The mutual effects of boron, zirconium and aluminium on grain boundary segregation in Ni3Al intermetallic compounds
Journal
Materials Science and Engineering A
Journal Volume
141
Journal Issue
2
Pages
169-178
Date Issued
1991
Author(s)
Chuang, T.H.
Abstract
The fracture surface chemistries of Ni3Al intermetallic compounds with additions of boron and/or zirconium were analysed by Auger electron spectroscopy. The concentration variations of boron, zirconium and aluminium on grain boundaries and their influence on fracture behaviourwere evaluated. The results indicate that boron and zirconium segregated to grain boundaries, while the aluminium content decreased. The aluminium depletion is caused by the zirconium segregation rather than by the boron segregation. Boron segregation markedly improves the ductility, but zirconium additions do not seem to have the same beneficial effect. On the contrary, the increase in aluminium content in the non-boron-doped Ni3Al(Zr), results in a stronger tendency towards intergranular failure. © 1991.
Type
journal article
