Rk. Mahidhara, ON THE FORMATION OF NECKS IN AN AL-13-PERCENT-SI EUTECTIC ALLOY, Materials science & engineering. A, Structural materials: properties, microstructure and processing, 197(2), 1995, pp. 5-8
An Al-13%Si eutectic alloy was tested at an elevated temperature of 55
7 degrees C at constant strain rate. Marked deviations from uniform de
formation occurred in the specimens tested at three different strain r
ates of 1 x 10(-5), 5 x 10(-4) and 1 x 10(-2) s(-1) at elongations as
low as approximately 50%. At a strain rate of 1 x 10(-2) s(-1), a diff
use neck formed up to an elongation of 100%. Thereafter, the neck beca
me sharp and catastrophic. At strain rates of 5 x 10(-4) and 1 x 10(-5
) s(-1), failure occurred by the formation and subsequent growth of sh
arp necks within the gauge length. These results are consistent with a
genuine decrease in the value of the strain rate sensitivity index m
with a decrease in strain rate.