Published online by Cambridge University Press: 26 February 2011
The effect of 0.2 at.% boron on grain boundary hardness in Ni3Al containing 24 to 26 at.% Al was studied. Normal grain boundary hardening was observed in all alloys with and without boron. However, the addition of boron decreases the magnitude of the grain boundary hardness, and the degree of “softening” depends on alloy stoichiometry. The occurrence of boron-induced softening is likely due to the increase in mobility of grain boundary dislocations.