| Title |
Effects of Final Heat Treatment on Corrosion and Mechanical Properties of Zr Alloy Strip Incorporating Nb |
| Authors |
이명호(Myung Ho Lee); 정양일(Yang Il Jung); 최병권(Byoung Kwon Choi); 박상윤(Sang Yoon Park); 김현길(Hyun Gil Kim); 박정용(Jeong Yong Park); 정용환(Yong Hwan Jeong) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
Zirconium alloy; mechanical properties; corrosion; final annealing |
| Abstract |
The effects of final heat treatment on the mechanical and corrosion properties of a Zr alloy strip incorporating Nb were investigated. The chemical composition of the strip was Zr-1.49Nb-0.38Sn-0.20Fe-0.11Cr, and strip specimens were subjected to final heat treatment in a temperature range of 580~700℃. Tensile tests at room temperature and 316℃, along with corrosion tests in a simulated PWR loop and a 70 ppm LiOH solution environment at 360℃, were performed on the specimens. The mechanical properties of the strip were saturated when the specimens received final heat treatment at an elevated temperature of more than 640℃. However, the corrosion resistance of the strip in the simulated PWR loop and in the 70 ppm LiOH solution environment was improved with a decrease of the final annealing temperature. It is recommended that the alloy strip be finally heat-treated at a temperature of less than 620℃ for longer than 10 minutes in order to obtain fully recrystallized microstructures, and thereby attain enlarged tensile elongation, and to prevent the precipitation of β-Zr, which is known to deteriorate the corrosion resistance. |