Additive Manufacturing of Ni‐Based Thermoelectric Materials for Waste Heat Recovery

ABSTRACT Thermoelectric (TE) generators convert waste heat into electricity but are limited by conventional manufacturing methods that restrict design flexibility and scalability. Additive manufacturing, particularly laser powder bed fusion (LPBF), offers a solution by enabling the direct fabrication of complex customised geometries. In this study, we successfully fabricated cuboid thermoelectric legs from n‐type Cu ₆₀ Ni ₄₀ and p‐type Ni ₉₀ Cr ₁₀ (at.%) using LPBF. We systematically investigated the effects of laser scan speed and power on density, as well as the impact of laser scan speed on microstructure and thermoelectric performance. Higher scan speeds increased porosity, reduced grain size, and significantly lowered thermal conductivity. By modifying process parameters, Cu ₆₀ Ni ₄₀ achieved a 62% reduction in thermal conductivity, with a peak zT of 0.21 at 673 K. Additionally, a module was assembled using the LPBF‐fabricated legs, achieving a maximum conversion efficiency of 0.8% at a temperature difference of 419 K. These results demonstrate the potential of LPBF to tailor thermoelectric properties in abundant, eco‐friendly materials, advancing TE generators design through additive manufacturing.