| 摘要 |
PURPOSE:To dissolve stress concentration without reducing the strength of a substrate by carrying out polishing after forming a linear impression in the radial direction between the tips of a disc-shaped substrate made of steel on the outer periphery of which a plurality of superhard tips are soldered. CONSTITUTION:When a circular saw cutter is soldered, a cemented carbide tip 2, solder 3, and the steel of a substrate 1 are put into high temperature, and expanded with each characteristic thermal expansion rate, and in cooling, the stress concentration is generated at the soldered part on the basis of the difference of the thermal expansion rate, and a tip 2 having the smallest thermal expansion rate is applied with a pulling force. The stress concentration can be dissolved by forming an impression 5. Therefore, no warp due to stress concentration is generated on the circular saw cutter, and also the tip 2 is not applied with a pulling force due to the stress concentration, and the superior polishing is permitted. Further, though the tip 2 possesses a high resistance force for a compression force, the tip 2 possesses weak property for a pulling force. Therefore, when polishing is performed in the stress concentration state, a crack is generated on the tip 2 applied with pulling action, but the polishing free from crack is permitted because polishing is carried out after the stress concentration is dissolved by the impression 5. |
