To enhance the abrasion resistance and peel resistance of a steel member to be used in a heavy load environment.
This surface treatment method comprises: nitriding the steel member to form a chemical compound layer of N and Fe on its outermost surface and form a nitrogen-diffused layer 12 at the bottom of the compound layer; and denitriding the steel member at a predetermined treatment temperature in a denitriding gas atmosphere. The denitriding treatment causes a denitrification reaction (reaction of removing N from the compound layer consisting of -Fe2-3N or γ'-Fe4N formed during the nitriding treatment) in the compound layer. Then, the outermost surface of the steel member is composed of a denitrided layer 11 having high hardness, and further high peel resistance and abrasion resistance, because in the denitrided layer 11, N has been removed from the compound layer formed during the nitriding treatment.
KAWAKAMI TOSHIO
NAKAMURA HISAO
SUZUKI HIROYOSHI
TSUGE TAKAKI
DOWA MINING CO
| JPS404453B1 | ||||
| JPH04289117A | 1992-10-14 | |||
| JPH06116607A | 1994-04-26 | |||
| JPH09235651A | 1997-09-09 | |||
| JPH0328317A | 1991-02-06 | |||
| JPS51111416A | 1976-10-01 | |||
| JPH07173603A | 1995-07-11 | |||
| JPH0754050A | 1995-02-28 | |||
| JPH04157115A | 1992-05-29 | |||
| JPH10259421A | 1998-09-29 | |||
| JPH09143618A | 1997-06-03 |
Takao Ito
Jiro Higuchi
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