Fatigue Characteristics of Laser Welded Zirconium Alloy Thin Sheet

doi:2012.30.1.59

J Weld Join > Volume 30(1); 2012 > Article

Research Paper

Journal of KWJS 2012;30(1):59-63.
DOI: https://doi.org/10.5781/KWJS.2012.30.1.59 Published online October 11, 2012.

레이저 용접된 박판 지르코늄 합금의 피로특성

Fatigue Characteristics of Laser Welded Zirconium Alloy Thin Sheet

Abstract

The spacer grid is one of the main structural components in a fuel assembly. It supports fuel rods, guides cooling water and maintains geometry from external impact load and cyclic stress by the vibration of nuclear fuel rod, it is necessary to have sufficient strength against dynamic external load and fatigue strength. In this study, the mechanical properties and fatigue characteristics of laser beam welded zircaloy thin sheet are examined. The material used in this study is a zirconium alloy with 0.66 mm of thickness. The fatigue strength under cyclic load was evaluated at stress ratio R=0.1. S-N curves are presented with statistical testing method recommend by JSME- S002 and compared with S-N curves at R.T. and 315℃. As a result of the experimental approach, the design guide of fatigue strength is proposed and the results obtained from this study are expected to be useful data for spacer gird design.

Key Words: Spacer grid, Zirconium alloy, Laser beam weld, Mechanical property, Fatigue characteristics, Vickers hardness