Effect of Fe Addition on Microstructure and Properties of Powder Metallurgy Ti35Nb10Ta Alloy

Abstract

[EN] The high contents of noble refractory elements of Ti35Nb10Ta (wt.%) alloy difficult the diffusion of them. The stabilization of the ß phase can be favored by the addition of Fe in ß-Ti alloys. In this work, elemental powders mixture with different contents of Fe (0, 1.5, 3.0 and 4.5 wt.%) were used. These powders were compacted with uniaxial pressure of 600MPa and sintered at 1250°C in high vacuum. The porosity obtained after sintering shows a dependence on the particle size of iron used, and homogeneous pores distribution was observed. The analyzed microstructure mainly corresponds to ß-Ti phase, with small fractions of ¿ phase appearing at grain boundaries, which decreases with increasing of Fe content. The microstructure showed good compositional homogeneity of Fe and Ta and some lack of diffusion related to large amount of undissolved Nb particles. Addition of Fe lead to a decrease in bending strength of Ti35Nb10Ta alloy.