Deformed microstructures of two-phase Zr–2.5Nb alloy: Effects of the second phase hardness

• Published in: Journal of nuclear materials Vol. 404; no. 3; pp. 222 - 230
• Main Authors: Sahoo, S.K., Hiwarkar, V.D., Jain, L., Samajdar, I., Pant, P., Dey, G.K., Srivastav, D., Tewari, R., Banerjee, S.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 30-09-2010; Elsevier
• Subjects: Applied sciences; Controled nuclear fusion plants; Energy; Energy. Thermal use of fuels; Exact sciences and technology; Fission nuclear power plants; Fuels; Installations for energy generation and conversion: thermal and electrical energy; Nuclear fuels; Grain size; Zirconium alloy; Microstructure; Grain boundary; Nuclear reactor
• ISSN: 0022-3115; 1873-4820
• DOI: 10.1016/j.jnucmat.2010.07.028

Two types, A and B, of Zr–2.5Nb samples were subjected to compression tests. Both samples consisted of similar microstructure – hexagonal closed packed (hcp) α phase (the primary phase) and grain boundary bcc (body centered cubic) β phase. However, the hardness of the β phase differed between the samples – respectively being hard (sample A) and soft (sample B) relative to the primary phase. This difference was caused by the presence of fine ω precipitates. The relative hardness of β phase determined almost all aspects of deformed microstructure developments. In sample A, the primary phase had higher lattice strain and in-grain misorientation developments. In sample B, on the other hand, the softer β phase was clearly linked to more deformation twinning and associated grain size refinement and ‘texturing’ of the hcp α phase.