High-energy ball milling of nonstoichiometric compounds

Abstract

The preparation of nanocrystalline powders of nonstoichiometric compounds such as carbides and oxides by high-energy milling is considered. The modern state of milling models for nonstoichiometric compounds is described. The influence of nonstoichiometry on the particle size of the produced nanopowders is discussed. The model dependences of the size of nanopowder particles on the duration of milling and the composition of nonstoichiometric compounds are compared with the literature experimental results on the milling of nonstoichiometric carbides and oxides. Diffraction methods for the certification of nanopowders according to the size of the nanoparticles, the magnitude of microstrains, and the uniformity of the microstructure are considered in detail. The importance of taking into account the anisotropy of microstrains in milled nanopowders is shown.

A Review of Top‐Down Strategies for the Production of Quantum‐Sized Materials

“…[171] Ball-milling technology has significant advantages in preparing various downsized metals/alloys, oxides, carbides, and inorganic/organic compounds or mixtures. [172,173] In the field of nanotechnology, ball-milling was applied for the fabrication of various nanomaterials such as carbon-based nanomaterials, ceramic nanomaterials, and nanoalloy materials. To obtain extremely downsized nanomaterials, most efforts were committed to changing the parameters of ball-milling, including increasing ball-milling speed, extending ball-milling time, and adjusting feed ratio.…”

Effect of Stoichiometry and Ordering on the Microstructure of Titanium Monoxide TiOy

“…It possesses a wide homogeneity region (0.8 > y > 1.3) and contains up to 16 at. % structural vacancies in both titanium and oxygen sublattices simultaneously. − Such considerable amount of vacancies results in significant differences in the properties of substoichiometric, stoichiometric, and superstoichiometric TiO y in both ordered and disordered states. − In addition, a size effect was detected in the properties of nonstoichiometric titanium monoxide nanocrystals. − Earlier in ref , mechanical and annealing twins, longitudinal and transverse cleavage steps due to intermittent motion of twin boundaries had been found in nonstoichiometric titanium monoxide. When the stoichiometry changed, the curvature of cleavage edges because of the effect of defects (vacancies) and elastic stress inhomogeneity was observed.…”