Sliding Part and Method of Manufacturing the Same

Abstract

There is provided a sliding part in which a surface coverage ratio of copper in the sliding part increases. A bearing which is the sliding part is formed by filling the raw powder into the filling portion of the forming mold, compacting the raw powder to form a powder compact 6, and sintering the powder compact 6. A copper-based raw powder is composed of a copper-based flat raw powder 2 having an average diameter smaller than that of an iron-based raw powder 1 and an aspect ratio larger than that of the iron-based raw powder 1, and a copper-based small-sized raw powder 3 having the average diameter is smaller than that of the copper-based flat raw powder 2. The copper is allowed to segregate at the surface of the sliding part. In the bearing in which the copper-based flat powder 2 segregates at the surface, the surface is covered with the copper-based small-sized raw powder 3 that has emerged on the surface, as well as the copper-based flat raw powder 2, thereby it is possible to increase the surface coverage ratio of copper.

1 . A sliding part formed by sintering a powder compact, which is fabricated by filling an iron-based raw powder and a copper-based raw powder into a filling portion of a forming mold and compacting the raw powders,
 wherein the copper-based raw powder is comprised of a copper-based flat raw powder having an average diameter smaller than that of the iron-based raw powder and an aspect ratio larger than that of the iron-based raw powder; and a copper-based small-sized raw powder having an average diameter smaller than that of the copper-based flat raw powder, and   copper segregates on a surface of the sliding part.   
     
     
         2 . The sliding part according to  claim 1 ,
 wherein a surface coverage ratio of copper is 80% or more.   
     
     
         3 . The sliding part according to  claim 1 ,
 wherein the aspect ratio of the copper-based flat raw powder is 10 or more.   
     
     
         4 . The sliding part according to  claim 2 ,
 wherein a ratio of the copper-based raw powder is 20 to 40% by weight with respect to all raw powders.   
     
     
         5 . A sliding part formed by sintering a powder compact, which is fabricated by filling an iron-based raw powder and a copper-based raw powder into a filling portion of a forming mold and compacting the raw powders,
 wherein the copper-based raw powder is comprised of a copper-based flat raw powder having an average value of a maximum projected area smaller than that of the maximum projected area of the iron-based raw powder and an aspect ratio larger than that of the iron-based raw powder; and a copper-based small-sized raw powder having an average value of a maximum projected area smaller than that of the maximum projected area of the copper-based flat raw powder, and   copper segregates on a surface of the sliding part.   
     
     
         6 . The sliding part according to  claim 5 ,
 wherein a surface coverage ratio of copper is 80% or more.   
     
     
         7 . A method of manufacturing a sliding part comprising;
 filling an iron-based raw powder and a copper-based raw material into a filling portion of a forming mold,   compacting the raw powders to form a powder compact, and   sintering the powder compact;   wherein the copper-based raw powder is comprised of a copper-based flat raw powder having an average diameter smaller than that of the iron-based raw powder and an aspect ratio larger than that of the iron-based raw powder; and a copper-based small-sized raw powder having an average diameter smaller than that of the copper-based flat raw powder, and   copper segregates on a surface of the sliding part.   
     
     
         8 . A method of manufacturing a sliding part comprising;
 filling an iron-based raw powder and a copper-based raw material into a filling portion of a forming mold,   compacting the raw powders to form a powder compact, and   sintering the powder compact;   wherein the copper-based raw powder is comprised of a copper-based flat raw powder having an average value of a maximum projected area smaller than that of the maximum projected area of the iron-based raw powder and an aspect ratio larger than that of the iron-based raw powder; and a copper-based small-sized raw powder having an average value of a maximum projected area smaller than that of the maximum projected area of the copper-based flat raw powder, and   copper segregates on a surface of the sliding part.   
     
     
         9 . The method according to  claim 7 ,
 wherein the aspect ratio of the copper-based flat raw powder is 10 or more.   
     
     
         10 . The method according to  claim 7 ,
 wherein a ratio of the copper-based raw powder is 20 to 40% by weight with respect to all raw powders.