Grain-boundary migration in Zr-Sn alloys

• Published in: Journal of nuclear materials 1979-12, Vol.87 (2), p.297-302
• Main Authors: Snowden, K.U., Stathers, P.A., Hughes, D.S.
• Format: Article
• Language: English
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/0022-3115(79)90566-X

Measurements are reported of grain-boundary migration in a series of Zr-Sn alloys containing from 0.75 to 5.1 wt% Sn (0.58 to 4.0 at% Sn) fatigued under vacuum at temperatures between 600 and 775°C. At these temperatures, the condition of the alloys correspond to either the single phase (α) or the double phase (α + Zr 4Sn) regions of the phase diagram. The amount and rate of grain-boundary migration increased with temperature and decreased with tin addition. The dependence of grain-boundary migration on tin content was a minimum at tin compositions which corresponded to the reported region of the α/(α + Zr 4Sn) boundary. In the α-region, the reciprocal of the rate of grain-boundary migration was approximately linear with tin content. The temperature dependence for grain-boundary migration exhibited a kinetic transition temperature which divided the dependence into two ranges characterised by different apparent activation energies. The effect of tin additions on both activation energies was to first reduce and then to increase their value. This latter increase is possibly associated with the precipitation of Zr 4Sn at grain boundaries.