Phase Diagram of the Niobium-Tin System
Abstract
The phase diagram of the high tin portion of the niobium-tin system was constructed. The temperature range of stability of the various intermetallic compounds was determined. Ten alloys were arc melted, cast, and annealed at 750 degrees centigrade for 700 hr. On the basis of x-ray, thermal and microstructural analysis, a phase diagram was constructed. Differential thermal curves are given, and the various temperature peaks are analyzed. Besides Nb3Sn, two other intermetallic compounds, Nb6Sn5 and NbSn2 exist in the niobium-tin system. However, they only form upon protracted annealing. For case niobium-tin alloys, in which the compounds Nb6 and NbSn2 are absent but in which the above monotectic occurs, a metastable equilibrium diagram can be constructed. In the metastable diagram, the equilibrium monotectic temperature and composition may differ from that obtained for a stable diagram. Apparently, the niobium-tin diagram obtained by Agafonov, et al is a metastable one.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 07, 1969
- Accession Number
- AD0700589
Entities
People
- V. M. Pan
- V. N. Svechnikov
- Yu. I. Beletskii
Organizations
- Air Force Systems Command