Specific surface determination e.g. of metal powders - in radioactively labelled gas contg. getter to eliminate other gases

摘要

Appts. for determining the specific surface of a powder operates by gas adsorption and the recording of the adsorption isotherm for an inert, radioactively labelled gas by the specimen. The space contg. the measuring gas and the specimen also contains a getter, which can be regenerated before and after the recording, to keep other, foreign gases out of of the space. More specifically, the getter is a band or wire of a material which combines O and N. In partic. Ta at is approx. 1600 degrees C., esp. obtd. by direct electric resistance heating, is used. Used partic. for determining the specific surface of metal powders and metal oxide powders. The arrangement enables improved accuracy to be achieved, partic. for measuring specific surfaces of 0.3 m.3 g. and enables the error due to extraneous gases within the atmos. surrounding the specimen to be kept 5%.