Details

Autor(en) / Beteiligte

• Zan, YuNing
• Wang, BeiBei
• Zhou, YangTao
• Jia, CunLei
• Liu, ZhenYu
• Wang, QuanZhao
• Xiao, BoLv
• Ma, ZongYi

Titel

Microstructure and mechanical property evolution of friction stir welded (B4C+Al2O3)/Al composites designed for neutron absorbing materials

Ist Teil von

• Science China. Technological sciences, 2020-07, Vol.63 (7), p.1256-1264

Ort / Verlag

Beijing: Science China Press

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• (B 4 C+Al 2 O 3 )/Al composite designed for the dry storage of spent nuclear fuels was fabricated and then subjected to friction stir welding, at a welding speed of 100 mm/min and rotation rates of 400–800 r/min. Sound joints were obtained under all welding parameters; however, significant softening occurred in the nugget zone (NZ) for all the joints. Therefore, all the joints exhibited significantly decreased strength at both room temperature and high temperature compared with the base metal, with the joints fracturing in the NZs. Rotation rate exhibited no obvious effect on the tensile strength of the joints, but led to increased elongation as the result of the broadened NZs. The detailed microstructural examinations indicated that the welding thermo-mechanical effect broke up the near 3D amorphous Al 2 O 3 netlike structure distributed at the Al grain boundaries, caused the coarsening of Al grains, and the agglomeration and crystallization of amorphous Al 2 O 3 , thereby resulting in the softening of the NZs and the reduction in the joint strength. Consequently, inhibiting the breakup and crystallization of 3D amorphous Al 2 O 3 netlike structure is the key factor to improve the joint strength of the (B 4 C+Al 2 O 3 )/Al composite.