| mond tool is commonly used in micro-machining as it | | | | cryongenically cooled chamber. However, these |
| can withstand the micro hardening of the workpiece | | | | methods require costly equipment modification and |
| surface during micro-machining. This micro-hardening | | | | restrict direct supervision of the micro-cutting process. |
| creates enough resistance to break the tool bit easily | | | | The latest breakthrough came when the diamond tool |
| in micro milling, but not a diamond tool. Micro-machining | | | | was subject to ultrasonic vibration during micro-cutting. |
| using diamond tool could be performed at high speeds | | | | It has been shown that a diamond tool subject to |
| and generally fine speeds to produce good surface | | | | ultrasonic vibration can cut the steel well enough to |
| finish such as mirror surfaces and high dimensional | | | | produce a mirror surface finish with acceptable tool life. |
| accuracy in non-ferrous alloys and abrasive | | | | The ultrasonic vibration at the diamond tool tip allows |
| non-metallic materials. | | | | the tool face to cool down considerably during the |
| However, if a diamond tool were to be used to cut | | | | cutting process and delays the chemical reaction |
| steel, one of the most common engineering materials | | | | between the diamond tool and the steel workpiece. As |
| used in industries, the diamond tool will face severe tool | | | | a result, the diamond tool life is increased by a few |
| wear. While diamond only softens at 1350 degree | | | | hundred times. |
| Celsius and melts at 3027 degree Celsius, and is also | | | | For example, a single crystal diamond tool with |
| the hardest material in the world, it has a weakness. | | | | feedrate 5 micron/revolution, cutting speed zero to 5m |
| Diamond succumbs to graphitization, which means that | | | | min and depth of cut 10 micron was attached to a |
| it will change its crystal structure to graphite crystal | | | | ultrasonic vibration generator so that the diamond tool |
| structure at 200 degree Celsius in the presence of a | | | | tip vibrated about 4 microns while it was used to cut |
| catalyst metal such as carbon steel and alloys with | | | | stainless steel. The mirror surface finish of the cut steel |
| titanium, nickel and cobalt. | | | | surface was measured at 8 nm Ra! |
| There have been various attempts to improve the tool | | | | With more and more machining companies moving into |
| life of the diamond tool while cutting steel so as to | | | | the niche micro machining field, such ultrasonic vibration |
| improve the efficiency and profitability of this operation. | | | | assisted cutting can only help the progressive |
| Such processes include micro-cutting the steel | | | | company to achieve process leadership and innovative |
| workpiece in a carbon-rich gas chamber as well as a | | | | differentiation. |