HARDENING IN BINARY LEAD-BARIUM AND TERNA RY LEAD-BARIUM-TIN ALLOYS

This work is devoted to the study of the age hardening process of bina ry Pb Ba and ternary Pb Pa Sn alloys in relation to the composition of the alloys and the phase diagram. A comparison with other systems Pb Ca, Pb Ca Sn, Pb Sr and Pb Sr Sn will be done, in order to understand the hardening mechanisms. To simulate the different processes of batte ry grid production, different initial states were systematically studi ed : as-cast product, rehomogenized, cold rolled or not. The alloys co ntain up to 1.75 wt % Ba and Sn. The times of aging were in the range from one minute to six months at room temperature. The limits of the s olubilities of Ba and Sn in Pb at different temperatures were estimate d by electron microprobe analysis.