On March 13, 2023, Guangtao DUAN, Project Assistant Professor Sakai lab, Department of Nuclear Engineering and Management, received “計算科学技術部会 CG Award” at Atomic Energy Society of JAPAN, Spring, 2023.

〈Name of award and short explanation about the award）

“CG Award”

The award is given to the presenter who had made an outstanding visualization result at the Spring Meeting of Atomic Energy Society of Japan in 2023.

〈About awarded research）

Reducing the porosity of the parts fabricated by metal additive manufacturing is crucial to the applications in nuclear engineering and other fields. The pre-existing bubbles inside the feedstock particles are a key reason for the porosity. The bubble transfer from the powder bed to the melt pool in additive manufacturing is investigated by coupling the moving particle semi-implicit method and the discrete element method. It is found that bubble radius and laser beam shapes could significantly affect the bubble entrapment behaviors in the melt pool. The influence of round, horizontal-oval, and transverse-oval laser-beam shapes on the bubble entrapment and dischargement was investigated. Based on the discovered mechanisms of bubble entrapment and dischargement, two approaches were proposed to reduce the porosity: (a) employing a horizontal oval laser beam and (b) rescanning the solidified melt pool. The simulation results demonstrated the effectiveness of both approaches.

〈Your impression & future plan）

I am deeply honored to receive this CG award, which is a great encouragement to me. I would also like to express my sincere gratitude to Professor Mikio Sakai for his guidance and everyone in our laboratory for their valuable advice. I am truly grateful for the recognition of the organizers, and I look forward to making further research advancements in nuclear engineering in the future.