D. Cormier, O. L. A. Harrysson, O. Cansizoglu, H. West, North Carolina State University, Raleigh, NC
Titanium lattice block structures fabricated via Electron Beam Melting (EBM) have received considerable interest in recent years. Lattice block structures have significant potential to reduce the weight of aerospace structures with minimal reduction of mechanical properties. However, the design and fabrication of titanium lattice block structures is not trivial. To date, examples involving simple rectangular lattice blocks have been routinely demonstrated. Real aerospace parts, however, will require the integration of both solid and lattice block regions. The first section of this talk will address design guidelines for integrating lattice blocks within solid structures such that powder can be removed. The second section of the talk will address the performance of a variety of titanium lattice block geometric structures fabricated via the EBM process. The relative density, and hence weight reduction, of a lattice block can be controlled by varying the unit cell type, the unit cell size, and/or the diameter of the struts that make up the cellular matrix. The manner in which the lattice structure is designed and the orientation with which it is fabricated can significantly affect mechanical performance. There is very little publically available test data that documents the relationship between lattice block geometry and mechanical properties. This talk will provide test results of considerable practical value to mechanical designers considering the use of lattice block structures.
Summary: This talk provides guidelines on how to design Electron Beam Melted titanium lattice block structures for ease of additive manufacture. It then presents data that shows the weight reduction achievable with different titanium lattice structure geometries, and it also shows the corresponding mechanical properties.
