Desenvolvimento de rota tecnológica para produção de compósito de Nb-15%Cu utilizando moagem de alta energia e sinterização por SPS (spark sintering) visando aplicação em contatos elétricos

Abstract

Several materials are currently used for the production of electrical contacts, heat sinks and coils, with characteristics similar to those of the Nb and Cu composite studied in this work. In this way, the study and the development of a technological route for the production of a material of Nb and Cu for application in electrical contacts through high energy grinding with and without cryogeny and sintering through Spark Plasma Sintering ). For this, two powders of Nb and Cu, containing 15% by mass of Cu, were prepared and then milled by high energy grinding in a planetary type mill. The first powder was ground during the times of 1, 2 and 5 hours and the second was ground cryogenically for 26 hours. The analysis of the ground powders was obtained by SEM, EDS, XRD and IMAGE J. The samples of the powders ground for 1.2 and 5 hours were sintered in the liquid phase via SPS at temperatures of 1100, 1400 and 1600 ° C. The powders ground for 26 hours were sintered via SPS at temperatures of 1000 ° C and 1100 ° C. the sintered bodies were characterized and evaluated by CONFOCAL, SEM, EDS, DRX, EBSD, computed tomography, Vickers hardness, density and electrical conductivity. The bodies consolidated from the ground powders with the highest grinding time had higher values of density. Densified samples with up to 99.82% of the theoretical density were obtained for the sintered bodies of the crushed powders without cryogenics, and 97.8% for the sintered bodies of the compacted powders crushed with cryogen. The conductivity reached a maximum value of 1.78 x 107 mΩ, equivalent to 29.7 IACS. In relation to the hardness of the sintered, its maximum value reached was 473,84 HV.