Pace Technologies, SIC-2212-400, 12" Premium SiC Abrasive Paper, Plain Backed, 400 / P800 Grit
Features:
SiC is a manufactured abrasive produced by a high-temperature reaction between silica and carbon. It has a hexagonal-rhombohedral crystal structure and a hardness of approximately 2500 HV. It is an ideal abrasive for cutting and grinding metallographic specimens because of its hardness and sharp edges. It is also somewhat brittle and cleaves easily to produce sharp edges (self-sharpening). SiC is an excellent abrasive for maximizing cutting rates while minimizing surface and subsurface damage. For metallographic preparation, SiC abrasives are used in abrasive blades. Bonded or coated abrasive papers of SiC are designed so that the abrasive will have many cutting points (negative abrasive rank angle). This is achieved by aligning the abrasive particles approximately normal to the backing. Note that coated abrasives are not quite coplanar, thus SiC papers produce the maximum efficiency (cut rate, stock removal, and minimal damage) because the abrasive is exposed as the old abrasive breaks down.
Plain-backed papers are the least expensive, however, they require either a double sided adhesive or a paper holding ring. The disadvanatage to using a paper holiding ring is that the mounted specimen cannot track over the edge of the grinding paper. Thus the paper does not break down uniformly and thus can produce over grinding of the mount away from the sample. This artifact results in the polished mount exhibiting a crescent moon which can affect the edge of the speciment. This artifact has also been known as "mooning" or MRD (material removal differential).
