A BIMETALLIC STRIP FOR A SLIDING BEARING AND PROCESS FOR PRODUCING SAID BIMETALLIC STRIP.

摘要

A bimetallic strip for a sliding bearing and process for producing said bimetallic strip, the latter being of the type comprising a sliding strip (1), which is made of aluminium alloy and which is adhered to a supporting strip (2), which is usually made of steel and which is optionally coated with a nickel coating interlayer (3). The process comprises the following steps) a- casting by the quick solidification process (roll cast) an alloy comprising from 3 to 30 percent of tin, from 1 to 6 percent of silicon and the remaining being of aluminium and accidental impurities, by pouring the cast alloy between two cold rolling cylinders, in order to obtain at least 95 percent of the silicon particles smaller than 3.5 microns and an aluminum grain average size of about 6 microns; b) annealing the aluminium alloy sliding strip (1) in a heater at a temperature range from 200 to 500 degree C; c) setting, optionally, the thickness of the sliding strip (1), through cold rolling passes, followed by respective annealings, as defined in the previous step; d) hot rolling (cladding) together the sliding strip (1) and the steel supporting strip (2), in order to form the bimetallic strip; e) heat treating the bimetallic strip between 200 and 380 degree C, so as to obtain a metallurgical bonding between the strips; f) subjecting the metallic strip to a solubilizing process of the intermetallic compounds of the aluminum alloy, by sudden heating at 380-500 degree C, followed by sudden cooling; and g) subjecting the bimetallic strip to an artificial precipitation treatment in a heater, at a temperture from 150 to 250 degree C.