Title:
燃料電池用ステンレス鋼材の表面処理方法
Document Type and Number:
Japanese Patent JP4091425
Kind Code:
B2
Abstract:
A method for treating the surface of a stainless steel product for a fuel cell containing, in wt %, 0.15% or less of C, 17 to 36% of Cr, 0.005 to 3.5% of B, which comprises the first step of forming in advance a passive film with an oxidizing acid on the surface of the stainless steel product, the second step of allowing an aqueous acid solution to corrode the passive film, to thereby project one or more of a M23C6 type carbide, a M23(C, B)6 type borocarbide and M2B type boride, which are inclusions having good electroconductivity, the third step of forming a passive coating film with an oxidizing acid on the surface of the steel product except that of the inclusion above projected, and the fourth step of washing with water and drying. The method of treatment allows, without the use of a method requiring a high cost such as gold plating, the improvement in the contact resistance of the stainless steel product for a fuel cell, which results in the retention of excellent characteristics of a stainless steel product over a long period of time.
Inventors:
Teruyuki Otani
Makoto Tsuji
Masao Utsunomiya
Makoto Tsuji
Masao Utsunomiya
Application Number:
JP2002541140A
Publication Date:
May 28, 2008
Filing Date:
November 06, 2001
Export Citation:
Assignee:
Honda motor industry stock company
International Classes:
C23F1/28; C22C38/42; C22C38/44; C22C38/54; C23C22/50; C23C26/00; C23C28/00; C23F1/00; H01M8/02; C22C38/00; C22C38/32; C22C38/58
Domestic Patent References:
| JP6093470A | ||||
| JP2000144461A | ||||
| JP2000303151A | ||||
| JP2000277133A |
Attorney, Agent or Firm:
Suenari Mikio