Embedded multilayer strain architectures create self-sensing multifunctional titanium in additive manufacturing

Multifunctional structural metals capable of monitoring their internal mechanical state are increasingly important for aerospace, biomedical, and intelligent manufacturing applications, yet integrating thermally sensitive sensing architectures into high-temperature metal additive manufacturing remains challenging. Here we show that multilayer strain sensing architectures can be embedded directly within Ti-6Al-4V during laser powder bed fusion by combining high-resolution printing of polymer–metal gauges with powder mediated thermal protection. We evaluate four sensor architectures, including commercial foil gauges and directly printed gauges with different dielectric layers, and identify material stacks that survive embedding while retaining electrical functionality. The embedded sensors preserve strain sensing performance under mechanical loading, maintain structural integrity, and exhibit cytocompatibility. These results establish a route to multifunctional titanium with internal sensing capability and provide a materials integration framework for embedding functional devices within additively manufactured metals.