Abstract
This work deals with the oxidationbehaviour of apowdermetallurgy (PM) Ni3Al alloy synthesised using rapidly solidified powder particles, which were milled for 20 h before consolidation by hot isostatic pressing. Oxidation kinetics was evaluated in the temperature range of 535 to 1020°C, with special emphasis at 635°C for which tests were performed up to 1000 h. Oxidation rate was lower than that showed by the material made from non-milled powder particles, irrespective of the oxidation temperature and exposure time. This better oxidationbehaviour is associated to the smaller average grain size of the substrate induced during the milling stage, which favoured formation of a thin alumina layer | CICYT (Spain) for financial support under project MAT 95-796