Laser-assisted grinding of reaction-bonded SiC

The article presents the development of a novel laser-assisted grinding (LAG) process to reduce surface roughness and subsurface damage in grinding reaction-bonded silicon carbide (RB-SiC). A thermal control approach is proposed to facilitate the process development, in which a two-temperature model (TTM) is applied to control the required laser power to thermal softening of RB-SiC prior to the grinding operation without melting the workpiece or leaving undesirable microstructural alteration. Fourier’s law is adopted to obtain the thermal gradient for verification. An experimental comparison of conventional grinding and LAG shows significant reduction of machined surface roughness (37%–40%) and depth of subsurface damage layer (22%–50.6%) using the thermal control approach under the same grinding conditions. It also shows high specific grinding energy 1.5 times that in conventional grinding at the same depth of cut, which accounts for the reduction of subsurface damage as it provides enough energy to promote ductile-regime material removal.

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Surface Roughness Identification in End Milling Using Vibration Signals and Fuzzy Clustering

Volume 4A: Dynamics, Vibration, and Control ◽

10.1115/imece2016-68207 ◽

2016 ◽

Author(s):

Issam Abu-Mahfouz ◽

Amit Banerjee ◽

A. H. M. Esfakur Rahman

Keyword(s):

Surface Roughness ◽

Fuzzy Clustering ◽

Wavelet Transforms ◽

Fourier Transforms ◽

End Milling ◽

Cutting Conditions ◽

Depth Of Cut ◽

Cutting Condition ◽

Machined Surface ◽

Vibration Signals

The study presented involves the identification of surface roughness in Aluminum work pieces in an end milling process using fuzzy clustering of vibration signals. Vibration signals are experimentally acquired using an accelerometer for varying cutting conditions such as spindle speed, feed rate and depth of cut. Features are then extracted by processing the acquired signals in both the time and frequency domain. Techniques based on statistical parameters, Fast Fourier Transforms (FFT) and the Continuous Wavelet Transforms (CWT) are utilized for feature extraction. The surface roughness of the machined surface is also measured. In this study, fuzzy clustering is used to partition the feature sets, followed by a correlation with the experimentally obtained surface roughness measurements. The fuzzifier and the number of clusters are varied and it is found that the partitions produced by fuzzy clustering in the vibration signal feature space are related to the partitions based on cutting conditions with surface roughness as the output parameter. The results based on limited simulations are encouraging and work is underway to develop a larger framework for online cutting condition monitoring system for end milling.

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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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Generation mechanism modeling of surface topography in tangential ultrasonic vibration-assisted grinding with green silicon carbide abrasive wheel

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/09544054211040609 ◽

2021 ◽

pp. 095440542110406

Author(s):

Yutong Qiu ◽

Jingfei Yin ◽

Yang Cao ◽

Wenfeng Ding

Keyword(s):

Surface Roughness ◽

Surface Topography ◽

Ultrasonic Vibration ◽

Generation Mechanism ◽

Surface Generation ◽

Depth Of Cut ◽

Abrasive Wheel ◽

Grinding Parameters ◽

Conventional Grinding ◽

Ultrasonic Vibration Assisted Grinding

Tangential ultrasonic vibration-assisted grinding (TUAG) has a wide prospect in machining difficult-to-machine materials. However, the surface generation mechanism in TUAG is not fully recovered. This study proposes an analytical model of the surface topography produced by TUAG. Based on the model, the surface topography and roughness are predicted and experimentally verified. In addition, the influence of the grinding parameters on the surface topography is analyzed. The predicted surface topography well coincides with experimental measurements, and the prediction error in surface roughness Ra by the proposed model is less than 5%. Compared with conventional grinding, TUAG produces a surface with more uniform scratches and surface roughness Ra was reduced by up to 27% with the proper parameters. However, the improvement of surface roughness in TUAG is weakened when grinding speed or depth of cut increases. Moreover, the influence of the ultrasonic vibration amplitude on the surface roughness is not monotonous. With the grinding parameters selected in this study, TUAG with an ultrasonic amplitude of 7.5 μm produces the minimum surface roughness.

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Machining Evaluation of High-Speed Milling for Thin-Wall Machining of Al7075-T651

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.541-542.785 ◽

2014 ◽

Vol 541-542 ◽

pp. 785-791 ◽

Cited By ~ 1

Author(s):

Joon Young Koo ◽

Pyeong Ho Kim ◽

Moon Ho Cho ◽

Hyuk Kim ◽

Jeong Kyu Oh ◽

...

Keyword(s):

Surface Roughness ◽

Surface Integrity ◽

Cutting Forces ◽

High Speed ◽

Surface Condition ◽

Cutting Conditions ◽

Depth Of Cut ◽

Thin Wall ◽

Machined Surface ◽

High Speed Milling

This paper presents finite element method (FEM) and experimental analysis on high-speed milling for thin-wall machining of Al7075-T651. Changes in cutting forces, temperature, and chip morphology according to cutting conditions are analyzed using FEM. Results of machining experiments are analyzed in terms of cutting forces and surface integrity such as surface roughness and surface condition. Variables of cutting conditions are feed per tooth, spindle speed, and axial depth of cut. Cutting conditions to improve surface integrity were investigated by analysis on cutting forces and surface roughness, and machined surface condition.

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EVALUATION OF SURFACE ROUGHNESS PRODUCED BY NANOCUTTING COPPER STRUCTURE USING A LEAST SQUARE MEAN METHOD

Surface Review and Letters ◽

10.1142/s0218625x19500811 ◽

2019 ◽

Vol 27 (01) ◽

pp. 1950081 ◽

Cited By ~ 1

Author(s):

CHUNHUI JI ◽

SHUANGQIU SUN ◽

BIN LIN ◽

TIANYI SUI

Keyword(s):

Surface Roughness ◽

Cutting Speed ◽

Least Square ◽

Depth Of Cut ◽

Real Surface ◽

Roughness Parameters ◽

Machined Surface ◽

Surface Roughness Parameters ◽

3D Surface ◽

3D Surface Roughness

This work performed molecular dynamic simulations to study the 2D profile and 3D surface topography in the nanometric cutting process. The least square mean method was used to model the evaluation criteria for the surface roughness at the nanometric scale. The result showed that the cutting speed was the most important factor influencing the spacing between the peaks, the sharpness of the peaks, and the randomness of the profile. The plastic deformation degree of the machined surface at the nanometric scale was significantly influenced by the cutting speed and depth of cut. The 2D and 3D surface roughness parameters exhibited a similar variation tendency, and the parameters Ra and Rq tended to increase gradually with an increase in the cutting speed and a decrease in the depth of cut. Finally, it is concluded that at the nanometric scale, the 3D surface roughness parameters could more accurately reflect the real surface characteristics than the 2D parameters.

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Investigation of Surface Characteristics and Chip Morphology in High Speed Cutting of Inconel718 Based on SHPB System

Volume 2A: Advanced Manufacturing ◽

10.1115/imece2019-11036 ◽

2019 ◽

Author(s):

Zengqiang Wang ◽

Zhanfei Zhang ◽

Wenhu Wang ◽

Ruisong Jiang ◽

Kunyang Lin ◽

...

Keyword(s):

Surface Roughness ◽

High Speed ◽

Split Hopkinson Pressure Bar ◽

Orthogonal Cutting ◽

Cutting Speed ◽

Surface Profile ◽

Chip Morphology ◽

Depth Of Cut ◽

Machined Surface ◽

High Speed Cutting

Abstract High speed cutting (HSC) technology has the characteristics of high material removal rates and high machining precision. In order to study the relationships between chip morphology and machining surface characteristic in high speed cutting of superalloy Inconel718. High-speed orthogonal cutting experiment are carried out by used a high speed cutting device based on split Hopkinson pressure bar (SHPB). The specimen surfaces and collected chips were then detected with optical microscope, scanning electron microscope and three-dimensional surface profile measuring instrument. The results show that within the experimental parameters (cutting speed from 8–16m/s, depth of cut 0.1–0.5mm), the obtained chips are sawtooth chips and periodic micro-ripple appear on the machined surface. With the cutting speed increases, machining surface roughness is decreases from 1.4 to 0.99μm, and the amplitude of periodic ripples also decreases. With the cutting depth increases, the machining surface roughness increases from 0.96 to 5.12μm and surface topography becomes worse. With the increase of cutting speed and depth of cut, the chips are transform from continues sawtooth to sawtooth fragment. By comparing the frequency of surface ripples and sawtooth chips, it is found that they are highly consistent.

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Multi Objective Optimization of Cutting Parameters in Machining Cellulose Based Hybrid Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.761.287 ◽

2015 ◽

Vol 761 ◽

pp. 287-292

Author(s):

Raja Izamshah ◽

Zainudin Zuraidah ◽

Mohd Shahir Kasim ◽

M. Hadzley ◽

M. Amran

Keyword(s):

Surface Roughness ◽

Feed Rate ◽

Hybrid Composites ◽

Depth Of Cut ◽

Machining Parameters ◽

Multi Objective Optimization ◽

Machining Performance ◽

Machined Surface ◽

Multi Objective ◽

Optimization Of Cutting Parameters

Cellulose based hybrid composites are gaining popularity in the growing green communities. With extensive studies and increasing applications for future advancement, the need for an accurate and reliable guidance in machining this type of composites has increased enormously. Smooth and defect free machined surface are always the ultimate objectives. The present work deals with the study of machining parameters (i.e. spindle speed, feed rate and depth of cut) and their effects on machining performance (i.e. surface roughness and delamination) to establish an optimized setup of machining parameters in achieving multi objective machining performance. Cellulose based hybrid composites consist of jute (a bast fiber) and glass fiber embedded in polyester resins. Response Surface Methodology (RSM) using Box-Behnken Design (BBD) was chosen as the design of experiment approach for this study. Based on that experimental approach, 17 experimental runs were conducted. Mathematical model for each response was developed based on the experimental data. Adequacy of the models were analyzed statistically using Analysis of Variance (ANOVA) in determining the significant input variables and possible interactions. The multi objective optimization was performed through numerical optimization, and the predicted results were validated. The agreement between the experimental and selected solution was found to be strong, between 95% to 96%, thus validating the solution as the optimal machining condition. The findings suggest that feed rate was the main factor affecting surface roughness and delamination .

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Effect of SiC Particles on the Machining of Aluminum/SiC Composite

Materials Science Forum ◽

10.4028/www.scientific.net/msf.626-627.219 ◽

2009 ◽

Vol 626-627 ◽

pp. 219-224 ◽

Cited By ~ 4

Author(s):

Gao Feng Zhang ◽

Yuan Qiang Tan ◽

Bi Zhang ◽

Zhao Hui Deng

Keyword(s):

Surface Roughness ◽

Aluminum Matrix ◽

Volume Ratio ◽

Damage Mechanism ◽

Depth Of Cut ◽

Machining Parameters ◽

Machined Surface ◽

Aluminum Metal ◽

Sic Particles ◽

Average Grain Size

The objective of this study is to experimentally investigate the effect of reinforced SiC particles on the machining of Aluminum/SiC composite (15% volume ratio of SiC particles with average grain size 15m). Aluminum/SiC composite and aluminum metal were milled by a tungsten carbide endmill in this study. Based on the surface observation and surface roughness inspection, it is found that the machining parameters of Aluminum/SiC composite have optimum values, and that the surface roughness of aluminum/SiC composite is smaller than that of aluminum metal. when feedrate and depth of cut are smaller than limited values, satisfactory surface finish can be attainable, however, as the depth of cut and feedrate increases, the microcracks are first initiated at the interface of SiC particles and aluminum matrix, and then periodically macrocracks are formed on the machined surface, The damage mechanism during the machining of aluminum/SiC are discussed in this paper.

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Analysis and Optimization of Cutting Tool Coating Effects on Surface Roughness and Cutting Forces on Turning of AA 6061 Alloy

Advances in Materials Science and Engineering ◽

10.1155/2021/6498261 ◽

2021 ◽

Vol 2021 ◽

pp. 1-12

Author(s):

Mahir Akgün ◽

Fuat Kara

Keyword(s):

Surface Roughness ◽

Mathematical Models ◽

Cutting Force ◽

Feed Rate ◽

Cutting Speed ◽

Depth Of Cut ◽

Dry Cutting ◽

Machined Surface ◽

Tool Coating ◽

Cutting Inserts

The present work has been focused on cutting force (Fc) and analysis of machined surface in turning of AA 6061 alloy with uncoated and PVD-TiB2 coated cutting inserts. Turning tests have been conducted on a CNC turning under dry cutting conditions based on Taguchi L18 (21 × 33) array. Kistler 9257A type dynamometer and equipment have been used in measuring the main cutting force (Fc) in turning experiments. Analysis of variance (ANOVA) has been applied to define the effect levels of the turning parameters on Fc and Ra. Moreover, the mathematical models for Fc and Ra have been developed via linear and quadratic regression models. The results indicated that the best performance in terms of Fc and Ra was obtained at an uncoated insert, cutting speed of 350 m/min, feed rate of 0.1 mm/rev, and depth of cut of 1 mm. Moreover, the feed rate is the most influential parameter on Ra and Fc, with 64.28% and 54.9%, respectively. The developed mathematical models for cutting force (Fc) and surface roughness (Ra) present reliable results with coefficients of determination (R2) of 96.04% and 92.15%, respectively.

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Optimization of compressed air assisted-turning-burnishing process for improving machining quality, energy reduction and cost-effectiveness

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420976661 ◽

2020 ◽

pp. 095440542097666

Author(s):

Trung-Thanh Nguyen ◽

Chi-Hieu Le

Keyword(s):

Surface Roughness ◽

Energy Consumption ◽

Surface Hardness ◽

Compressed Air ◽

Depth Of Cut ◽

Machining Parameters ◽

Machined Surface ◽

Machining Quality ◽

Machining Speed ◽

Burnishing Process

The burnishing process is used to enhance the machining quality via improving the surface finish, surface hardness, wear-resistance, fatigue, and corrosion resistance, and it is mostly used in aerospace, biomedical, and automotive industries to improve reliability and performance of the component. The combined turning and burnishing process is therefore considered as an effective solution to enhance both machining quality and productivity. However, the trade-off analysis between energy consumption, surface characteristics, and production costs has not been well-addressed and investigated. This study presents an optimization of the compressed air assisted-turning-burnishing (CATB) process for aluminum alloy 6061, aimed to decrease the energy consumption as well as surface roughness and to enhance the Vicker hardness of the machined surface. The machining parameters for consideration include the machining speed, feed rate, depth of cut, burnishing force, and the ball diameter. The improved Kriging models were used to construct the relations between machining parameters and the technological response characteristics of the machined surface. The optimal machining parameters were obtained utilizing the desirability approach. The energy based-cost model was developed to assess the effectiveness of the proposed CATB process. The findings showed that the selected optimal outcomes of the depth of cut, burnishing force, diameter, feed rate, and machining speed are 0.66 mm, 196.3 N, 8.0 mm, 0.112 mm/rev, and 110.0 m/min, respectively. The energy consumption and surface roughness are decreased by 20.15% and 65.38%, respectively, while the surface hardness is improved by 30.05%. The production cost is decreased by 17.19% at the optimal solution. Finally, the proposed CATB process shows a great potential to replace the traditional techniques which are used to machine non-ferrous metals.

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