Structure of Piston Ring

Abstract

A structure of a piston ring to be installed in an engine includes a matrix wherein a laminated intermediate layer is formed on a surface of the matrix from hard chromium (Cr), chromium nitride (CrN) and titanium carbide (TiC) in order, and a diamond-like carbon film (DLC) is coated on an outer periphery of the intermediate layer, so that the piston ring is wrapped by a skin with a progressive structure having gradient distribution of hardness. The structure formed from the diamond-like carbon film provides low wear rate and low friction coefficient, while applying a high bonding force to the matrix and making the piston ring have an improved normal service life that meets the related environmental regulations.

What is claimed is: 
     
         1 . A structure of a piston ring, comprising a matrix wherein a laminated intermediate layer is formed on a surface of the matrix from hard chromium (Cr), chromium nitride (CrN) and titanium carbide (TiC) in order, and a diamond-like carbon film (DLC) is coated on an outer periphery of the intermediate layer,
 whereby the piston ring is wrapped by a skin with a progressive structure having gradient distribution of hardness and the structure formed from the diamond-like carbon film provides low wear rate and low friction coefficient, while applying a high bonding force to the matrix and making the piston ring have an improved normal service life that meets related environmental regulations.   
     
     
         2 . A structure of a piston ring, comprising a matrix wherein a laminated intermediate layer is formed on a surface of the matrix from chromium nitride (CrN) and titanium carbide (TiC) in order, and a diamond-like carbon film (DLC) is coated on an outer periphery of the intermediate layer,
 whereby the piston ring is wrapped by a skin with a progressive structure having gradient distribution of hardness and the structure formed from the diamond-like carbon film provides low wear rate and low friction coefficient, while applying a high bonding force to the matrix and making the piston ring have an improved normal service life that meets related environmental regulations.