Bearing material and solid lubricant

A bearing element, comprising

• a substrate;
• an overlay layer on the substrate;
• and
• an intermediate layer between the substrate and the overlay layer,
• the overlay layer including:
• a matrix of polyamide-imide polymer material;
• a solid lubricant particulate, in an amount of between about 5 wt. % and about 15 wt. % based on 100 wt. % total of the overlay layer;
• and
• a metallic particulate comprising metal flakes having a length of less than 10 μm in a longest dimension and less than 1 μm in a dimension perpendicular to the longest dimension, in an amount of between about 15 wt. % and about 35 wt. % based on 100 wt. % total of the overlay layer;
• wherein the metal flakes comprise at least one of aluminum, aluminum alloys, copper, copper alloys, silver, tungsten, tin, and stainless steel;
• wherein the solid lubricant particulate comprises at least one of molybdenum disulphide, tungsten disulphide, hexagonal boron nitride, and metal sulphides with layered structures;
• wherein the solid lubricant particulate has a median particle size of between about 100 nanometers and about 800 nanometers;
• wherein the solid lubricant particulate and the metallic particulate are distributed substantially homogeneously throughout the matrix of polyamide-imide polymer material;
• the intermediate layer comprises at least one of a copper-based material and an aluminum-based material,
• wherein the intermediate layer has a thickness of from 0.1 millimeters to 0.5 millimeters;
• and
• the overlay layer has a thickness of between 3 micrometers and 18 micrometers.