Other than in grinding, diamond has far fewer limitations when machining steel by honing. This can be explained by the low cutting speeds, cooling and lubrication conditions in honing, which tend to suppress the reaction between diamond and workpiece materials with carbon affinity [KOPP81].
2.3.4.2 Dressing Technology
Natural diamonds of high purity are commonly used in dressing tools [ODON76, KAIS97, SEN02]. In addition, synthetic diamond logs are common in dressing technology. Mono-crystalline diamonds (MCD) have the advantage of keeping their geometry despite of wear [COEL00, LIER02]. Depending on their orientation, only the properties of one crystal plane are present. In polycrystalline diamonds (PCD), the single diamond crystals are arranged in a Co-matrix, so that the hardness anisotropy of each crystal is equalized. PCD logs are quasi isotropic and have no preferred direction of mechanical properties [LIER02, SEN02]. Sometimes dressing tools with PCD logs are called “geometrically defined dressing tools” because of
their uniform wear behavior [MINK88]. The second polycrystalline dressing log material CVD diamond consists of diamond micro-crystals that grew together without binder [MARI04].
2.3.4.3 Diamond Powder
Micron diamond powder is widely used in suspension for lapping and polishing, as fine abrasive in bonded tools, and as loose abrasive in die stone production, gem stone polishing, and jewel bearing manufacture [HERB81]. Smaller grits have normally higher toughness, due to their lower number of defects [FIEL81]. Diamond performance is determined by grit shape, type, number of inclusions, cracks, and structural defects [SEN91]. Grit surface roughness and grit morphology define bonding adherence [BAIL02]. Diamonds are etched to roughen their surface or are coated with metallic deposits to optimize bonding retention [MARI04].