Effect of plastic deformation on microstructure and properties of stir cast Al-Pb bearing alloy

A series of stir cast Al-Pb alloys with lead contents from 0 to 25 wt.% has been produced using a new foundry technique. Microstructures and mechanical properties of as cast and as rolled Al-Pb alloys have been investigated. 3D micrographs of the as rolled alloy containing 10 wt.%Pb indicates that the shape of lead particles changes from globule-like to dishlike. Both lead and silicon particles are refined significantly. As the content of lead increases, the mechanical properties (UTS and elongation) tend to decrease for both as cast and as rolled Al-Pb alloys. However, the values of UTS and percent elongation for as rolled Al-Pb alloys maintain higher than that for as cast Al-Pb alloys. The wear tests show that to minimise the friction and wear, an optimum amount of about 15 wt.%Pb is desirable in the studied Al-Pb alloy.