GOALI: Novel Computational Approaches to Address Key Design Optimization Issues for Metal Additive Manufacturing

添加制造(AM)，也被称为3D打印，现在能够制造出足够坚固的复杂形状的金属部件，以满足结构应用。AM制造复杂几何形状的能力消除了许多传统制造限制，极大地扩展了设计空间。然而，当前阻碍AM和拓扑优化结合的关键问题有：1)由于其高度复杂的形状，难以加工拓扑优化的AM部件；2)无法针对残余应力和变形优化AM零件的设计。这个GOALI学术联络机会(GOALI)研究项目旨在建立一种强大的拓扑优化技术，能够解决添加剂制造(AM)部件的残余变形、残余应力和加工后要求。开发的技术将大大缩短AM新产品开发的设计阶段，这可能会导致美国制造基地更广泛地采用AM。学生通过这个项目获得的技能和知识将为他们在确保美国在未来几代工程设计和先进制造领域的领导地位方面发挥积极作用做好准备。这个目标项目的目标是通过提出和研究两种新的方法来解决上述关键的设计问题。第一种方法是基于固有应变理论的超高速计算方法，用于预测AM零件的残余应力和变形。第二种方法是一种基于水平集特征的拓扑优化方法，能够生成自由曲面和加工友好曲面的设计。这些方法将使用我们的工业合作伙伴Aerotech提供的真实部件和设计要求进行开发和测试。利用这种方法，将开发一种稳健的拓扑优化方法，以优化AM设计的残余应力、残余变形和加工后要求。

The additive manufacturing (AM), also called 3D printing, process is now capable of manufacturing complex-shaped metal components strong enough for structural applications. The capability of AM to fabricate complex geometries removes many conventional manufacturing constraints and largely expands the design space. However, there are key current issues that are impeding the marriage between AM and topology optimization: 1) Difficulty in machining topology optimized AM components due to their highly complex shapes, and 2) Inability to optimize AM part design for residual stress and distortion. This Grant Opportunity for Academic Liaison with Industry (GOALI) research project aims at establishing a robust topology optimization technology capable of accounting for residual distortion, residual stress, and post-machining requirements for additive manufactured (AM) components. The technology developed will significantly shorten the design phase during new AM product development, which will potentially lead to wider adoption of AM by the manufacturing base in the US. The skills and knowledge the students gain through this project will prepare them for active roles in securing U.S. leadership in engineering design and advanced manufacturing for future generations.The goal of this GOALI project is to address the aforementioned critical design issues by proposing and investigating two novel approaches. The first approach is an ultra-fast computational method based on the inherent strain theory for predicting residual stress and distortion in an AM part. The second approach is a level set feature-based topology optimization method capable of generating designs with both freeform surfaces and machining-friendly surfaces. These approaches will be developed and tested using real parts and design requirements provided by our industrial partner Aerotech. Utilizing this approach, a robust topology optimization method will be developed to optimize AM designs for residual stress, residual distortion, and post-machining requirements.