Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Phase formation of Laves (Fe2Nb) under low temperature heat treatments after Mechanical Alloying
Submission Author:
Marcela Lamoglia , MG
Co-Authors:
Marcela Lamoglia, Marcos Gabriel Carvalho de Oliveira, Ágata Pontes, Pedro Henrique Gonçalves, Gilbert Silva
Presenter: Marcela Lamoglia
doi://10.26678/ABCM.COBEM2021.COB2021-1981
Abstract
Among the several chemical elements that are used on the formation of intermetallic precipitates, there is Niobium, which is responsible for increasing the mechanical strength of metallic alloys, through the precipitation of a second phase, as well as harden them with solid solution. Thus, materials with that element in its composition are of great interest on energy industries (steam turbines), chemical and oil industries, where materials with low density and high mechanical and corrosion resistance are relevant. For the Fe-Nb binary system, this work developed the composition Fe15Nb (at. %), through powder metallurgy using the Mechanical Alloying (MA) process. Currently, the phase diagram of the Fe-Nb system is not complete due to the inability of phase formation, by other techniques, with heat treatments at low temperature (below 1000 ° C), and the knowledge of its phase equilibrium is of great relevance for the microstructural understanding, helping on projections and providing data for thermodynamic modeling. In this work, methanol was used as Process Control Agent (PCA), to investigate its effect on the MA process, comparing with the results of the milling without adding PCA. The alloy was analyzed after 20, 40 and 60 hours of milling in high-energy planetary ball mill, in an inert atmosphere of argon gas, at 350 rpm. The morphologic analysis results indicate reduction in particle size when methanol is used. Subsequently, heat treatments at 600 °C, 800 °C and 1000 °C for 48 hours, to phase formation and/or stabilization. Through the X-ray diffraction technique, it was observed the formation of Laves phase (Fe2Nb) after heat treatment.
Keywords
Mechanical Alloying, Fe-Nb System, Laves, Process Control Agents, Powder metallurgy.
