Authors: B B Straumal A S Gornakova Y O Kucheev B Baretzky A N Nekrasov
Publish Date: 2012/02/11
Volume: 21, Issue: 5, Pages: 721-724
Abstract
ZrNb alloys play the important role in the energy production being the main material for the cladding of nuclear fuel in the nuclear power plants The thermomechanical treatment of these alloys proceeds in the αZr + βZr Nb twophase area of the ZrNb phase diagram Therefore the morphology and the mutual arrangement of the Zr and Nb phases play an extremely important role The microstructure of binary ZrNb alloys with 25 4 and 8 wt Nb after long anneals 720 h was studied between 660 and 810 °C in the twophase αZr + βZr Nb area of the ZrNb phase diagram βZr Nb/βZr Nb grain boundaries GBs completely or incompletely wetted by the αZr phase were observed The portion of the completely wetted βZr Nb/βZr Nb GBs increases from 10 at 660 °C to 60 close to the upper border of the αZr + βZr Nb twophase area of the ZrNb phase diagram 850 °C The temperature of the beginning of the GB wetting phase transition of βZr Nb/βZr Nb GBs by the αZr phase is T ws = 630 ± 10 °C The αZr/αZr GBs completely wetted by a layer of βZr Nb phase were not observed in the studied samplesThis article is an invited submission to JMEP selected from presentations at the Symposia “Wetting soldering and brazing” and “Diffusion bonding and characterization” belonging to the Topic “Joining” at the European Congress and Exhibition on Advanced Materials and Processes EUROMAT 2011 held September 1215 2011 in Montpellier France and has been expanded from the original presentation
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