Microstructural evolution of Ti-10Nb and Ti-15Nb alloys produced by the blended elemental technique Martins, G.V. 1, a , Silva, C.R.M. 2, b , Henriques, V.A.R. 3, c ,Borges Junior, L.A. 4, d , Souza, J.V.C. 1,e , Machado, J.P.B. 1, f 1 INPE, Av. dos Astronautas, 1.758, S. J. Campos - SP, CEP. 12245-970, Brazil 2 UnB, Asa Norte, Brasília - DF, CEP. 70910-900, Brazil 3 DCTA-IAE/AMR - Pça. Mar. do Ar E. Gomes, 50, S. J. C. - SP, CEP. 12228-904, Brazil 4 UNIFOA, Av. Paulo E. A. Abrantes, 1.325, Volta Redonda – RJ, CEP. 27240-560,Brazil a givmartins@yahoo.com.br, b cosmeroberto@gmail.com, c vinicius@iae.cta.br, d borges.jr@itelefonica.com.br, e vitor@las.inpe.br, f joaopaulo@las.inpe.br Keywords: Ti-Nb alloy, powder metallurgy, microstructure and mechanical properties. Abstract. Alfa/beta titanium alloys have been intensely used for aerospace and biomedical applications. Production of powder metallurgy titanium alloys components may lead to a reduction in the cost of parts, compared to those produced by conventional cast and wrought (ingot metallurgy) processes, because additional working operations (machining, turning, milling, etc.) and material waste can be avoided. In this work, samples of Ti- 10, 15Nb (weight%) alloys were obtained by the blended elemental technique using hydride-dehydride (HDH) powders as raw material, followed by uniaxial and cold isostatic pressing with subsequent densification by sintering carried out in the range 900–1500 ºC. These alloys were characterized by X-ray diffractometry for phase composition, scanning electron microscopy for microstructure, Vickers indentation for hardness, Archimedes method for specific mass and resonance ultrasound device for elastic modulus. For the samples sintered at 1500ºC it was identified α and β phases. It was observed the influence of the sintering temperatures on the final microstructure. With increasing sintering temperature, microstructure homogenization of the alloy takes place and at 1500 ºC this process is complete. The same behavior is observed for densification. Comparing to the Ti6Al4V alloy properties, these alloys hardness (sintered at 1500 ºC) are near and elastic modulus are 18% less. Introduction Titanium and its alloys have over the years proven themselves to be technically superior and cost effective materials for a wide range of applications spanning the industries of aerospace, biomedical, marine, and even commercial products [1]. This is because of their high strength to weight ratio, stiffness, immune to corrosion in sea water environment, good erosion resistance, and importantly their acceptable mechanical properties at elevated temperatures [2]. Cost reductions can be obtained by vacuum hot pressing (VHP) and powder metallurgy (P/M) techniques by producing near net shapes and consequently minimizing material waste and machining time [3]. Some titanium alloys present a very low modulus of elasticity which is roughly half that of steel and nickel alloys. Materials with high flexibility (i.e. low elastic modulus) present reduced bending and cyclic stresses in deflection-controlled applications, making it ideal for Seventh International Latin American Conference on Powder Technology, November 08-10, Atibaia, SP, Brazil 170