). Two tool paths viz, follow periphery and zigzag are used to generate pockets. For each tool trajectory, from the obtained results, Grey Relational Grade is calculated. The combination of parameters with highest Grey Relational Grade is identified as the optimal parameters. Confirmation experiments indicate that predicted responses are closer to the optimal values.

Application of Digital Logic Method in the Selection of Suitable Polymeric Materials for Ceiling Tiles Production

Polymeric materials are widely employed in the production of ceiling tiles due to their attractive qualities such as thermal insulation, low water absorption characteristics, light weight, availability, cost effectiveness and their good surface finishing. This study focused on the production, property characterization and the optimization of five different polymer composite material which are 20SE (20 wt.% of sisal reinforced epoxy), 20JH (20 wt.% jute fiber reinforced high density polyethylene), 20BP (20 wt.% bagasse fiber reinforced polypropylene), 6CP (20 wt.% coconut shell ash reinforced Polyvinyl chloride) and 20CL (20 wt.% cotton reinforced low density polyethylene). Selected properties considered are flexural and tensile strengths, thermal conductivity, water absorption and bulk density. The values obtained after characterization were evaluated using digital logic method so as to determine the composite material with the optimum property while putting their cost effectiveness into consideration. The result showed that 20BP (20 wt.% bagasse fiber reinforced polypropylene composite) had the highest performance index and figure of merit, making it the most preferred polymeric composite for ceiling tiles application.

Rheological characterization of newly developed fly-ash mixed polymeric media and its finishing performance through abrasive flow machining

One of the essential requirements for efficient performance and longer service life of machined components is a good surface finish. Though there are other traditional finishing processes like lapping, grinding, and honing. However, the major disadvantage associated with them is, they can process only simple geometry. Abrasive flow machining (AFM), due to its self-deforming characteristic, is used for finishing parts having predominantly irregular geometry. All AFM processes comprise a machine, fixture, and media (i.e., carrier/or putty mixed with abrasive particles) among which, media (viscoelastic polymer) plays a dominant role. The commercial abrasive, which is one of the constituents of the viscoelastic media for AFM, which provides the finishing action (abrasion), are very expensive and hence it is a major problem for the small industries. Also, the finishing cost per unit component (workpiece) with a commercial media having SiC/diamond abrasives turns out to be very high, which makes its use uneconomical for mass finishing. Therefore, in the present research work, an attempt has been made to develop an alternative low-cost AFM media by replacing commercial abrasives with waste coal fly-ash. The developed media are characterized through static and dynamic rheological tests, thermogravimetric analysis, and finishing experiments on aluminum and mild steel workpieces to judge the performance of newly developed media concerning the traditional one. The percentage improvement obtained in average surface roughness(ΔR a ) through fully fly-ash-based media (68% fly-ash) is ~56% for the aluminum and ~49% for mild steel workpieces.

Experimental Investigation on Surface and Machining Characteristics of Micro ED Milling of Ti-6Al-4 V with Different Nano Powder Mixed Dielectrics

Micro ED milling is a micro machining technique for machining of high-quality micro parts on the electrically conductive material. Achieving a good surface finish with higher material removal is difficult in Micro ED (μED) Milling due to the short circuits and arcing attributed to partial removal of debris. In this research work, an attempt has been made to improve the quality of machined surfaces in the milling process without compromising the machining characteristics using nano powder mixed dielectrics such as Silicon carbide (SiC) and Carbon nano tubes (CNT). The milling trails were carried out using Tungsten carbide (WC) electrodes under adopted levels of powder concentration and discharge energy region in order to determine the best condition for achieving maximum material removal and excellent surface finish. Further, the morphology of the machined surface was examined using Scanning Electron Microscope (SEM) and found that ridges, crater size and overlapping of craters were considerably reduced due to addition of nano powders in dielectric resulted in high surface finish. The micro cracks are larger with higher discharge energy for all dielectrics used, whereas it is significantly reduced with nano powder mixed dielectrics as compared to plain dielectric. CNT powder offered high MRR and the minimum EWR as compared to other dielectrics used. Both the CNT and SiC powder mixed dielectrics have marginally improved the surface hardness. Results indicated that the electrical conductivity of dielectric has a significant effect on machining and surface characteristics. The surface texture achieved with CNT mixed dielectric looks better than that of other dielectrics: especially with the higher order of powder concentration of 0.9 g/l. Milling trails were designed using full factorial design for plain and nano powder mixed dielectrics.

Defect-free high-feed milling of Ti-6Al-4V alloy via a combination of cutting and wiper inserts

Ti-6Al-4V alloy machining is challenging due to inherent properties. Wiper inserts improve the surface finish at higher feed rates because of multi-radii geometry. Wiper inserts when combined with the cutting inserts can provide smooth surface finish. The current work is aimed to study the influence of cutting and wiper inserts in Ti-6Al-4V alloy milling while considering wear scar of tool/life, surface roughness, surface topography, micro-hardness, and microstructural evaluations as output responses under higher levels of feed rates in dry machining. The combination of cutting insert along with wiper geometry provides machining innovation due to the fact that good surface finish can be achieved in a single step. Three levels of feed rate (f) (1.2, 1.4, 1.6 mm/revolution) along with three levels of depth of cut (ap) (0.25, 0.40, 0.50 mm) were employed for the experimentation. The variation in workpiece surface roughness (Ra) was found in between 0.3 and 0.71 μm-Ra. Surface topography analysis under the scanning electron microscope (SEM) of the machined specimen revealed no voids/cracks; however, scratch marks/welding of microchips were noticed. No alteration in microstructure was found when milling at 1.2 and 1.4 mm/revolution feed rate. A white layer deepened to 18 μm from the milled surface was seen at a feed rate of 1.6 mm/revolution. In addition, approximately 15% increase in micro-hardness was observed beneath the milled surface when evaluated machining variables were at their peak levels, i.e., at 1.6 mm/revolution and 0.5 mm respectively, while only 5.4% increase in the said response was observed at f of 1.2 mm/revolution.

Effects of SiO2-Al2O3-ZrO2 Tri-hybrid Nanofluids on Surface Roughness and Cutting Temperature in End Milling Process of Aluminum Alloy 6061-T6 Using Uncoated and Coated Cutting Inserts with Minimal Quantity Lubricant Method

In machining, heat concentration is generated at the surface contact between the tool and workpiece. This is the effect of hard frictions at the shear cutting plane to remove hard and brittle materials. The highly adhesive behavior of aluminum alloy 6061-T6 is more severe in higher cutting temperature, which may affect tool failures such as flank wear, tool chip and built-up edge, particularly on the edge of cutting inserts during the process. As a result, this may lead to the rough surface and low-dimensional accuracy of the machined parts. Realizing that metal-cutting industry players are demanding high-quality products with better surface finish and dimensional accuracy led to this study. Aluminum alloy 6061-T6 is a standard alloy used in automotive, aerospace and food packaging due to good hardness, high strength-to-weight ratio, resistance to corrosion and weldability. In order to address this problem, a newly developed metal working fluid which is SiO2-Al2O3-ZrO2 tri-hybrid nanofluid is applied in the cutting zone to achieve a good surface finish of the machined parts and lowering the cutting temperature. This study is the first attempt to enhance machining performance, particularly at high-speed machining, by employing a combination of tri-hybrid nanofluids and a minimum quantity lubricant technique. Industrial standards include uncoated tungsten carbide and CVD TiCN-Al2O3 carbide used during machining of aluminum alloy 6061-T6. The minimum quantity lubricant method is an alternative in supplying the lubricant into the machining zone due to flood machining and conventional fluid possess safety, health, economic and environmental effects. In this study, the experimental data were analyzed statistically using analysis of variance and response surface methodology. The responses studied were reduced significantly when tri-hybrid nanoparticles present at the cutting interface with higher MQL flow rate and concentration. There are two-factor interactions which are significant to the responses studied. Therefore, the combinations of MQL and excellent tri-hybrid nanofluids characteristics have enhanced between 16 and 76% of surface roughness and the cutting temperature, respectively, which is very promising in the future.

Machining, Characterization and Optimization: A Novel Approach for Machining Channels on Silicon Wafer Using Tailor-Made Micro Abrasive Jet Machining

Literature reveals that machining a silicon wafer is very arduous due to its high brittle nature and low fracture toughness. Researchers have attempted to machine features on a silicon wafer using both conventional and non-conventional processes and both have their merits & demerits. Abrasive jet machining (AJM) is one of the efficient non-conventional machining methods for machining hard and brittle materials. Removal of material occurs by impact erosion and is free from Heat Affected Zone (HAZ) and resolidification. These advantages make AJM a potential process for machining silicon wafers. Therefore an attempt has been made to machine channels on silicon wafers using a Tailor-made AJM setup. The process parameters selected for machining channels on a silicon wafer are air pressure, Feed rate (FR), and Standoff distance (SOD). The output responses considered for characterization are material removal rate (MRR), channel characteristics like width, depth, and Surface Roughness (Ra). The machined Channels are found to have sufficient depth and good surface finish and are free from heat affected zone and resolidification. X-Ray Diffraction (XRD) analysis has indicated the presence of embedded SiC particles in the channel. GRA method is utilized to achieve an optimal condition of higher depth and MRR, smaller width, and Ra. Also, the significance and percentage contribution of process parameters are found out through ANOVA and obtained results are presented in the paper.

Advances in precision manufacturing towards eco-friendly grinding process by applying MQL with cold air compared with cooled wheel cleaning jet

With the evolution of the sustainable industry, the grinding process seeks to follow the requirements to continue to be highly employed when precision and low-dimensional tolerances are required in the workpieces. In this way, the cutting fluids used in the process, which are essential for a good surface finish, are the main impasse to ensure that the process becomes eco-friendly. Therefore, a widespread lubri-refrigeration method in the industry is the flood technique, which uses a lot of fluid to reduce the high temperatures generated during grinding. However, the use of the flood method generates many undesirable residues that affect the machine operator, the environment, and production costs. Thus, several alternatives have emerged to address these problems, for example, the minimum quantity of lubricant (MQL), the wheel cleaning jet system (WCJ), and the application of cooled air (CA). Therefore, this work sought to analyze the combination of these systems (MQL+CA, MQL+WCJ, and MQL) in the grinding of AISI 4340 steel using an aluminum oxide wheel (Al2O3) and to verify their performance compared with the flood method, in addition to employing a new method known as cooled wheel cleaning jet (CWCJ). Therefore, the tests of surface roughness (Ra and Rz), roundness error, diametrical wheel wear, G ratio, grinding power, tangential cutting force, and microhardness were performed, and optical, confocal, and scanning electron microscopy also were analyzed. Thus, the results that came closest to the flood method in all tests were achieved by systems that applied grinding wheel cleaning (MQL + WCJ and MQL + CWCJ), being that in the diametrical wheel wear and G ratio the MQL + CWCJ even managed to surpass it. Besides, the MQL+CA union showed better values when compared with MQL without any assistance. Thus, applying MQL with helper systems, mainly CWCJ, contributed to a more economical, efficient, and sustainable grinding process.