Metal-metal composites are a special category of metal matrix composites, where an alloy is dispersed within the matrix of another alloy, resulting in structures with modified properties according to the properties of the combined materials. Although, several fabrication processes are available for the fabrication of such structures, including extensive plastic deformation and powder metallurgy [1,2], Additive Manufacturing (AM) can set new horizons for their fabrication, given the unique geometrical complexity and the microstructural characteristics of 3D printed structures. In our study, a prototype process route is proposed for the fabrication of the composite materials. AM and more specifically Laser Powder Bed Fusion (LPBF) is used for the 3D printing of lattices and strut structures from 316L stainless steel. These structures are then infiltrated with copper powder (CuCrZr), which is melted through induction melting. Through this process, copper-based composite materials are formed (figure 1), where the copper alloy is the matrix and 316L structure acts as reinforcing material with defined geometries.Emphasis is given on the interface between steel & copper, where elemental inter-diffusion (analyzed via EDS elemental mapping and simulated through DICTRA®) suggests a strong metallurgical bonding between the alloys. EBSD mapping and XRD analysis reveal the formation of a ferrite layer at the steel-copper interface. The spatial distribution of the ferrite layer was studied via polarized neutron imaging. Neutron Brag Edge Imaging allows estimating the texture of as printed 316L and composite 316L-CuCrZr structures, revealing lower texture intensity of 316L after the casting process. Tensile and compression regions captured through strain mapping are correlated with cracks depicted through neutron CT tomography. Finally, microhardness measurements across the 316L-CuCrZr interfaces and compression measurements (alongside with DIC analysis) were performed to estimate the mechanical performance of the composite materials.