Title:
CHROMIUM COATING METHOD AND METAL VALVE FOR ENGINE COATED BY THIS METHOD
Document Type and Number:
Japanese Patent JPH0657478
Kind Code:
A
Abstract:
PURPOSE: To provide a valve for an internal-combustion engine having more excellent wear resistance than the coating of hexavalent chromium conventionally used.
CONSTITUTION: In the valve 100 for the internal-combustion engine having a stem 4, the coating of trivalent chromium is electroplated on the stem, and it is heated at about 150°F in the min. for at least 30 min. The electroplating is desirable to execute in the aqueous solution 26 containing the trivalent chromium and boric acid and further, this solution is desirable to have about 2.0 - about 3.0 pH, too. Further, in the solution, stabilizer or conditioner is desirable to be contained, too.
Inventors:
SUTEEBEN ROI SHIYAHIYAMAIYAA
ZUNDARAMU RAKUSHIYUMI NARASHIM
PAURU ANDORUU BUYARUSUKI
ZUNDARAMU RAKUSHIYUMI NARASHIM
PAURU ANDORUU BUYARUSUKI
Application Number:
JP13762993A
Publication Date:
March 01, 1994
Filing Date:
June 08, 1993
Export Citation:
Assignee:
EATON CORP
International Classes:
C25D5/26; C25D3/06; C25D5/50; C25D7/00; F01L3/02; F01L3/04; F02B3/06; (IPC1-7): C25D5/26; C25D5/50; C25D7/00; F01L3/02
Attorney, Agent or Firm:
Wakabayashi Tadashi
Next Patent: TANTALUM PLATING METHOD BY FUSED SALT ELECTROLYSIS