Patent · US Expired

Sliding member

US6149162A · kind A · utility

11Cited by
3References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 22, 1998
Grant dateNov 21, 2000
Priority date
Expiry dateDec 22, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC23C14/0641
  • WIPO fieldSurface technology, coating
  • WIPO sectorChemistry

Abstract

A gas nitrided layer is formed over the entire surface of a piston ring. A physical vapor deposition film of CrN is formed over the gas nitrided layer at the outer circumferential surface. The physical vapor deposition film has oxygen contained in a solid solution state in a crystal structure of CrN in a content of 0.5 to 20 percent by weight, pores dispersed at a rate of 1 to 15 percent within the film and a crystal structure of CrN with a preferred orientation (200) parallel to the surface being covered. The Vicker's hardness of the film is within a range of 1000 to 1800. The physical vapor deposition film of CrN can be formed beneath a wear resistant film covering the outer circumferential surface of the piston ring. The wear resistant film is for instance, a physical vapor deposition film of chromium nitride such as CrN or Cr.sub.2 N.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.