The effects of boron impurities on the atomic bonding and electronic structure of Ni3Al

Tunable synchrotron radiation was used to examine the boron K-valence emiss ion from boron doped Ni3Al (500 parts per million boron). When compared wit h electronic structure calculations these measurements yield information re garding the local bonding environment of the doped boron atoms within the a lloy structure. Our measurements appear to suggest that the boron atoms pre ferentially bond with the nickel atoms in this material. It seems that the boron atoms prefer to occupy octahedral interstitial sites surrounded by si x nickel atoms. This suggests that the enhancement in ductility observed in this alloy is due to the interplanar metallic bonding provided by the dope d boron atoms. (C) 2000 Elsevier Science B.V. All rights reserved.