Copper-lead composite bearing material having fine lead size and method of producing same

摘要

An improved process and an improved composite bearing material produced thereby comprising a hard metal backing strip having leaded-bronze bearing lining tenaciously bonded to at least one face surface thereof and wherein the bearing lining is characterized by having the lead constituent thereof substantially uniformly distributed throughout the lining matrix in the form of extremely fine-sized particles providing improved operating characteristics to the bearing materials fabricated therefrom. In accordance with the process aspects of the present invention, the steel backing strip is provided with a metallic plating composed predominantly of nickel to at least the face on which a prealloyed leaded-bronze powder of a controlled composition is applied and is thereafter sintered at a controlled temperature for a short period of time sufficient to effect a liquid phase sintering of the powder together and the formation of a bond between the powder layer and the metallic plating on the face of the backing strip whereafter the sintered composite strip is cooled and is compacted usually at temperatures below about 300 DEG F. to effect a substantially complete densification of the powder layer. The composite strip is again reheated at a controlled temperature and for a brief period of time sufficient to further enhance the physical properties of the bearing lining and to further enhance the strength of the bond between the lining and backing strip under controlled conditions to inhibit growth of the fine-sized lead particles into undesirable larger particles. The composite strip is thereafter again cooled and may be subjected to a further compaction at moderate warm temperatures to achieve still further densification and to improve the physical properties and sizing of the composite strip.