A focused review and proof-of-concept for metal deposition on polymer substrates via laser processing in additive manufacturing

The integration of metals onto polymer substrates enables the realization of multifunctional structures that combine lightweight characteristics. Among various approaches, laser-based metal deposition offers a direct and efficient route to fabricate polymer–metal hybrid components without conventional joining processes. However, this approach remains challenging due to the substantial mismatch in thermal and physical properties between metals and polymers. In Section “Introduction”, the background and motivation for polymer–metal hybrid structures are introduced. Section “Existing studies of metal deposition on polymer” reviews recent studies on laser-based metal deposition on polymer substrates and summarizes their key findings and limitations. Section “Challenges and future research directions” discusses the major challenges, including thermal mismatch, interfacial bonding limitations, and narrow processing windows. In Section “Proof-of-concept study”, a proof-of-concept study is presented using CoCrMo powder deposited on polyetheretherketone and polylactic acid substrates under CO 2 laser irradiation, demonstrating the trade-off between insufficient bonding and thermal degradation, as well as material-dependent bonding behavior. Notably, for PLA, stable particle embedding was achieved without noticeable carbonization, and increasing the number of coating sets from one to three reduced the surface roughness from 10.88 to 4.90 μm under the representative laser condition of 8.6 W and 150 mm/s. Finally, Section “Concluding remarks” summarizes the key findings from both the focused review and proof-of-concept study, with an emphasis on future research directions. Overall, this study provides a concise overview of current progress and limitations, and suggests potential directions for advancing polymer–metal hybrid additive manufacturing.