Highly wear-resistant overlay with improved slip and a method of its production

A method of making and operating a plain bearing, comprising the steps of:

• forming on a carrier a base layer of a binary or ternary alloy of at least two different elements one of which is selected from the group which consists of copper, lead, tin, antimony, indium and thallium and another of which is a pure soft metal selected from the group which consists of tin, antimony, and mixtures thereof, the base layer having a surface against which a member can slide;
• applying to said layer the pure soft metal;
• heating said layer to diffuse said soft metal partly into said layer so that said layer has a concentration of said soft metal at said surface corresponding to a maximum concentration of the soft metal diffused into said layer from the pure state of the soft metal, said soft metal having a concentration in said layer decreasing in a diffusion gradient from said surface in a direction perpendicular to said surface and equal at a minimum to the concentration of the soft metal in the layer prior to application of the soft metal to the layer;
• thereafter frictionally engaging said surface with said member to effect bearing wear of said layer along a wear front into the thickness of said layer and progressive thermal diffusion by friction heat of said soft metal progressively more deeply into said layer ahead of said wear front.

A bearing made by the process comprising the steps of:

• forming on a carrier a base layer of a binary or ternary alloys of at least two different elements one of which is selected from the group which consists of copper, lead, tin, antimony, indium and thallium and another of which is a pure soft metal selected from the group which consists of tin, antimony, and mixtures, thereof, the base layer having a surface against which a member can slide;
• applying to said layer the pure soft metal;
• and
• heating said layer to diffuse said soft metal partly into said layer so that said layer has a concentration of said soft metal at said surface corresponding a pure state of the soft metal, said soft metal having a concentration in said layer decreasing in a diffusion gradient from said surface in a direction perpendicular to said surface and equal at a minimum to the concentration of the soft metal in the layer prior to application of the soft metal to the layer.