| Title |
Microstrucrture Control of Zr-Nb-Sn Alloy with Mo Addition for HWR Pressure Tube Application |
| Authors |
김진홍(Jin Hong Kim) ; 황선근(Sun Keun Hwang) ; 김명호(Myoung Ho Kim) ; 권숙인(Sook In Kwon) ; 김영석(Young Suk Kim) |
| Abstract |
As a basic research to develop the material for heavy water reactor pressure tube application the effect of Mo addition to Zr-Nb-Sn alloy was studied for the purpose of minimizing the amount of cold working while maintaining a high strength. To select the target alloy system we first designed various alloy compositions and chose Zr-Nb-Sn and Zr-Nb-Sn-Mo through multi-regression analysis of the relationship between the basic properties and the compositions. Plasma arc melting was used to produce the alloys and the microstructure change introduced by the processing steps including hot forging, beta-heat treatment, hot rolling, cold rolling and recrystallization heat treatment was investigated. Recrystallization of Zr-Nb-Sn was retarded by adding Mo and this resulted in a fine grain structure in Zr-Nb-Sn-Mo alloy. Beside the retarding effect of recrystallization. Mo increased the amount of residual beta phase and showed an indication of precipitation hardening, which added up to the possibility of applying the alloy for the desired usage. |