Original Article

Effects of powder feeding rate on porosity and tensile strength of powder feeding laser welded Al-30wt.% B₄C composite with the addition of Al powder

Institute of Materials, China Academy of Engineering Physics, Mianyang 621908, China

^* e-mail: lyjcaep@163.com
^** e-mail: 13981102769@163.com

Received: 29 December 2022
Accepted: 11 March 2023

Abstract

Al-B₄C metal matrix composite is an advanced neutron absorption material. In order to obtain a wider application in spent nuclear fuel storage and transport, the welding technique is essential for Al-B₄C composites. In this paper, powder feeding laser welding (PFLW) method was used to weld Al-30wt.% B₄C composite. During the experiments, Al powder was used as the filler metal, the effects of powder feeding rate on porosity, neutron shielding ratio and tensile strength of the joints were investigated by using micro-CT (micro computed tomography), OM, SEM and TEM. It is found that PFLW has a significant weld porosity suppression effect, and a joint efficiency (UTS) of 87% is obtained in PFLW of Al-30wt.% B₄C composite with the powder feeding rate of 1.2 g/min. The neutron shielding ratio of the joint reduced by 3% due to the volume ratio of AlB₁₂C₂ (a B-rich reaction product) reduced by 7.6% when the powder feeding rate is 1.2 g/min. The results illustrate the great potential of PFLW in welding Al-B₄C composites.