| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a high frequency induction hardening and tempering method with which the high frequency induction hardened layer and tempered layer can simultaneously be formed and further, even in case of the hardened product having hardness restrained portions at both sides of the hardness needed portions, the hardness restrained portions can be formed by tempering only one time. SOLUTION: This high frequency induction hardening and tempering method is performed, with which a steel-base hardened product 1 provided with the hardened surface layer is prepared and a part of the hardened surface layer is heated to not lower than the A1 transformation point by heating the hardening surface layer in the hardening product 1 with the high frequency induction heating to make the high temperature heating part 42. Further, portions adjoined to the high temperature heating part 42 are heated to lower than the A1 transformation point to make an intermediate temperature heating parts 44, 45 and thereafter, the high temperature heating part 42 is made to the high frequency induction hardened layer by cooling and also, the intermediate temperature heating parts 44, 45 are made to the tempered layer.</p> |
