Abstract
In recent years, the sintered body of aluminum powder, which is very cheaper in price than tantalum, has been used as a dielectric material element; and a solid electrolytic condenser of sintered aluminum has been developed in industry.
Since 1965, the authors have studied on sintering mechanism of aluminum powder and the development of solid electrolytic condenser of sintered aluminum.
The sintering of aluminum for condensers had never been attempted, because aluminum has a considerably low melting point and easily be oxidized. Sauerwald (Germany) pointed out in 1922 that an oxide, which is hardly reduced by hydrogen, appears on the surface of aluminum powder so that its sintering is made impossible.
The authors considered that it would be possible to sinter the aluminum powder in vacuum and succeeded in its trial as expected. As the results of studies, the surface area of the sintered body was made larger to increase electric capacity.
The sintering mechanism of aluminum powder and characteristics of electrolytic condenser of sintered aluminum are discussed in this paper.
