SLIDING MECHANISM

A sliding mechanism of the present invention includes a cylinder bore having a thermally sprayed iron-based coating and includes a piston with a piston ring covered with a hard coating composed mainly of carbon. [0002] The thermally sprayed coating has diamond abrasive grains. [0003] An area ratio of the diamond abrasive grains to a surface of the thermally sprayed coating is 0.3 to 1.8 %, which enables suppressing wear of the piston ring having the hard coating composed mainly of carbon.