Image Number 4 for United States Patent #4375499.
An aluminum-tin (Al-Sn) base bearing alloy and a bearing material which is made by applying the Al-Sn base bearing alloy to a backing steel sheet by pressure welding. The Al-Sn base bearing alloy of the invention is characterized in that the coarsening of tin particles and the lowering of the hardness under high temperature conditions are quite small so that the wear resistance as well as the fatigue strength of the alloy are quite excellent. The Al-Sn base bearing alloy comprises 3.5-35 wt. % of Sn; 1.2-10.0 wt. % of Cr; and the remainder of aluminum. The Al-Sn base bearing alloy of the invention can further contain 3 wt. % or less in total of Cu and/or Mg and 9 wt. % or less in total of one or more members of Pb, Bi and In, thereby improving the bearing characteristics. The wear resistance of this bearing alloy can be expected even when the shaft to be supported is hard and the shaft surface is coarse. Accordingly, a marked effect can be obtained when the bearing alloy is used for the bearing devices of internal combustion engines in which spheroidal (nodular) graphite cast iron is generally used for crank shafts.