Method of treating and smoothing sliding surface

A surface treating method of treating a sliding member which slides on a counter member with a surface thereof kept in contact with a surface of the counter member, said surface treating method comprising the steps of:

• pre-finishing said sliding member to a surface with a surface roughness lower than a lower one of 0.2 μmRa and the surface roughness of said counter member;
• blasting pressurized fluid containing particles harder than said surface of said sliding member on said surface of said sliding member after finished by said pre-finishing to finish said sliding member to a surface with a surface roughness ranging approximately 0.02 to 0.7 μmRa;
• and
• penetrating and diffusing an element in a surface layer of said sliding member after finished by said blasting so as to form a hard compound surface layer whose hardness is higher than said surface hardness of said counter member but lower than 1500 Hv.

A surface smoothing method of smoothing surfaces of a sliding member and a counter member which slide on each other with the surfaces thereof kept in contact with each other, said surface smoothing method comprising the steps of

• providing a sliding member by pre-finishing said sliding member to a surface with a surface roughness lower than the surface roughness of said counter member, blasting pressurized fluid containing particles harder than said surface of said sliding member on said surface of said sliding member to finish said sliding member to a surface with a surface roughness ranging approximately 0.01 to 1.0 μmRa, and hardening said surface of said sliding member to surface hardness the surface hardness of said counter member applied in this order, and
• installing said sliding member and said counter member with said surfaces thereof in contact with each other;
• and
• driving said sliding member and said counter member so as to slide on each other for running-in, thereby smoothing said surfaces of said sliding member and said counter member.