Abstract
On the determination of hydrogen in ferroalloys, values obtained are much influenced by analytical methods and conditions of sample preparation. The authors have examined about the powdered sample and granular sample by using method of heating in argon carrier gas and fusion in argon carrier gas or vacuum, in order to establish a suitable method on the determination of typical hydrogen content.
The results obtained are as follows:
(1) In the granular sample of Fe-Ti, lower values are obtained by method of heating in argon carrier gas because of difficulty in extracting hydrogen from sample. On the other hand, in the powdered sample under through a 16 mesh sieve, hydrogen can be extracted completely.
(2) Hydrogen are not homogeneous in crushed sample of Fe-Mn, Fe-Si, etc. generally, hydrogen content in powder is much higher than that in granular and there are large differences in hydrogen content according to the positions (e. g. surface and core) of sample taken from the original block. Therefore it is desired to use powder sample mixed sufficiently after sampling homogeneously from crushed block in order to obtain a reliable values of hydrogen in ferroalloys.
(3) Absorption of hydrogen does not occur during crushing of block or granular sample and exposure of powdered sample in room atmosphere.
(4) Hydrogen values obtained by the fusion extraction method are much influenced by temperature of extraction at some kinds of alloys (e. g. Fe-V, Fe-Si). Therefore it is necessary to choose a suitable temperature according as composition.
