Caracterização estrutural e avaliação da resistência à oxidação de ligas Ti-Fe-Si-B produzidas por moagem de alta energia e subsequente tratamento térmico

Abstract

This proposal aims at structural characterization and evaluation of the oxidation resistance of Ti-Fe-Si-B produced by high energy ball milling and subsequent heat treatment. In this study, quaternary alloys were prepared from raw materials of high purity: Ti (99.9% by weight) Fe (99.8% by weight), Si (99.999% by weight) and B (99.5 % by weight). In step grinding of the powders obtained alloys Ti-2Fe-11B-22Si and 7Fe-Ti-22Si-11B (at-%) were produced by using a planetary ball mill of high energy. Subsequently, the Ti-Fe-Si-B were sintered and heat treated (1100 ° C for 4 hours) in vacuum to obtain equilibrium structures. The characterization of the milled and annealed alloys was performed with the aid of techniques X-ray diffraction, optical microscopy, scanning electron microscopia, Vickers hardness and thermal analysis. It is important to mention that information relating to studies of phase stability in alloys based on the system Ti-Si-B are limited in the literature. Thus, the present study aims to evaluate the oxidation resistance of Ti-Fe-Si-B with high levels of Titanium.