Accession Number : AD0632071

Title :   STRUCTURAL DIAGRAM OF NIOBIUM-NICKEL SYSTEM,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Svechnikov,V. N. ; Pan,V. M. ; Korobeinikova,V. G.

Report Date : 30 MAR 1966

Pagination or Media Count : 18

Abstract : A complete diagram of phase equilibriums of a niobium-nickel system was formulated. It was found that from the side of nickel rich alloys, the variant of the diagram, introduced by S. A. Pogodin and A. N. Zelikman, is confirmed. It was shown that in alloys of Nb-Ni system, four phases exist in solid phase: the alpha-solid solution of nickel and niobium (maximum solubility of about 4.5%, solubility at 1100C - 1.2% and at 800C - 0.6% Ni), alphasolid solution of niobium in nickel (maximum solubility about 13.5%, solubility of 1100C - about 12% Nb (delta-phase intermetallide Ni3Nb with a melting point of 1430C and a very narrow (less than 1%) area of homogeneity and eta phase - intermetallide NiNb with a wide area of homogeneity (6.4% at 800; 8.4% at 1000 and 12.8% Xat 1170C). It was established that phases existing in the alloys of the system form with liquid three triphase nonvariant equilibriums. Nickel additions, raising the hardness of niobium, do not improve the preservation of hardness at high temperature (800 - 1000C). Small (up to 4 weight %) additions of nickel considerably increase the hardness resistance of niobium (bi - 5-fold) when testing in air for a period of 5 hours at 1000C. (Author)

Descriptors :   (*NIOBIUM ALLOYS, *NICKEL ALLOYS), USSR, HARDNESS, MICROSTRUCTURE, EUTECTICS, SOLID SOLUTIONS, PHASE STUDIES

Subject Categories : Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE