Abstract
The surface-treatment of cermet powder was investigated by means of X-ray photoelectron spectroscopy, X-ray diffraction method, scanning electron micrography, dispersive property measurement and pyrolysis. The influences of surface-treatment on the molding and the flow property of the blend with paraffin were also studied. The results obtained were summarized as follows: (1) The surface of cermet powder was recognized to be covered by an oxide layer which contains surface groups such as _??_TiOH, _??_COH, -COOH, _??_CO and _??_COC_??_; (2) When the cermet powder was surface-treated with alcohol, the nature of the surface changed from hydrophilic to hydrophobic; (3) From the analysis of pyrolysis products of surface-treated powder, the surface group was found to be the alkoxyl group of the alcohol used; (4) The apparent density of molded tabulet of surface-treated powder was higher than that of original powder, and the pore volume of the former was smaller than that of the latter; (5) The extrusion test of the blend with paraffin showed that the amount of paraffin needed for the surface-treated cermet powder was smaller than that for the original powder in order to obtain a similar property of flow.
