Accession Number : ADA017035

Title :   Hydrogen Embrittlement of Niobium. I - Macroscopic Behavior at Low Temperatures.

Descriptive Note : Technical rept.,

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

Personal Author(s) : Gahr,S. ; Grossbeck,M. L. ; Birnbaum,H. K.

Report Date : AUG 1975

Pagination or Media Count : 52

Abstract : The effect of hydrogen on the ductility of niobium was studied in the temperature range 77 to 300K. Tension testing and detailed fractographic studies were used to establish the roles of hydrogen concentration, temperature, yield stress and strain rate in the fracture process. It was shown that two ductility minima can be observed in the temperature range examined and that these are related to the precipitation of hydrides during the deformation process. The fracture mode is cleavage in the temperature range of both ductility minima. The solid solution of H in Nb was shown to be a highly ductile alloy; the ductility being terminated by the formation of a stress induced hydride which exhibits cleavage.

Descriptors :   *Niobium, *Hydrogen embrittlement, Low temperature, Cryogenics, Fracture(Mechanics), Hydrides

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE