32 nd International Field Emission Symposium / 32ème Symposium International d'Emission de Champ
J. Phys. Colloques 47 (1986) C2-209-C2-214
DOI: 10.1051/jphyscol:1986231
A TEM-APFIM INVESTIGATION OF BORON-DOPED Ni3Al
J.A. HORTON et M.K. MILLERMetals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, U.S.A.
Abstract
Boron additions to normally brittle Ni3Al result in room temperature ductilities over 50%. Little is presently known about the role of boron in strengthening the otherwise brittle grain boundaries. A TEM structural characterization of cast material shows a featureless microstructure while rapidly solidified material has substantial aluminum enrichments coupled with a bimodal APB distribution. Preliminary atom probe investigations of cast material found the boron in solution, with no evidence of clustering in the grain interiors. A small enrichment of boron was found at twin boundaries.