Chip Forming Temperature on Micro Cutting (1st Report): Measurement of Tool Tip Temperature by Infrared Radiation Pyrometer with Optical Fiber

摘要

A temperature at the tip of a conical cutting tool is measured immediately after micro chip forming using an infrared radiation pyrometer with an optical fiber. The fundamental structure of this pyrometer is that the infrared flux radiated from the tip of the conical cutting tool after cutting is accepted and transmitted to an infrared detector InSb by an optical fiber. The measurement accurancy when applying the pyrometer to the experiment is investigated theoretically. The temperature at the tip of the conical tool at various cooling times after cutting is measured using this pyrometer. A carbon steel and a tungsten are used as workpieces. A cooling characteristic of the tool is analyzed by heat transfer theory. Applying the theoretical results to the experimental results, the temperature of the tip of the conical tool just after cutting is estimated to be 1500°C for carbon steel and 2400°C for tungsten; 1500°C is almost equal to the melting point of carbon steel.