The Effect of Boron on Microhardness in Ni3 Al Polycrystals


In a recent MRS symposium, the effect of boron on grain boundary hardness (GBH) in Ni3Al was reported. Addition of 0.2 at.% of boron decreased the GBH in all three sets of alloys tested (24, 25, and 26 at.% Al). The present paper summarizes the study of the effect of boron on hardness within grains. Boron-induced softening was again observed in grain interiors. However, it occurred only in alloys with 24 and 25 at.% Al, but not in the alloy with 26 at.% Al. An explanation for this behavior is presented.

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Qian, X.R., Chou, Y.T. The Effect of Boron on Microhardness in Ni3 Al Polycrystals. MRS Online Proceedings Library 133, 529 (1988).

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