| To investigate the effect of cooling rate and Nb-content on the microstructure and corrosion characteristics of Zr-Nb alloys, four kinds of Zr-xNb(x = 0.5, 1.0, 2.0, 3.0 wt.%) alloys were designed and manufactured. The corrosion test and microstructural study were performed for the specimens which were heat-treated at 1020℃ for 30 minutes and then cooled by water quenching, oil quenching and air cooling. When the cooling rate was the same, the addition of Nb enhanced the change of microstructure from Widmansta¨tten to Martensite and decreased the corrosion resistance. In the equal Nb-content, the lath width and corrosion resistance increased with decreasing the cooling rate. It is considered that corrosion resistance would be related with the distribution of supersaturated Nb in Zr matrix. |
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