Polishing cloths

A polishing cloth residue is bundled into a cube of 1 m on the half-side dimension. It is stored in an environment of 35 °C and the convective heat transfer is very good between the air and the bundle. Experiments show that the cloth residue has the following properties ... 

Whether the GC is mounted or not, the most common polishing procedure involves a series of abrasives used as slurries on a commercial fabric polishing cloth. The as-received electrode or GC piece is first sanded on 600 grit emery paper to remove gross surface defects and impurities. In most cases, each polishing step involves a circular motion for a few minutes, with the objective being uniform roughness over the electrode surface. The sandpaper is followed by... 

The series of grits typically employed is 240, 320, 400, and 600 6/zm diamond paste on nylon polishing cloth and 1/rni, followed by 0.25/un diamond paste on napped cloth., The polishing resin in which the crystal is mounted should be at least 6 mm wider than the crystal so as to minimize rounding of the edges of the crystal. 

Chlorine trifluoride gradually attacks the silver chloride windows of the infrared cell. When the attack is sufficient to cause serious background on the infrared scan, the cell windows are polished best by using a 5% sodium thiosulfate solution on a velvet polishing cloth. 

For the adsorption tests, a sample of silica (Merk) with a specific surface area of 388 m g measured by the BET method was used. The solid specimens used to measure the contact angles were microscope glass slides and pieces of quartz polished using a rotating plate covered with a polishing cloth impregnated with 10 pm diamond polishing particles. 

The thermoelectric properties were measured at room temperature along the direction perpendicular to the pressing direction. The samples with dimensions of 2 X 2 X15 mm and of 4x4x4 mm were cut out of the compound for the measurements of Seebeck coefficient a and thermal conductivity k and of the electrical resistivity p, respectively. Then, their surfaces were polished with a series of SiC polishing papers of up to 2000 and further polished on a polishing cloth impregnated with AI2O3 powders of 0.3 //m size. 

The metal samples, 2x1 1/2 x 1/8 inches, were polished to a mirror finish on a polishing wheel covered with kitten-ear polishing cloth wet with a suspension of Linde alumina (Type B-5125). Each polished metal sample was covered with an evaporated film of the same metal (1000 A. thick) just prior to use. These films were hydrophillic, indicating the absence of organic contamination. 

FIGURE 18.25 SEM image of ceria particles in a modem polishing cloth. 

An example of a modern commercial polishing cloth is shown in Figure 18.25. The pyramids are particles of ceria bound in a polymer on a flexible cloth. This type of fixed abrasive has an advantage over a slurry in that the abrasive is well controlled and can be easily changed/ renewed and there is always a clear channel for the electrolyte to reach the polishing site. 

The low-pass filtering effect of the polishing process is explained by the model presented in Fig. 7. The stiffness of the fibers embedded in the nap of the polishing cloth allows the granules to smooth the surface without changing the basic contour of the workpiece. 

Microcloth is a tough, feltlike, rayon polishing cloth with a low nap marketed by Buehler Ltd., of Lake Bluff, Illinois. Manufacturers and products are listed for reference or to ass ist in locating various products this does not imply Portland Cement Association endorsement or approval. 

Gently coarse polish the mount on Texmet (a low-nap chemotextile polishing cloth) with 6-pm diamond for approximately four minutes. 

Using a thick slurry of 0.3- j,m alumina on Texmet (or equivalent polishing cloth) with polishing oil or propylene glycol as a vehicle. 

Stage micrometer Polishing cloths and powders Adhesive-backed grinding papers... 

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