The Effect of Heat Treatment on Mechanical and Corrosion Performances of Zr-Nb Alloy

摘要

The mechanical performance and corrosion resistance of Zr-Nb alloy (Zr705) treated in different ways is tested, and it is found that those properties of Zr-Nb alloy are significantly affected by heat treatment. The most important parameter of the heat treatment is quenching temperature. The Zr-Nb alloy, quenched below the critical quenching temperature Tcq (a temperature or a range of temperature between 850°C-870°C） presents good corrosion resistance performance, however, quenched above the Tcq gets a higher strength and a lower corrosion resistance. Through the study on the basis of the evidences gotten by means of metallographic, SEM, EPMA and TEM, the conclusion can be drawn as that the effect of heat treatment on the performances of Zr-Nb alloy is primarily because of the mechanism of the distribution change of Nb, the quantity of β-Zr, the morphology of grains.