1989 Volume 53 Issue 1 Pages 149-155
Effects of serrated grain boundaries and cold work on the high-temperature creep-rupture properties of low-carbon cobalt-base superalloy L-605 are investigated at 1089 K and 1311 K.
Unlike other kinds of superalloys with high-carbon contents, serrated grain boundaries in L-605 alloy are formed by precipitation of tungsten-rich phase during a simple heat treatment. Rupture lives of specimens with serrated grain boundaries are larger than those of specimens with normal straight grain boundaries especially at 1311 K. The rupture ductility is also larger in specimens with serrated grain boundaries at 1311 K, but it is almost the same in both specimens at 1089 K.
A small amount of cold work up to 10% increases the creep resistance of both specimens at the expense of the creep ductility. The rupture lives are almost unchanged with a small amount of cold work.
