Numerical simulation using in the preparation process of micron‐sized silica–aluminium composite powders by high‐energy alloying: Building visualisation and guiding preparation

• Published in: Micro & nano letters 2023-05, Vol.18 (5), p.n/a
• Main Authors: Guo, Zhen‐yu, Zhang, Xin, Wang, Yan‐jun, Zhang, Si‐yuan, Yin, Yin
• Format: Article
• Language: English
• Subjects: Alloy powders; Aluminum; Ball milling; Boundary conditions; Discrete element method; Energy; Energy transfer; Experiments; Flame spraying; Friction; Impact analysis; mechanical alloying; Mindlin plates; Modelling; Particle size distribution; Powder spraying; powders; Pressure distribution; Process parameters; scanning electron microscopes; Silicon; Silicon dioxide; Simulation; surface recombination; Three dimensional composites; wear resistant coatings
• ISSN: 1750-0443; 1750-0443
• DOI: 10.1049/mna2.12165

Silica‐aluminium composite powders are important precursors for the preparation of sealant coatings by supersonic flame spraying. Micron‐scale silica‐aluminium composite powders can be prepared using a planetary ball mill, but powder agglomeration often leads to composite failure. Using relevant modelling software to build the 3D modelling of the ball mill jar, which based on the discrete element method, using the Hertz–Mindlin contact model and after specifying the simulation boundary conditions, the ball mill process was simulated and analysed. Visualise the influence of important process parameters such as frequency, size and diameter of milling balls and ball‐to‐powder weight ratio, and systematically analyse the microscopic morphology and composite condition of the agglomerated and dispersed powders. The results show that the ball motion during the ball milling process is mainly divided into three representative types: ball–ball impact, ball crushing motion against the jar wall and ball–wall impact. The energy transfer efficiency of the milling balls to the powder system is highest when the ratio of the three types of motion is uniform. SEM images and EDS spectra showed that the aluminium powder was sufficiently crushed, with an average particle size below 1 μm. The aluminium powder was uniformly distributed on the surface of the silicon powder, and the particle size of the composite silicon aggregates was sufficiently reduced. Different morphologies of In2O3 nanostructures had been synthesised via hydrothermal combined with calcination.• The FE behaviours of In2O3 nanostructures were investigated.• The field emission properties of the In2O3 nanorod‐flowers were enhanced greatly due to the higher length to diameter ratios of the emitting tips and the better crystal quality.