Sliding system

Abstract

A sliding system includes a pair of sliding members having opposing sliding surfaces adapted to move relative to each other, and a lubricating oil interposed between the opposing sliding surfaces. Here, at least one of the sliding surfaces is a covered surface covered with a specific chromium nitride film. The lubricating oil contains an oil-soluble molybdenum compound formed of a molybdenum dialkyldithiocarbamate. In the chromium nitride film, when an amount of atoms constituting the entire chromium nitride film is set as 100 atom %, there is 32 atom % to 47 atom % of N, the balance is Cr, and a relative area which is an area ratio of the (111) plane with respect to the (200) plane obtained when the chromium nitride film is analyzed by X-ray diffraction is 20% to 30%.

What is claimed is: 
     
         1 . A sliding system including a pair of sliding members having opposing sliding surfaces adapted to move relative to each other and a lubricating oil interposed between the opposing sliding surfaces,
 wherein at least one of the sliding surfaces is a covered surface covered with a chromium nitride film,   in the chromium nitride film, when an amount of atoms constituting the entire chromium nitride film is set as 100 atom %, there is N of 32 atom % to 47 atom %, and the balance is Cr, and a relative area which is an area ratio of a (111) plane with respect to a (200) plane obtained when the chromium nitride film is analyzed by X-ray diffraction is 20% to 30%,   the lubricating oil contains a molybdenum dialkyldithiocarbamate which is an oil-soluble molybdenum compound, and   a mass ratio of Mo of the molybdenum dialkyldithiocarbamate with respect to the entire lubricating oil is 50 ppm to 800 ppm.   
     
     
         2 . The sliding system according to  claim 1 , wherein the mass ratio of Mo of the molybdenum dialkyldithiocarbamate with respect to the entire lubricating oil is 200 ppm to 700 ppm. 
     
     
         3 . The sliding system according to  claim 1 , wherein the chromium nitride film contains Cr 2 N together with CrN. 
     
     
         4 . The sliding system according to  claim 1 , wherein the lubricating oil contains at least one of a phosphorus compound, a sulfur compound, and a nitrogen compound,
 wherein a mass ratio of P of the phosphorus compound with respect to the entire lubricating oil is 200 ppm to 1,500 ppm,   a mass ratio of S of the sulfur compound with respect to the entire lubricating oil is 500 ppm to 3,000 ppm, and   a mass ratio of N of the nitrogen compound with respect to the entire lubricating oil is 200 ppm to 2,000 ppm.   
     
     
         5 . The sliding system according to  claim 1 , wherein the sliding system is a hybrid vehicle internal combustion engine or a drive transmission device including a transmission. 
     
     
         6 . A sliding system including a pair of sliding members having opposing sliding surfaces adapted to move relative to each other and a lubricating oil interposed between the opposing sliding surfaces,
 wherein at least one of the sliding surfaces is a covered surface covered with a chromium nitride film,   in the chromium nitride film, when an amount of atoms constituting the entire chromium nitride film is set as 100 atom %, there is 32 atom % to 47 atom % of N, the balance is Cr and 1 atom % or less of a doping element, and a relative area which is an area ratio of a (111) plane with respect to a (200) plane obtained when the chromium nitride film is analyzed by X-ray diffraction is 20% to 30%,   the lubricating oil contains a molybdenum dialkyldithiocarbamate which is an oil-soluble molybdenum compound, and   a mass ratio of Mo of the molybdenum dialkyldithiocarbamate with respect to the entire lubricating oil is 50 ppm to 800 ppm.