Aluminum-based bearing alloy

Abstract

The present invention has been made by the fact that the wettability with lubricant increases when tin grains are broken within a certain range. In an aluminum-based bearing alloy containing from 2 to 20 mass % of tin, the tin grains in a sliding surface have a size not less than 20 μm 2 but not more than 50 μm 2 expressed in region partitioned areas of the tin grains measured in accordance with a region partitioning method.

1 . An aluminum-based bearing alloy containing not less than 2 mass % but not more than 20 mass % of tin,
 wherein tin grains in a sliding surface have a size not less than 20 μm 2  but not more than 50 μm 2  expressed in an average region partitioned area of the tin grains measured by a region partitioning method.   
   
   
       2 . The aluminum-based bearing alloy according to  claim 1 , further containing an intermetallic compound composed of aluminum and at least two other elements,
 wherein the number of intermetallic compound grains having a size smaller than 1 μm is not less than 300 in an observation area of 20 μm×15 μm.   
   
   
       3 . The aluminum-based bearing alloy according to  claim 2 ,
 wherein the at least two other elements that form the intermetallic compound in combination with aluminum is selected from the group consisting of manganese, vanadium, chromium, cobalt, iron, nickel, tungsten, titanium, and zirconium, a total amount of the selected elements being not less than 0.01 mass % but not more than 3 mass %.   
   
   
       4 . The aluminum-based bearing alloy according to  claim 1 ,
 further containing not less than 2 mass % but not more than 6 mass % of silicon.   
   
   
       5 . The aluminum-based bearing alloy according to  claim 1 ,
 further containing at least one element selected from the group consisting of copper, zinc, and magnesium, a total amount of the selected element being not less than 0.1 mass % but not more than 7 mass %.