Analytical Study on Mechanism of Electrolysis and Plasma Polishing

2012 ◽  
Vol 472-475 ◽  
pp. 350-353 ◽  
Author(s):  
Ji Wang ◽  
Lai Chun Suo ◽  
Li Li Guan ◽  
Yi Li Fu

Electrolysis and plasma polishing(EPP) is a new “green” technique that can efficiently polish metal workpieces and provide high-quality surface of the workpieces. In this paper, mechanism of EPP and why metal parts can be polished by EPP are expounded on by Streamer theory. EPP is a dynamic process consisting of oxidation and discharge. A precondition of EPP is that the removal rate of discharge is faster than oxidation. It is deduced from the mechanism and demonstrated experimentally that the material removal rate is direct proportion to the electric current density.

2018 ◽  
Author(s):  
Zewei Yuan ◽  
Kai Cheng ◽  
Yan He ◽  
Meng Zhang

The high quality surface can exhibit the irreplaceable application of single crystal silicon carbide in the fields of optoelectronic devices, integrated circuits and semiconductor. However, high hardness and remarkable chemical inertness lead to great difficulty to the smoothing process of silicon carbide. Therefore, the research presented in this paper attempts to smooth silicon carbide wafer with photocatalysis assisted chemical mechanical polishing (PCMP) by using of the powerful oxidability of UV photo-excited hydroxyl radical on surface of nano-TiO2 particles. Mechanical lapping was using for rough polishing, and a material removal model was proposed for mechanical lapping to optimize the polishing process. Several photocatalysis assisted chemical mechanical polishing slurries were compared to achieve fine surface. The theoretical analysis and experimental results indicate that the material removal rate of lapping process decreases in index form with the decreasing of abrasive size, which corresponds with the model developed. After processed with mechanical lapping for 1.5 hours and subsequent photocatalysis assisted chemical mechanical polishing for 2 hours, the silicon carbide wafer obtains a high quality surface with the surface roughness at Ra 0.528 nm The material removal rate is 0.96 μm/h in fine polishing process, which is significantly influenced by factors such as ultraviolet irradiation, electron capture agent (H2O2) and acidic environment. This combined method can effectively reduce the surface roughness and improve the polishing efficiency on silicon carbide and other hard-inert materials.


2014 ◽  
Vol 518 ◽  
pp. 19-24 ◽  
Author(s):  
Ying Chien Tsai ◽  
Guang Miao Huang ◽  
Jun Hong Chen ◽  
Inn Chyn Her

The surfaces of the microlenses at the conical end-faces of optical fibers require high quality to keep the best performance of laser beam delivery. The polishing parameters play an important role to get the best quality of the microlenses. Most of the past researches study on the polishing parameters of flat surfaces. In this study, the polishing area of the conical end-face of the optical fiber is varied during fabrication. The relation between removed volume and removed thickness is built to determine the material removal rate. An experiment is carried out and the results show that the first two spinning turns are much effective for polishing under the parameters of the experiment.


2017 ◽  
Vol 739 ◽  
pp. 157-163
Author(s):  
Guan Fu Lin ◽  
Ming Yi Tsai ◽  
Chiu Yuan Chen

This paper presents a combined diamond-impregnated lapping plate for single crystal silicon carbide (SiC) to improve the material removal rate due to SiC having very low material removal rate. Three different dimaond shapes were prepared: (1) "sharp," a sharp-edged diamod; (2) "blocky," a high quality crystalline diamond; (3) "oxidized diamond". The diamonds were manufactured by using high temperature heating method in a furnace to induce diamond oxidation resulting in improvement of Ra and sharpness of the diamonds. Three combined diamond-impregnated lapping plates were fabricated using the above mentioned diamond shapes with diamond size of 6μm. The surface roughness and removal rate of the SiC lapping with these plate were investigated. Experimental results showed that the average material removal rate (MRR) of oxidized diamond is higher than that of the other diamond shapes. The MRR of oxidized diamond for C-face and Si-face SiC are 4.72μm/hr and 6.26μm/hr, respectively. It is found that the surface roughness (Ra) of oxidized diamond for C-face and Si-face are 7.547nm and 8.06nm, respectively. This indicates that the combined diamond-impregnated lapping plate can be effectively used for SiC machining.


2007 ◽  
Vol 329 ◽  
pp. 711-718 ◽  
Author(s):  
Seok Woo Lee ◽  
S.H. Nam ◽  
Hon Jong Choi ◽  
E.G. Kang ◽  
K.Y. Ryu

Today, the trend in die and mold manufacturing is to pursue high-quality surface topology using high-speed finish milling operation. This paper presents a new approach to optimize machining conditions according to the required material removal rate (MRR), focusing on obtaining a high-quality surface. In this approach, the prediction model of surface roughness using the 2-staged artificial neural network (ANN) is employed for the objective function. Furthermore, an additional surface quality criterion is also used for the optimization problem using the genetic algorithm. It has been investigated that optimized machining conditions can be selected to obtain the high-quality surface within allowable reliability while maintaining a high-quality surface, under the given desired MRR.


2010 ◽  
Vol 148-149 ◽  
pp. 19-24
Author(s):  
Chao Hui Zhang ◽  
Hong Lei ◽  
Xiao Li Hu

Slurry preparation is of paramount importance in chemical mechanical planarization (CMP) process. It couples the combination effects of chemical and mechanical ones. In this paper, the characteristics of the slurry particles used in CMP are firstly modeled, which includes the size and the concentration with primary priority. And then, the model is validated by experiments during hard disk wafer polishing. The slurry prepared contributes to a high quality hard disk surface processed with CMP, which leads to low waviness Wa and roughness Ra with suitable material removal rate (MRR) as well. The study will surely lay a feasible foundation to the CMP mechanism.


Author(s):  
Amritpal Singh ◽  
Rakesh Kumar

In the present study, Experimental investigation of the effects of various cutting parameters on the response parameters in the hard turning of EN36 steel under the dry cutting condition is done. The input control parameters selected for the present work was the cutting speed, feed and depth of cut. The objective of the present work is to minimize the surface roughness to obtain better surface finish and maximization of material removal rate for better productivity. The design of experiments was done with the help of Taguchi L9 orthogonal array. Analysis of variance (ANOVA) was used to find out the significance of the input parameters on the response parameters. Percentage contribution for each control parameter was calculated using ANOVA with 95 % confidence value. From results, it was observed that feed is the most significant factor for surface roughness and the depth of cut is the most significant control parameter for Material removal rate.


Author(s):  
A. Pandey ◽  
R. Kumar ◽  
A. K. Sahoo ◽  
A. Paul ◽  
A. Panda

The current research presents an overall performance-based analysis of Trihexyltetradecylphosphonium Chloride [[CH3(CH2)5]P(Cl)(CH2)13CH3] ionic fluid mixed with organic coconut oil (OCO) during turning of hardened D2 steel. The application of cutting fluid on the cutting interface was performed through Minimum Quantity Lubrication (MQL) approach keeping an eye on the detrimental consequences of conventional flood cooling. PVD coated (TiN/TiCN/TiN) cermet tool was employed in the current experimental work. Taguchi’s L9 orthogonal array and TOPSIS are executed to analysis the influences, significance and optimum parameter settings for predefined process parameters. The prime objective of the current work is to analyze the influence of OCO based Trihexyltetradecylphosphonium Chloride ionic fluid on flank wear, surface roughness, material removal rate, and chip morphology. Better quality of finish (Ra = 0.2 to 1.82 µm) was found with 1% weight fraction but it is not sufficient to control the wear growth. Abrasion, chipping, groove wear, and catastrophic tool tip breakage are recognized as foremost tool failure mechanisms. The significance of responses have been studied with the help of probability plots, main effect plots, contour plots, and surface plots and the correlation between the input and output parameters have been analyzed using regression model. Feed rate and depth of cut are equally influenced (48.98%) the surface finish while cutting speed attributed the strongest influence (90.1%). The material removal rate is strongly prejudiced by cutting speed (69.39 %) followed by feed rate (28.94%) whereas chip reduction coefficient is strongly influenced through the depth of cut (63.4%) succeeded by feed (28.8%). TOPSIS significantly optimized the responses with 67.1 % gain in closeness coefficient.


2020 ◽  
Vol 38 (9A) ◽  
pp. 1406-1413
Author(s):  
Yousif Q. Laibia ◽  
Saad K. Shather

Electrical discharge machining (EDM) is one of the most common non-traditional processes for the manufacture of high precision parts and complex shapes. The EDM process depends on the heat energy between the work material and the tool electrode. This study focused on the material removal rate (MRR), the surface roughness, and tool wear in a 304 stainless steel EDM. The composite electrode consisted of copper (Cu) and silicon carbide (SiC). The current effects imposed on the working material, as well as the pulses that change over time during the experiment. When the current used is (8, 5, 3, 2, 1.5) A, the pulse time used is (12, 25) μs and the size of the space used is (1) mm. Optimum surface roughness under a current of 1.5 A and the pulse time of 25 μs with a maximum MRR of 8 A and the pulse duration of 25 μs.


Sign in / Sign up

Export Citation Format

Share Document