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Assisted Machining Technologies
Published in Helmi Youssef, Hassan El-Hofy, Non-Traditional and Advanced Machining Technologies, 2020
To minimize the surface damage, gentle polishing conditions are required, namely, low levels of controlled force and abrasives not much harder than the work material. A recent development involves the use of a magnetic field to support abrasive slurries in polishing ceramic balls and bearing rollers. A magnetic float polishing technique for finishing ceramic balls was initiated in Japan chiefly by Umehara and Kato (1996). They termed it magnetic fluid grinding (MFG). However, the term magnetic float polishing (MFP) is also used, as this is more a polishing (3-body) process rather than a grinding (2-body, fixed abrasive) operation. In literature, both terms are found.
Metallography and Material Characterization
Published in Zainul Huda, Metallurgy for Physicists and Engineers, 2020
Polishing. Polishing involves the removal of the remaining scratches on the ground specimen so as to produce a smooth lustrous surface required for microscopic examination. Polishing is accomplished by using a polishing machine with rotating polishing discs that are covered with soft cloth impregnated with abrasive particles (alumina powder suspension or diamond paste) and an oily lubricant or water lubricant. In the case of polishing with diamond paste, particles of different grades are used: a coarser polish (with diamond particles 6 µm in diameter), and then a finer polish (with diamond particles 1 µm in diameter) to produce a smooth surface. At each polishing stage, the specimen should be washed thoroughly with warm soapy water to prevent contamination of the next disc. An alcohol rinse should be used in the final polishing stage; drying can be accelerated by using a hot air drier. The polished specimens reflects light like a mirror (see Figure 5.4).
Water Systems for Parenteral Facilities
Published in Sandeep Nema, John D. Ludwig, Parenteral Medications, 2019
Stainless steel finishing itself is an extensive subject and is beyond the scope that can be effectively covered within this chapter. It should be noted that most finishes are mechanically applied, progressively using increasingly finer abrasives, similar in concept to wood sanding. Higher quality finishes typically require the application of electrochemical polishing, or electropolishing, usually over a high-quality mechanical finish. The reverse of plating, electropolishing, also known as chemical machining, removes surface material to create an extremely smooth and attractive finish that may be easier to clean based on the materials in contact with the surface. In addition, electropolishing creates a passive layer on the surface of the stainless steel, increasing its corrosion resistance.
Surface roughness modeling in chemically etched polishing of Si (100) using double disk magnetic abrasive finishing
Published in Machining Science and Technology, 2019
Kheelraj Pandey, Pulak M. Pandey
Mechanical polishing process falls in the category of secondary manufacturing process whose prime objective is to bring out the required surface integrity and surface finish in the work material. The purpose of mechanical polishing is to reduce the peaks existing in the work material and to attain the surface finish to the desired degree of accuracy. Materials with extraordinary and stringent properties are difficult to be finished by conventional machining processes. Silicon wafer, having some stringent properties falls in the category of materials which are difficult to be finished, has been polished under synergetic actions with chemical mechanical polishing (CMP). CMP is a planarization technique which works on the concept of first weakening the atomic bonds in the workpiece by the use of chemical action and thereby removing the material from the workpiece by the use of rotatory mechanical action. Zantye et al. (2004), Luo and Dornfeld (2001) and Zarudi and Han (2003) used CMP process for polishing silicon wafer to improve its planarization, material removal mechanism and the deformity caused, which were useful to evaluate the effectiveness of the CMP process.
Modeling surface roughness for polishing process based on abrasive cutting and probability theory
Published in Machining Science and Technology, 2018
Guilian Wang, Xiaoqin Zhou, Guangwei Meng, Xu Yang
Polishing is an important finishing process to achieve the desired surface quality. Surface roughness is a variable widely used to describe the product quality and in most cases a technical requirement for mechanical products. The process parameters (polishing pressure, tool speed, feed rate, polishing times, etc.) and material parameters (workpiece material, abrasive tool material, grit, etc.) have effects on the surface roughness. It is necessary and meaning to establish accurate surface roughness model and analyze the effect of process parameters on the surface roughness because a key problem for automatic polishing equipment is how to efficiently choose process parameters to obtain ideal surface roughness under various conditions. Many researchers have already done much work about the prediction of surface roughness for these years (Benardos and Vosniakos, 2003; Grandguillaume et al., 2015; Macurova, 2010; Patrikar, 2004; Ukar et al., 2012). In general, there are three categories based on machining theory, experiment and artificial intelligence.
Design and analysis of a compliant polishing manipulator with tensegrity-based parallel mechanism
Published in Australian Journal of Mechanical Engineering, 2021
Wei Zhu, Jiahong Liu, Hanbing Li, Kairong Gu
Polishing is a kind of finishing process after machining to obtain a good surface roughness as well as the form accuracy. In the process, the traditional end-effector is in contact rigidly with an environment (e.g., workpiece), therefore forces and moments on the polishing tool need to be measured and controlled by using force/moment sensors. Depending on the skill and experience from manual work, the axis of the polishing tool should remain normal to the local surface while performing tasks (Dwivedy and Eberhard. 2006Rahimi and Nazemizadeh 2014), and the normal force exerted by the polishing tool should also be constant approximatively. So, the position and attitude of the polishing tool needs to be changed rapidly according to the curvature of the workpiece surface.