The study of pressing mechanically activated niobium and silicon powder mixtures

Abstract

Abstract The paper presents the results obtained in the study of the pressing process of mechanically activated powder mixtures of the niobium – silicon system. Pressing often precedes the process of self-propagating high-temperature synthesis and the initial density of the compressed samples can have a significant impact on the regime of subsequent high-temperature combustion, on the composition and properties of the final product (niobium silicide). The obtained dependences of porosity on the time of mechanical activation showed the features of pressing, which are associated with the formation of layered agglomerates in the process of mechanical activation. It was found that the compression curves of mechanoactivated powders differ qualitatively from the standard compression curves of fine powders. The paper considers the influence of mechanical activation time on the density of the compressed samples obtained by varying the pressing pressure and the time spent under the press. The relationship between the density of compresses and layered agglomerates, which are formed during mechanical activation, is considered.