In:
Transactions of the Kоla Science Centre of RAS. Series: Engineering Sciences, Kola Science Centre, Vol. 2, No. 2/2023 ( 2023-04-10), p. 33-40
Abstract:
During long-term storage of wet fine zirconium metal powder under certain conditions the process of particles aggregation may start, which leads to powder transformation into a solid lumpy material, which significantly limits its application range. The purpose of this work was to establish the probable causes leading to the aggregation of zirconium powder particles during long-term storage, and to assess the possibility of transferring the lumpy material to its initial powdery state while preserving its basic physical and chemical properties. Particles aggregation most likely happens due to participation of zirconium atoms of the metal layers in formation of oxo-bridging bonds in acidic medium. Lumpy material formed in the process of storage of sodium-thermal zirconium metal powder (PZrN-A) was used as an example for testing the method of particles disaggregation by means of sodium hydroxide solution treatment, which makes it possible to transform the lumpy material into a stable powdery state typical for standard powder. The mechanism of alkaline treatment consists in the irreversible rupture of oxo-bridging bonds in the material, and the formation of hydroxyl groups on the surface of zirconium particles, which is accompanied by the destruction of aggregates and their disintegration into individual particles. Treatment with sodium hydroxide solution of different concentration demonstrates no significant changes in chemical composition of particles surface layers and makes it possible to maintain the main physical and chemical characteristics of zirconium powder. Samples of zirconium powder were studied by scanning electron microscopy, X-ray spectral microanalysis. The content of total and active zirconium, the value of the specific surface area of the powders was determined. Their sensitivity to friction and electric spark is evaluated.
Type of Medium:
Online Resource
ISSN:
2949-1215
Uniform Title:
ИЗУЧЕНИЕ ПРОЦЕССОВ АГРЕГИРОВАНИЯ И ДЕЗАГРЕГИРОВАНИЯ ЧАСТИЦ ВЫСОКОДИСПЕРСНОГО ПОРОШКА ЦИРКОНИЯ
DOI:
10.37614/2949-1215.2023.14.2
DOI:
10.37614/2949-1215.2023.14.2.005
Language:
Unknown
Publisher:
Kola Science Centre
Publication Date:
2023
