Microscopic analysis of electroerozyon chrome-containing powders

Abstract

The method of electro-erosive dispersion (EED) is characterized by relatively low energy costs and ecological purity of the process and allows to obtain powders from wastes of production and consumption. Nevertheless, the wide use of the method of electro-erosive dispersion is hampered by the lack of reference material for optimizing the powder formation regimes and the properties of the obtained copper powders. For wide use of this method, extensive theoretical and experimental studies are required. The purpose of this work is to study their shape and condition of the surface of powders, obtained by electro-erosive dispersion of chromium-containing waste. By the method of scanning electron microscopy (SEM) on the Nova NanoSEM 450 device particles of powders, obtained by electro-erosive dispersion of chromium-containing waste, were investigated. It was found that the shape of the powder particles is due to the way, in which the material is ejected from the well in the EED process. It can be seen, that particles having a regular spherical or elliptical shape prevail in a powder. They are obtained by crystallization of molten material (liquid phase). The particles, formed during the crystallization of the boiling material (vapor phase), have an irregular shape, the size of an order of magnitude smaller, than the particles, formed from the liquid phase, and usually agglomerate with each other and on the surface of other particles. In the EES process, such particles are most susceptible to chemical and phase changes.

Keywords: Chrome-containing waste, electroerosive dispersion, powder, form, surface