UHPM - 95
J. Phys. IV France 05 (1995) C7-271-C7-275
Influence of Small Amounts of Boron on the Structural Evolution of Nanocrystalline Ni3Al During Thermal TreatmentsA. Korznikov1, 2, O. Dimitrov1, A. Quivy1, G. Korznikova2, J. Devaud1 and R. Valiev2
1 Centre d'Etudes de Chimie Métallurgique, CNRS, 94407 Vitry-sur-Seine, France
2 Institute for Metals Superplasticity Problems, Oufa, Russia
The influence of a boron addition (0.1 wt%) on the structural stability of high-purity nanocrystalline Ni3Al intermetallic compounds was investigated. The nanocrystalline structure was obtained by severe shear deformation under quasi-hydrostatic pressure. Residual electrical resistivity, Vickers microhardness, X-Ray diffraction and transmission electron microscopy were used to characterize the material evolution during thermal treatments in the temperature range 293-1313 K. After severe deformation the materials were disordered with a smaller crystallite size in the boron-doped compound than in the pure one. The boron addition was found to shift the long-range ordering, as well as the recovery of the properties investigated to higher temperatures, i.e. to improve the thermal stability of the structure.
© EDP Sciences 1995