Topology Optimization for Metal Additive Manufacturing: Constraints, Challenges, and Emerging Solutions

Engineering components used in the fields of aerospace, automotive, and biomedical engineering need to exhibit lightness and strength. Balancing lightness and mechanical strength is necessary to improve performance while reducing total system weight and energy consumption. Additive Manufacturing (AM), along with Topology Optimization (TO), may present solutions for achieving these requirements through creating high-performance, low-weight geometries which cannot be produced via conventional manufacturing techniques. This review paper, which reviews academic literature published between the years of 2015 and 2025, examines the limitations and associated solutions for designing mechanical components optimized for AM, including overhang limitations or constraints and minimizing support structures, anisotropy and orientations when building, self-weight, and performance versus fatigue. Overall, TO for Metal AM produces designs with less weight and greater structural integrity while producing structures that do not require additional supports. While there have been many positive results from TO for Metal AM, it has limited use due to high costs and complexity of implementation, suggesting the need for further development in this space to make it more applicable.