Advances and perspectives in multi-material additive manufacturing of heterogenous metal-polymer components

Metal-polymer heterogeneous architectures enable the integration of mechanical, electrical, and thermal functionalities within a single structure, offering new possibilities in multifunctional systems. With advances in multi-material additive manufacturing (MMAM), it is now feasible to fabricate complex hybrid structures with high spatial resolution by combining dissimilar materials. This review highlights recent innovations across two key fabrication categories: direct printing and hybrid manufacturing. Emerging single-step printing processes, such as electrical field-assisted heterogeneous material printing and polymer-assisted photochemical deposition, allow precise metal patterning on polymers. Hybrid approaches—including electroplating and electroless plating—enhance surface robustness and conductivity through post-processing integration. Alternative strategies like mechanical interlocking, thermomechanical joining, and AddJoining address adhesion challenges in structural applications. These techniques are assessed for process scalability, material compatibility, and functional performance. The review concludes by identifying critical challenges and outlining future research directions toward scalable, high-performance, and sustainable metal-polymer hybrid systems enabled by next-generation MMAM technologies.