2023-10-16 オークリッジ国立研究所(ORNL)
◆この技術は、自動車、航空宇宙、クリーンエネルギー、工具および金型など、高性能部品を必要とする産業に応用できます。この研究は、ORNLのSpallation Neutron SourceのVULCANビームラインで行われ、材料の内部をリアルタイムで観察することを可能にします。研究者たちは、この技術が残留応力をカスタマイズし、部品の強度を向上させ、複雑な形状を実現するのに役立つことを示し、R&D 100 Awardを受賞しました。
＜関連情報＞
- https://www.ornl.gov/news/neutrons-see-stress-3d-printed-parts-advancing-additive-manufacturing
- https://www.nature.com/articles/s41467-023-40456-x
オペランド中性子回折が3Dプリンティングにおける制御されたひずみ進化のメカニズムを解明 Operando neutron diffraction reveals mechanisms for controlled strain evolution in 3D printing
A. Plotkowski,K. Saleeby,C. M. Fancher,J. Haley,G. Madireddy,K. An,R. Kannan,T. Feldhausen,Y. Lee,D. Yu,C. Leach,J. Vaughan & S. S. Babu
Nature Communications Published:16 August 2023
DOI:https://doi.org/10.1038/s41467-023-40456-x
Abstract
Residual stresses affect the performance and reliability of most manufactured goods and are prevalent in casting, welding, and additive manufacturing (AM, 3D printing). Residual stresses are associated with plastic strain gradients accrued due to transient thermal stress. Complex thermal conditions in AM produce similarly complex residual stress patterns. However, measuring real-time effects of processing on stress evolution is not possible with conventional techniques. Here we use operando neutron diffraction to characterize transient phase transformations and lattice strain evolution during AM of a low-temperature transformation steel. Combining diffraction, infrared and simulation data reveals that elastic and plastic strain distributions are controlled by motion of the face-centered cubic and body-centered cubic phase boundary. Our results provide a new pathway to design residual stress states and property distributions within additively manufactured components. These findings will enable control of residual stress distributions for advantages such as improved fatigue life or resistance to stress-corrosion cracking.
