Multimaterial Laser Powder Bed Fusion of CoCrMo and NiTi Components

Laser Powder Bed Fusion (LPBF) is the most widely adopted additive manufacturing technique in the industry for producing high-quality, complex metallic components. Recent advancements in powder deposition techniques have enabled the use of LPBF for producing multi-metal parts. Among the materials of interest, cobalt-based alloys such as CoCrMo exhibit high thermal stability, superior toughness, and excellent wear resistance, properties that make them particularly suitable for aerospace and medical applications. When combined with shape memory alloys (SMAs) like NiTi, the resulting hybrid components can exhibit enhanced mechanical performance and multifunctionality. For instance, this hybrid component can be applied in Co-based hip implants, where the integration of NiTi can mitigate the detrimental stress-shielding effect through its superelastic behavior. In this study, CoCrMo and NiTi alloys are processed together using an Aconity Midi+ LPBF system equipped with an Aerosint multi-powder recoater capable of precisely depositing up to three different powders per layer. The primary challenge lies in ensuring interface integrity and managing the interdiffusion between the two materials during fabrication. The effect of the applied volumetric energy density (VED) on the microstructural and mechanical properties of the diffusion zone is investigated. Also, the local superelastic behavior of the component is characterized. The results offer valuable insight into the development of multimaterial NiTi–CoCr components with minimal interfacial defects, enabling their potential use in diverse industrial applications.