Accession Number : AD0763480

Title :   Low Temperature Solubility of Hydrogen in Niobium.

Descriptive Note : Technical rept.,

Corporate Author : ILLINOIS UNIV URBANA DEPT OF METALLURGY AND MINING ENGINEERING

Personal Author(s) : Holmquist,Gary R. ; Birnbaum,Howard K.

Report Date : JUL 1973

Pagination or Media Count : 31

Abstract : The precipitation of hydrogen from solid solution to form a hydride was studied in the Nb-H and Nb-D systems at temperatures between 77K and 300K. A large amount of undercooling was observed during cooling; the extent of which decreased after thermally cycling. On heating a large thermal hysteresis was observed before resolution of the hydrides occurred. These results were interpreted in terms of a precipitation model which requires a large amount of plastic accommodation to occur during precipitation. The effects of N additions and cold working were studied and shown to be consistent with this model. (Author)

Descriptors :   (*NIOBIUM, *HYDROGEN EMBRITTLEMENT), (*HYDROGEN, *SOLUBILITY), CHEMICAL PRECIPITATION, HYDRIDES, PHASE DIAGRAMS, ELECTRICAL RESISTANCE, LOW TEMPERATURE, DIFFUSION

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE