| (19) |
 |
|
(11) |
EP 0 787 817 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
27.01.1999 Bulletin 1999/04 |
| (43) |
Date of publication A2: |
|
06.08.1997 Bulletin 1997/32 |
| (22) |
Date of filing: 17.04.1996 |
|
|
| (84) |
Designated Contracting States: |
|
DE FR GB IT NL SE |
| (30) |
Priority: |
30.01.1996 JP 14365/96
|
| (71) |
Applicant: DAIDO HOXAN INC. |
|
Sapporo-shi,
Hokkaido 060 (JP) |
|
| (72) |
Inventors: |
|
- Tahara, Masaaki
Takatsuki-shi,
Osaka 569 (JP)
- Senbokuya, Haruo
Tondabayashi-shi,
Osaka 584 (JP)
- Kitano, Kinzo
Kawachinagano-shi,
Osaka 586 (JP)
- Hayashida, Tadashi
Nishinomiya-shi,
Hyogo 662 (JP)
|
| (74) |
Representative: Wakerley, Helen Rachael |
|
Reddie & Grose,
16 Theobalds Road
London WC1X 8PL
London WC1X 8PL (GB) |
|
| |
|
| (54) |
Method of carburizing austenitic stainless steel and austenitic stainless steel products
obtained thereby |
(57) A method of carburizing austenitic stainless steel comprising the steps of holding
austenitic stainless steel in a fluorine- or fluoride-containing gas atmosphere with
heating prior to carburizing and carburizing the austenitic stainless steel at a temperature
not more than 680°C wherein said austenitic stainless steel is stable austenitic stainless
steel having 1 to 6 weight % molybdenum or 13 to 25 weight % chromium, wherein a carburized
hard layer having corrosion resistance superior to base material forms and austenitic
stainless steel products obtained thereby.