Heat treatment apparatus and heat treatment method
AssigneeJtekt Corporation
InventorsWataru YOSHIDA, Towako MATSUI, Katsuhiko KIZAWA, Takashi SADA, Tsuyoshi MIKAMI
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Abstract
A heat treatment apparatus that thermally treats an annular workpiece formed of a steel material by inductively heating the workpiece includes a treatment tank in which the workpiece is set and thermally treated, a holding portion that holds the workpiece at a predetermined position, an induction heating coil that surrounds the workpiece to inductively heat the workpiece, and a cooling medium that cools surfaces of the workpiece during the induction heating of the workpiece.
Claims20
A heat treatment apparatus that thermally treats an annular workpiece formed of a steel material by inductively heating the workpiece, the heat treatment apparatus comprising:
- a treatment tank in which the workpiece is set and thermally treated;
- a holding portion that holds the workpiece at a predetermined position;
- an induction heating coil that surrounds the workpiece to inductively heat the workpiece;
- and
- a cooling medium that cools surfaces of the workpiece during the induction heating of the workpiece.
A heat treatment method for thermally heating a workpiece formed of high carbon chromium bearing steel, the heat treatment method comprising:
- (A) quenching the workpiece;
- and
- (B) tempering the quenched workpiece, wherein
- in (B), the quenched workpiece is inductively heated with a tempering time of 20 seconds or shorter such that a surface temperature of the workpiece is at least 40° C. lower than an internal temperature of the workpiece.
Dependencies are inferred from the claim text.