Non-firing ceramics: Activation of silica powder surface by a planetary ball milling

• Published in: Advanced powder technology : the international journal of the Society of Powder Technology, Japan Japan, 2019-02, Vol.30 (2), p.461-465
• Main Authors: Nakashima, Yuki, Razavi-Khosroshahi, Hadi, Ishida, Hajime, Takai, Chika, Fuji, Masayoshi
• Format: Article
• Language: English
• Subjects: Ball milling; Pulverization; Silica (SiO2); Surface activation
• ISSN: 0921-8831; 1568-5527
• DOI: 10.1016/j.apt.2018.11.025

[Display omitted] •The silica powder can be activated at short time, 15 min by planetary ball mill.•The powders are pulverized and new active surfaces are formed at longer time.•The ratio of ball/powder is the important factor for the effective activation. “Non-firing” ceramics have recently attracted much attention in recent years because many functional materials can be achieved by this method without the aid of sintering process. Amorphous silica powder was mechanically treated by a planetary ball mill system, by which the surface of powders was activated and simultaneously particle size reduced extensively. Surface of powders with different milling conditions was investigated by scanning electron microscopy (SEM) and nitrogen adsorption isotherm. The surface activity of raw and treated silica powders was measured based on the water adsorbed volume on the powder surface. Results showed that the powder surface was activated, and the silica powders were pulverized as an effect of ball milling. At milling times as short as 15 min, the powder was rubbed against balls, and the friction between particle/ball breaks the bonds of functional groups like SiOSi on the surface of particles. For longer milling times, powders were pulverized and more new active surfaces were formed.