Improved Properties of Lead-antimony Alloys by Thermomechanical Treatments.
Tilman-MM; Crosby-RL; Neumeier-LA
NTIS: PB 250 653 :26 pages
The federal Bureau of Mines developed a rolling method that improves creep resistance and yield strengths of lead alloys containing up to 5 wt-pct sb. The 0.69-Inch-thick slab-cast alloys were breakdown- rolled to 0.226 Inch and finish-rolled to 0.063 Inch at 5- or 20-pct reduction per pass. Rolling was at room temperature to simulate conventional cold rolling, and at 75 deg, 125 deg, and 175 deg c. Two alternative methods evaluated consisted of (1) a single cold final pass followed by annealing and (2) a single hot final pass. Two additional processing methods involving percipitation strenghthening were included for comparison. Compared with conventional cold rolling, hot rolling at 125 deg and 175 deg c with multiple light passes vastly improves creep resistance and raises yield strenths. Tensile strengths are less affected. The other treatments also improve creep resistance significantly and generally improve tensile properties; magnitudes vary with treatment and composition.
IH; Report of Investigation;
NTIS Accession No.
NTIS: PB 250 653