This study introduces Ti6Al4V2Fe, a novel dual-phase titanium alloy, manufactured via Cold Metal Transfer Directed Energy Deposition (CMT-DED) for aerospace applications. This alloy meets stringent performance demands and enables efficient additive manufacturing of large-scale components. We investigated its microstructural evolution and mechanical properties under static and dynamic conditions. Room temperature tensile tests and dynamic impact assessments (1500/s to 3000/s) revealed a refined microstructure with short columnar and fine equiaxed prior-β grains, influenced by undercooling and thermal gradients. The addition of Fe enhanced β phase nucleation, resulting in a basket-weave α + β structure. Dynamic tests highlighted increasing strength with strain rate, with horizontal samples displaying superior strength. A constitutive model confirmed the experimental stress-strain profiles. At 2500/s, adiabatic shear bands indicated heightened sensitivity in horizontal samples, while vertical samples absorbed more energy, linked to dynamic recrystallization. The Ti6Al4V2Fe alloy, fabricated by CMT-DED, demonstrates remarkable strength, enhanced toughness, and reduced anisotropy, marking it as a prime candidate for aerospace applications.

Additive manufacturing, particularly extrusion-based additive manufacturing (EB-AM), has transformed the fabrication of complex structures. Thermoplastic Polyurethane (TPU), valued for its elasticity and durability, is an ideal material for flexible lattice designs. However, determining optimal rheological properties and printing parameters during extrusion remains a significant challenge. This study introduces the 3DFLOR framework (3D Flexible Lattice Optimisation via Rheology), a novel methodology that combines the Doehlert experimental design and Response Surface Methodology (RSM) to minimise trial and error in EB-AM. By systematically adjusting critical printing parameters, such as printing temperature and speed, the 3DFLOR framework establishes a link between the rheological and the mechanical properties. The experimental results show an enhancement of the mechanical properties tailored for the morphing application. This research not only provides a specific application optimisation but a universal methodology for optimising and linking rheology and material properties in other applications.