Optimization of Precision Grinding Parameters of Silicon for Surface Roughness Based on Taguchi Method

2011 ◽  
Vol 264-265 ◽  
pp. 997-1002 ◽  
Author(s):  
Alao Abdur-Rasheed ◽  
Mohamed Konneh

Silicon being a typical hard-brittle material is difficult to machine to a good surface finish. Although ductile-mode machining (DMM) is often employed to machine this advanced material but this technique requires the use of expensive ultra-precision machine tools therefore limiting its applicability. However, by proper selection of grinding parameters, precision grinding which can be performed on conventional machine tools can be used to generate massive ductile surfaces thereby reducing the polishing time and improving the surface quality. Precision grinding should be planned with reliability in advance and the process has to be performed with high rates of reproducibility. Therefore, this study investigated the effect and optimization of grinding parameters using Taguchi optimization technique during precision grinding of silicon. Experimental studies were conducted under varying depths of cut, feed rates and spindle speeds. An orthogonal array (OA), signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) were employed to find the minimum surface roughness value and to analyze the effect of the grinding parameters on the surface roughness. Confirmation tests were carried out in order to illustrate the effectiveness of the Taguchi method. The results show that feed rate mostly affected the surface roughness. The predicted roughness (Ra) of 34 nm was in agreement with the confirmation tests. Massive ductilestreaked surface was also found corresponding to the minimal surface finish determined from the optimal levels.

2014 ◽  
Vol 68 (4) ◽  
Author(s):  
M. S. Said ◽  
J. A. Ghani ◽  
R. Othman ◽  
M. A. Selamat ◽  
N. N. Wan ◽  
...  

The purpose of this research is to demonstrate surface roughness and chip formation by the machining of Aluminium silicon alloy (AlSic) matrix composite, reinforced with aluminium nitride (AlN), with three types of carbide inserts present. Experiments were conducted at various cutting speeds, feed rates, and depths of cut, according to the Taguchi method, using a standard orthogonal array L9 (34). The effects of cutting speeds, feed rates, depths of cut, and types of tool on surface roughness during the milling operation were evaluated using Taguchi optimization methodology, using the signal-to-noise (S/N) ratio. The surface finish produced is very important in determining whether the quality of the machined part is within specification and permissible tolerance limits. It is understood that chip formation is a fundamental element that influences tool performance. The analysis of chip formation was done using a Sometech SV-35 video microscope. The analysis of results, using the S/N ratio, concluded that a combination of low feed rate, low depth of cut, medium cutting speed, and an uncoated tool, gave a remarkable surface finish. The chips formed from the experiment varied from semi–continuous to discontinuous. 


2019 ◽  
Vol 8 (3) ◽  
pp. 3320-3326

Solar dryers are one of most efficient devices for drying food and other products. These devices are eco-friendly and need solar energy for their operation and which is available freely and abundantly at almost every place. These are simple devices which do not need use any fossil fuel for their operation, which are expensive, exhaustive in nature and are not eco friendly. Several fresh food products and other items are dried for preservation and utilization for longer period of time. In recent times, with the development in this technology, the solar dryers are becoming well equipped with efficiency increasing add-ons which give higher performance. Several experimental studies have been carried out to mitigate the time consumption and increasing the productivity of solar dryers. Optimization of solar dryers is done to increase their workability increasing accuracy and reducing drying time and cost investment. In order to optimize the complete setup several techniques could be used to get the optimum results. In the present work Taguchi optimization technique was applied for experimental analysis of solar dryer which was used to dry potatoes. The results thus obtained showed the best configuration comprising air velocity, air flow and humidity required to dry potatoes


2015 ◽  
Vol 766-767 ◽  
pp. 867-872
Author(s):  
P. Sengottuvel ◽  
V. Palanisamy ◽  
J. Arun ◽  
N.R.R. Anbusagar ◽  
J. Hameed Hussain

In this paper , the parameters of Electrical Discharge Machine (EDM) are investigated during the machining of Inconel 718 by using different sizes of circular Aluminum electrode. Demand for better surface finishes are increasing recently for all materials, the low rigidity and high material removal rate of Inconel alloys offers a challenging task in obtaining better Surface Finish. The analysis of surface characteristics like Surface Roughness (SR) of Inconel 718 material is carried out an excellent surface finish can be obtained by setting the machining parameters at optimum level. Experimentation was carried out by using Taguchi’s L9 orthogonal array under different conditions of parameters. The response of SR is considered for improving the machining efficiency. Optimal combination of parameters was obtained Taguchi Optimization technique. The confirmation experiments results shows that the significant improvement in Surface Finish was obtained. ANOVA have been used to analyze the contribution of individual parameters on Surface Roughness. The experimental result demonstrates that the Taguchi method satisfies the practical requirements.


2018 ◽  
Vol 7 (2.8) ◽  
pp. 10
Author(s):  
A VS Ram Prasad ◽  
Koona Ramji ◽  
B Raghu Kumar

Machining of Titanium alloys is difficult due to their chemical and physical properties namely excellent strength, chemical reactivity and low thermal conductivity. Traditional machining of such materials leads to formation of continuous chips and tool bits are subjected to chatter which leads to formation of poor surface on machined surface. In this study, Wire-EDM one of the most popular unconventional machining process which was used to machine such difficult-to-cut materials. Effect of Wire-EDM process parameters namely peak current, pulse-on- time, pulse-off-time, servo voltage on MRRand SR was investigated by Taguchi method. 0.25 mm brass wire was used in this process as electrode material. A surface roughness tester (Surftest 301) was used to measure surface roughness value of the machined work surface. A multi-response optimization technique was then utilized to optimize Wire-EDM process parameters for achieving maximum MRR and minimum SR simultaneously.


2021 ◽  
Author(s):  
Sonia Ezeddini ◽  
Wajdi Rajhi ◽  
Mohamed Boujelbene ◽  
Emin Bayraktar ◽  
Sahbi Ben Salem

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.


Author(s):  
Prosun Mandal

This chapter aims to optimize centreless grinding conditions using the Taguchi method for minimizing surface roughness. The grinding operation has been performed according to the L9 orthogonal array in a centreless grinding process. The centreless grinding experiments are carried out on the crane-hook pin of C40 steel. The analysis of variance (ANOVA) and computation of signal to noise (S/N) ratio are adopted to determine the influence of grinding parameters (depth of cut [µm], regulating wheel speed [rpm], and coolant valve opening) on surface roughness. The depth of cut (µm) is found to be the most significant among the grinding parameters on the surface roughness. The signal to noise (S/N) ratio was calculated based on smaller the best criteria. The lower level of depth of cut, medium level of regulating wheel speed, and higher-level coolant valve opening is found to be optimal grinding condition according to the mean response and signal to noise (S/N) ratio.


Author(s):  
Hui-Qun Chen ◽  
Qing-Hui Wang

Based on the Z-map model of a workpiece and the dynamic cutting forces model of peripheral milling in which the regenerative effect of tool radial runout and axial drift are considered, a model for the prediction of surface topography in peripheral milling operations is presented. According to the stability lobe diagram obtained by the zero-order analytical method, the relationship between spindle speed and surface topography, the tool radial runout, and the axial drift following the chatter are studied. The results show that a stable cutting status but a poor surface finish is obtained at the spindle speeds at which the dominant frequency of the milling system is integral multiples of the selected machining frequency, and a stable cutting status with a good surface finish can be obtained near and on the left side of the resonant spindle speeds determined by the predicted stability lobe diagram. The motion equations of any tooth end mill for peripheral milling are established, and these equations are based on the transformation matrix and the vector operation principle of motion-homogeneous coordinates. In addition, the simulation algorithm and the system of surface topography generated in peripheral milling are given based on the Z-map model. Cutting tests are carried out, and good agreement between the measured surface topographies and the topographies predicted by the model in this study is found in terms of their shape, magnitude, feed mark, profile height of cross-section, and surface roughness. The simulation results show that the milling surface roughness increases with the increase in feed per tooth, which further shows that this simulation system has high credibility. Thus, the simulation and experimental results can provide some practical instructions for the actual peripheral milling in determining the optimal machining conditions.


2011 ◽  
Vol 291-294 ◽  
pp. 810-815 ◽  
Author(s):  
Qi Wu ◽  
Jun Wang

An experimental study of the pulsed laser milling process for a sintered polycrystalline diamond is presented. The characteristics and quality of the cavities machined with a Yd laser under different pulse energies, pulse overlaps, scan overlaps and numbers of passes are discussed, together with the effects of these parameters on the cavity profile, depth of cut and surface roughness. A statistical analysis is also presented to study the relationship between the process parameters and surface roughness. It shows that the optimum pulse overlap and pulse energy may be used to achieve good surface finish, whereas scan overlap and number of passes can be selected to improve the depth of cut without much effect on the surface finish.


2006 ◽  
Vol 304-305 ◽  
pp. 8-13 ◽  
Author(s):  
T. Jin ◽  
D.J. Stephenson

Optical surface finish below Ra 10nm can be achieved on a ‘Tetraform C’ grinder of ultra-high stiffness, when grinding a low alloy steel with or without the help of ELID (electrolytic in process dressing). Surface roughness generation modelling has been carried out to predict thepossible surface roughness values. Efforts have been made to transfer the process knowledge to different grinding mode using a rigid 5-axis Edgetek CNC grinder. The effects of material removal rate and grit size and also that of spark out passes on the surface roughness generated have been investigated.


1999 ◽  
Vol 121 (4) ◽  
pp. 811-814 ◽  
Author(s):  
A. Felix ◽  
S. N. Melkote

Magnetic chucks are commonly used for workholding in precision grinding and turning of ferromagnetic materials. The workholding force produced by the chuck is strongly influenced by the texture and form of the workpiece surface in contact with the chuck surface. This paper presents the results of an experimental investigation into the effects of workpiece surface flatness, finish, and texture on the normal and frictional workholding forces produced by a radial 4-pole electromagnetic chuck. Ring shaped case-hardened steel specimens were used in the experiments. The results show that the normal holding force decreases with increasing flatness deviation. The effect of surface roughness on the normal holding force was found to be small compared to the effect of flatness but significantly impacts the tangential holding force. The workpiece surface texture was also found to have an effect on the workholding forces.


Sign in / Sign up

Export Citation Format

Share Document