Qualitative Evaluation of Machined Surface of Aluminum Alloy AlCu4Mg1 Depend on Feed Rate

The wear-resistance performance of machined surface is an important factor in the evaluation of surface quality and precision in aerospace manufacturing industry. By using high-speed Ring-Block friction and wear machine (MRH-3), the influence of cutting parameters in milling aluminum alloy 7050-T7451 on wear-resistance of machined surface including friction coefficient and wear quantity are experimentally investigated. The wear-resistance is particularly sensitive to cutting speed and feed rate. The friction coefficient has marked drop trends as cutting speed increases. The influence of cutting speed on wear quantity is more complicated and the tendency of wear quantity was ascend in first and descend at last (v>900/min). The results show that the influence of cutting parameters on wear-resistance was also positively correlated with surface roughness and work-hardening of machined surface. The high work-hardening and surface quality had the promoting effecting on wear-resistance. The experiment and analysis results show that the machined surface by high speed cutting and lower feed rate has more superior in surface quality and wear-resistance performance comparing with conventional cutting speed.

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Effect of Machining Parameters in Milling Aluminum Alloy 7075-T6 under MQL Condition

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.a2231.129219 ◽

2019 ◽

Vol 9 (2) ◽

pp. 109-113

Keyword(s):

Surface Roughness ◽

Aluminum Alloy ◽

Tool Life ◽

Feed Rate ◽

Cutting Tool ◽

Cutting Speed ◽

Machining Parameters ◽

Machined Surface ◽

Machined Surface Roughness ◽

Aluminum Alloy 7075

Minimum quantity lubrication (MQL) is an eco-friendly method, where a small amount of fluid was sprayed to cutting edge in mist form with the aid of the air. The foregoing studies revealed that inappropriate machining parameters without the assistance of the cutting fluid methods became a major challenge in milling aluminum alloy 7075-T6. The paper presents the findings of the experimental work to assess the effect of machining parameters towards cutting tool life and machined surface roughness in milling aluminum alloy 7075-T6 at high cutting speed under MQL condition. An eight-run experiment was designed according to full factorial design based upon two levels of cutting speed (500 m/min, 600 m/min), feed rate (0.12 mm/tooth, 0.15 mm/tooth), and axial depth of cut (1.40 mm, 1.70 mm) and then analyzed employed ANOVA to determine the significant machining parameters. The cutting tool life and machined surface roughness were assigned by the rejection criterion of tool flank wear in the milling operation. The optical microscope and portable surface roughness tester were applied to analyze tool wear and average surface roughness value. Cutting speed and feed rate were significantly contributing to the tool life and surface roughness. The longest tool lifespan of 20.14 minutes and lowest surface roughness value of 0.569 µm were obtained at a speed of 500 and 600 m/min, respectively, with a low combination of the rest of parameter which are 0.12 mm/tooth and 1.40 mm.

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Experimental Research on Surface Roughness of Ultrasonic Assisted Grinding on 7075 Aluminum Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1047.62 ◽

2021 ◽

Vol 1047 ◽

pp. 62-67

Author(s):

Shen Wang ◽

Le Tong ◽

Guang Jun Chen ◽

Mao Xun Wang ◽

Bin Dai ◽

...

Keyword(s):

Surface Roughness ◽

Aluminum Alloy ◽

Processing Parameters ◽

7075 Aluminum Alloy ◽

Machined Surface ◽

Ultrasonic Assisted Grinding ◽

Great Performance ◽

Ultrasonic Assisted ◽

Conventional Grinding ◽

Micro Morphology

7075 aluminum alloy is widely used due to its great performance, especially in aerospace area. In this paper, ultrasonic-assisted grinding technology is used to process 7075 aluminum alloy. The data is obtained through experiments, and the surface roughness and morphology of ultrasonic assisted grinding and conventional grinding under different spindle speeds, feed rates, and amplitudes are analyzed. Research has found that the increase in spindle speed and amplitude will improve the quality of the machined surface and reduce the surface roughness by 82.1% and 36%. However, with the increase of feed rate, the surface quality decreased significantly, and the surface roughness increased by 55.6%. The surface micro-morphology of the machined workpiece is observed, and the effects of different processing parameters on the surface micro-morphology are obtained.

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Study on Improving Accuracy in Robotic Milling of Aluminum Alloy

Volume 3: Manufacturing Equipment and Systems ◽

10.1115/msec2018-6476 ◽

2018 ◽

Author(s):

Shaochun Sui ◽

Kai Guo ◽

Jie Sun ◽

Yiran Zang

Keyword(s):

Aluminum Alloy ◽

Industrial Robot ◽

Vibration Signal ◽

Industrial Robots ◽

Machining Process ◽

Cnc Machine ◽

Machined Surface ◽

Improving Accuracy ◽

High Level ◽

Monolithic Components

Nowadays, the application of using industrial robots in manufacture is a diminutive due to its own low rigidity and low stiffness. This leads to high level of vibrations that limits the quality and the precision of the workpiece. So they are usually used for welding, grinding and paint shop. However, the potential of industrial robot applications in machining has be realized. The volume of monolithic components is large and there are many issues in machining process such as geometric tolerance and quality of machined surface. In such cases the traditional CNC machine is replaced by industrial robots, which will reduce the production cost, reduce labor and increase the efficiency. In this paper, the milling experiment of 7050-T7451 aeronautical aluminum alloy was carried out by using industrial robot KR210 R2700. In addition, the experiment was employed to study the influence of milling speed, feed-rate, cutting depth and cutting width on vibrations, surface roughness was also measured to evaluate the machining quality. Besides, the axis of angle was changed which led to the different industrial robot’s postures. The vibration signal of different postures was acquired, which was used to analysis the optimal workspace of industrial robot. The best process parameters were obtained, which will play a guiding significance on the actual production.

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An Investigation To Achieve a Good Surface Integrity in WEDM of Ti-6242 Super Alloy

10.21203/rs.3.rs-925898/v1 ◽

2021 ◽

Author(s):

Sonia Ezeddini ◽

Wajdi Rajhi ◽

Mohamed Boujelbene ◽

Emin Bayraktar ◽

Sahbi Ben Salem

Keyword(s):

Surface Roughness ◽

Pulse Duration ◽

Surface Integrity ◽

Surface Finish ◽

Feed Rate ◽

Cutting Parameters ◽

Machined Surface ◽

Good Surface ◽

Pulse On Time ◽

Super Alloy

Abstract Ti-6242 is a super alloy which exhibits the best creep resistance among available titanium alloys and is widely used in the manufacture by WEDM of aircraft engine turbomachinery components. However, the final quality of wire EDMed surface is a great challenge as it is affected by various factors that need optimization for surface integrity and machine efficiency improvement. The aim of this study is to investigate the effect of a set of cutting process parameters such as pulse on time (Ton), servo voltage (U), feed rate (S) and flushing pressure (p) on surface roughness (SR) when machining Ti-6242 super alloy by WEDM process using a brass tool electrode and deionized water as a dielectric fluid. WEDM experiments were conducted, and SR (Ra) measurement was carried out using a 3D optical surface roughness-meter (3D–SurfaScan). As a tool to optimize cutting parameters for SR improvement, Taguchi's signal‐to‐noise ratio (S/N) approach was applied using L9 (3^4) orthogonal array and Lower-The-Better (LTB) criteria. Substantially, the findings from current investigation suggest the application of the values 0.9 µs, 100V, 29 mm/min, and 60 bar for Ton, U, S and p cutting parameters, respectively, for producing a good surface finish quality. Percent contributions of the machining parameters on SR (Ra) assessed based on ANOVA analysis are 62.94%, 20.84%, 11.46% and 4.74% for U, S, Ton and p, respectively. Subsequently, accurate predictive model for SR (Ra) is established based on response surface analysis (RSA). The contour plots for SR (Ra) indicate that when flushing pressure p converges to a critical value (80 bar), a poor-quality surface finish is highly expected with the excessive increase in U and S. Electron microscope scanning (SEM) observations have been performed on machined surface for a wide range of cutting parameters to characterize wire EDMed surface of Ti-6242. SEM micrographs indicate that the machined surface acquires a foamy structure and shows white layer and machining-induced damage that the characteristics are highly dependent on cutting parameters. At high servo-voltage, the decrease in pulse on time Ton and feed rate S results in a large decrease in overall machining-induced surface damage. Moreover, for high servo-voltage and feed rate levels, it has been observed that pulse on time could play a role of controlling the surface microcracks density. In fact, the use of a low pulse duration of cut combined with high servo-voltage and feed rate has been shown to inhibit surface microcracks formation giving the material surface a better resistance to cracking than at high pulse duration.

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Effect of Milling Speed and Feed on Surface Residual Stress of 7050-T7451 Aluminum Alloy

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.499.217 ◽

2012 ◽

Vol 499 ◽

pp. 217-222 ◽

Cited By ~ 1

Author(s):

C. Li ◽

Yi Wan ◽

R.R. Zhang ◽

Zhan Qiang Liu

Keyword(s):

Residual Stress ◽

Aluminum Alloy ◽

Cutting Speed ◽

Diffraction Method ◽

Cutting Condition ◽

Feed Speed ◽

X Ray Diffraction ◽

Surface Residual Stress ◽

Orthogonal Direction ◽

Machined Surface

The residual stress in the milling of 7050-T7451 aluminum alloy was measured using X-ray diffraction method in which Psi-oscillation, Phi-oscillation and peak fit were adopted. Cutting speed and feed are main variables which were considered in this study. The results show that compressive residual stresses are generated in surface for the down milling generally, which is mainly due to burnishing effect between the tools flank face and the machined surface. In feed and its orthogonal direction, the effect of cutting speed and feed speed on residual stress is similar. Therefore, required residual stress can be achieved by controlling the cutting condition such as cutting speed, feed speed etc.

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Tool Posture Planning Method for Low Rigidity Workpiece Considering Elastic Deformation Caused by Cutting Force

JSME 2020 Conference on Leading Edge Manufacturing/Materials and Processing ◽

10.1115/lemp2020-8567 ◽

2020 ◽

Author(s):

Jun'ichi Kaneko ◽

Yuki Okuma ◽

Shumpei Sugita ◽

Takeyuki Abe

Keyword(s):

Cutting Force ◽

Elastic Deformation ◽

Feed Rate ◽

Machining Process ◽

Machining Time ◽

Machined Surface ◽

Nc Program ◽

Blade Shape ◽

Tool Posture ◽

The Moment

Abstract In machining process for a workpiece with low rigidity such as a blade shape, it is required to consider elastic deformation of the workpiece shape itself due to cutting force. Conventionally, reduction of the cutting force in machining process is achieved by optimization of feed rate value in NC program. On the other hand, since a decrease in the feed rate causes an increase in machining time. So, other optimization algorithm is required. In this paper, a new method to suppress the elastic deformation of the workpiece by changing tool posture in multi-axis controlled machining is proposed. The proposed method is intended for finish machining process for blade shape with a ball end mill. In the proposed method, first, the cutting force loaded on the workpiece surface in a certain posture candidate is predicted, and an instantaneous cutting force at the moment when the machining surface is generated is estimated by model-based computer simulation. Based on this results, the amount of elastic deformation on the machined surface is estimated by FEM. This process is repeated at each cutter location and tool posture candidate, and the new tool posture that can minimize machining error caused by the elastic deformation is determined at each cutter location.

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Surface Smoothing of A5083 Aluminum Alloy Plate by Friction Stir Forming

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.803.50 ◽

2019 ◽

Vol 803 ◽

pp. 50-54

Author(s):

Takahiro Ohashi ◽

Kento Okuda ◽

Hamed Mofidi Tabatabaei ◽

Tadashi Nishihara

Keyword(s):

Aluminum Alloy ◽

Feed Rate ◽

Metal Plate ◽

Spindle Speed ◽

Back Surface ◽

Alloy Plate ◽

Friction Stir ◽

Shoulder Diameter ◽

Aluminum Alloy Plate ◽

Aluminum Plates

This paper provides a framework for the transcription of the surface of a mirror-finished die onto a metal plate by friction stir forming (FSF). In FSF, a material is put on a die, then friction stirring was conducted on its back surface for the transcription of the profile of the die onto the material. In this paper, a mirror-polished die of JIS SUS304 stainless steel with surface roughness Sz 0.014 mm and a probe-less friction-stirring tool in 18 mm shoulder diameter were employed for the experiment. A5083P-O aluminum plates, 3 mm thick, were utilized as base metals for the transcription. The authors varied tool spindle speed and tool feed rate to evaluate the forming results. Consequently, a mirror-finished surface under the friction-stirring tool was successfully transferred from the die to the aluminum alloy plate. The roughness of the base metal before processing was Sz 0.022 mm and that of the processed metal was Sz 0.012–0.016 mm. Higher spindle speed and faster feed rate resulted in a smoother surface; it is thought that high spindle speed and faster feed rate should be effective for higher contact pressure between a die and a material.

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Characterization of Cutting-Induced Heat Generation in Ultra-Precision Milling of Aluminium Alloy 6061

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.552.201 ◽

2013 ◽

Vol 552 ◽

pp. 201-206

Author(s):

Su Juan Wang ◽

Suet To ◽

Xin Du Chen

Keyword(s):

Surface Roughness ◽

Surface Quality ◽

Heat Generation ◽

Feed Rate ◽

Dimensional Accuracy ◽

Precision Machining ◽

Machined Surface ◽

Single Crystal Diamond ◽

Ultra Precision ◽

Alloy 6061

The technology of ultra-precision machining with single crystal diamond tool produces advanced components with higher dimensional accuracy and better surface quality. The cutting-induced heat results in high temperature and stress at the chip-tool and tool-workpiece interfaces therefore affects the materials and the cutting tool as well as the surface quality. In the ultra-precision machining of al6061, the cutting-induced heat generates precipitates on the machined surface and those precipitates induce imperfections on the machined surface. This paper uses the time-temperature-precipitation characteristics of aluminum alloy 6061 (al6061) to investigate the effect of feed rate on the cutting-induced heat generation in ultra-precision multi-axis milling process. The effect of feed rate and feed direction on the generation of precipitates and surface roughness in ultra-precision raster milling (UPRM) is studied. Experimental results show that heat generation in horizontal cutting is less than that in vertical cutting and a larger feed rate generates more heat on the machined workpiece. A smaller feed rate produces a better surface finish and under a larger feed rate, scratch marks are produced by the generated precipitates and increase surface roughness.

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Machinability Research on the Micro-Milling for Graphene Nano-Flakes Reinforced Aluminum Alloy

Metals ◽

10.3390/met9101102 ◽

2019 ◽

Vol 9 (10) ◽

pp. 1102 ◽

Cited By ~ 2

Author(s):

Na ◽

Xu ◽

Han ◽

Liu ◽

Keyword(s):

Surface Roughness ◽

Aluminum Alloy ◽

Chip Morphology ◽

Matrix Alloy ◽

Micro Milling ◽

Milling Force ◽

Machined Surface ◽

Graphene Nanoflakes ◽

Aluminum Chip ◽

Powder Metallurgy Approach

In this paper, plain aluminum was chosen as matrix alloy and graphene reinforced aluminum alloy composites was successfully prepared via powder metallurgy approach. Micro-milling experiments were conducted to explore the effect of varying graphene nanoflakes (GNFs) content (0.5%, 1.0%, and 1.5% by weight) on the machinability of composites and their machining results were compared with that of plain aluminum. Chip morphology, milling force, and machined surface morphology were used as the machinability measures. Experiment results showed that when the content of GNFs is less than 1.5%, the grain refinement of GNFs plays a major role. The hardness and density of the composites are increased. When the content of GNFs is more than 1.5%, the agglomeration phenomenon is obvious, which reduces the hardness and density of the composites. Micro-milling results show that the milling force is the highest when the GNFs content is 1%, and curling degree of chips increased as FPT increase for a certain content of graphene of composites. Furthermore, when the content of GNFs in composites is more than 1%, the surface roughness of milling grooves is greatly improved, which may be related to the lubrication of graphene and the formation of continuous chips.

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