| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a method and an apparatus for heat treatment of a recessed hole for reliably executing the heat treatment to the inner part of the recessed hole having a comparatively small diameter and closed at the bottom part. SOLUTION: In the heat treatment method of the inner part of a recessed hole 4 having an inner diameter of e.g. <=12 mm and a closed bottom surface (bottom part) 6 in an article 1 to be treated, an electric conductive tube 12 is inserted in an almost concentrical state with an interval 9 into the recessed hole 4, and cooling medium W is circulated into the hollow part 11 of the electric conductive tube 12. Further, the contacting part 14 at the tip part 13 of the tube 12 is brought into face contact with the bottom surface 6 of the recessed hole 4 and an electric conductive part 28 is brought into contact with the surface 2 of the article 1 located adjacent to the opening part 8 of the recessed hole 4. Then, a high frequency current is supplied along the inner peripheral surface of the recessed hole 14 and the surface of the electric conductive tube 12 through the base end 15 of the electric conductive tube 12 and the electric conductive part 28.</p> |
