Surface characterisation and modification of submicron and nanosized silicon carbide powders

✍ Scribed by S. Novak; J. Kovač; G. Dražić; J.M.F. Ferreira; S. Quaresma

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 999 KB
• Volume: 27
• Category: Article
• ISSN: 0955-2219
• DOI: 10.1016/j.jeurceramsoc.2007.02.199

✦ Synopsis

The surface characteristics of two grades of silicon carbide powders were analyzed and modified with the aim to control and tailor their behaviour in colloidal suspensions. The as-received submicron and nanosized SiC particles were both found to be covered with a thin oxygen-containing layer, composed mostly of SiO 2 and SiC x O y ; however, their electrokinetic behaviours in aqueous suspensions were observed to be different. We coated the powders with a thin layer of aluminium oxy-hydroxide, which was found to modify their electrokinetic behaviours in aqueous suspensions. The composition and structure of the aluminium-containing layer were characterized by X-ray photoelectron spectroscopy (XPS) and TEM analyses. This coating may subsequently serve as a homogeneously distributed source of a low amount of sintering additive in manufacturing the SiC-based material for fusion application.