cutting tool can be made with natural materials

single-crystal diamond, synthetic single crystal diamond, chemical vapor deposition (CVD) diamond films, synthetic polycrystalline diamond composite tablets.
A natural single crystal diamondNatural single crystal diamond is a single crystal anisotropic. Hardness HV9000-10000, is the hardest substance in nature. This material is excellent wear  diamond blade circular saw resistance, the cutting tool can be made longer maintain dimensional stability, and therefore has a very long tool life.Natural diamond tool edge can be machined to extremely sharp. Can be used to make ophthalmology and neurosurgery scalpel; contact lenses can be used for machining surfaces; can be used for cutting optical glass fibers; used for processing gold, platinum jewelry patterns; most important use is the high-speed super-finishing non-ferrous metals and their alloys. Such as aluminum, gold, babbitt, beryllium copper, copper and so on. Produced with a natural diamond super finishing tool tip arc portion which under the microscope at 400-fold defect, the polygon mirror for processing aluminum alloy, oxygen-free laser mirror, gyroscopes, recorder drum and  wet saw blades so on. Performance can be achieved roughness Ra (0.01-0.025) μm.
 Poor natural diamond material toughness, flexural strength is very low, only (0.2-0.5) Gpa. Poor thermal stability, the temperature reaches 700 ℃ -800 ℃ will be lost when the hardness. Carbonization temperature will be higher. In addition, its strong affinity with iron generally not suitable for production of steel.
2, single crystal synthetic diamond
Single crystal synthetic diamond as a tool material, can buy on the market there are currently De Beers (DE-BEERS) the production of industrial grade single crystal diamond material. This hss drill bits  material hardness slightly lower than natural diamond. Other properties are comparable with the natural diamond. Because after artificial, orientation and size of its cleavage becomes controllable and unity. With the development of high pressure technology, the maximum size of single crystal synthetic diamond can already do 8mm. Since this material has a relatively good consistency and lower prices, so widespread attention. As an alternative to natural diamond of the new material, the application of synthetic single crystal diamond will have a big development.