Topologically optimized mini-channel heat sinks for reduced temperature non-uniformity

•A novel additive manufacturing technique using wire-arc thermal spray was used to fabricate a heat sink with complex internal geometry.•Density-based topology optimization was implemented to minimize temperature non-uniformity on a uniformly applied heat load.•A 21% reduction in maximum temperature and 59% reduction in temperature non-uniformity was observed compared to a parallel channel layout.•Thermal spray additive manufacturing and topology optimization are a promising approach to the fabrication of liquid-cooled heat sinks with complex internal geometries.