Elucidation of mechanism and development of control method for re-aggregation phenomenon during wet ball milling of ceramics particles

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K22457
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0401:Materials engineering, chemical engineering, and related fields
• Research Institution: Tohoku University
• Principal Investigator: Kushimoto Kizuku 東北大学, 多元物質科学研究所, 助教 (10846439)
• Project Period (FY): 2020-09-11 – 2022-03-31
• Keywords: 粉体シミュレーション / 湿式ボールミル / DEM－CFD / 再凝集

Outline of Final Research Achievements

We elucidated the mechanism for the re-aggregation phenomenon observed during wet ball milling of ceramics particles and developed the control method for the phenomenon. The re-aggregation phenomenon has difficulty in being analyzed by experiments because the phenomenon is observed during wet ball milling and occurs in the scale of particles. Thus, first of all, the simulation method for analyzing the re-aggregation phenomenon was developed. From using the simulation, we analyzed the re-aggregation mechanism and found that the re-aggregation being collected in stagnated fluid flow that occurred when the grinding balls were approaching and separating each other. Furthermore, it was suggested that the re-aggregation could be suppressed by increasing the relative velocity of the grinding balls when approaching and separating each other in order to decrease the stagnation area of the fluid flow.

Free Research Field

粉体シミュレーション

Academic Significance and Societal Importance of the Research Achievements

本研究は、これまでそのメカニズムが明らかとされてこなかった湿式ボールミル内で生じる再凝集に対し、独自に開発したシミュレーション手法を解析ツールとして応用することでその発現メカニズムを明らかにした点で学術的な意義がある。
また、ナノ粒子の量産化の実現には、湿式ボールミルのような粉砕によるナノ粒子製造の実現が必要不可欠であるが、これまでは再凝集現象の抑制が困難であるため、その量産化も難しいとされてきた。本研究では、その再凝集のメカニズムだけでなく抑制方法も明らかにできたことから、ナノ粒子の量産化を実現する上で重要な知見を得た点で社会的意義がある。