Dry bearings(bronze/black PTFE), made of tin bronze as base material, are produced by the process of being sintered bronze powder as medium layer and coated PTFE as lubrication layer. They are in conformity with the European RoHS environmental protection standards and widely used in the applications of automotive, bicycle, hydraulic transmission, metallurgy and casting due to the advantages of lead free, low friction coefficient, good self-lubricating, good wear resistance and good thermal conductivity.