Computational Prediction of Stability of Alumina Nanoparticles Dispersed in Aqueous Medium Using Discerete Element Method

It is known that stability of ceramic suspensions during forming process can influence strength and porosity content of final products. Theoretical methods are suitable for studying stability of nanoparticles in the suspension. In these methods, the contact between particles and formation ofagglomerates, which has an important role in stability of suspension, can be predicted. In thepresent paper, the behavior of nanoparticles dispersed in liquid medium is investigated withdiscrete element method. In this numerical method, first, forces such as Brownian, Buoyancy, friction, cohesion, contact, van der Waals attraction and electrostatic repulsion acting on each particle are calculated. Next, particle trajectory is determined with integrating from equation ofmotion of particle. The effect of process parameters such as pH and concentration on stability of asuspension containing nano-Alumina powder dispersed in an aqueous medium is investigatedtheoretically and experimentally. Experimental results confirm the results obtained from mathematical model developed in this work.

Keywords:

Contact Mechanics , Discrete Element Method (DEM) , JKR Theory , DLVO theoty , Alumina Nanoparticle , Stability