Powder Technology: Near-Net Shape Forming of Inconel 718 via Selective Powder Deposition and Spark Plasma Sintering Achieves Core Density Over 96%

On September 25, 2026, BioNovel reported on a new study in the journal Powder Technology: combining selective powder deposition (SPD) with spark plasma sintering (SPS) for near-net shape forming of complex-shaped metal components—metal powder and alumina space-holding material are co-deposited in designed patterns, directly building three-dimensional multi-material powder structures within the SPS die, breaking through the limitation of conventional SPS graphite dies with fixed geometries that can only produce simple disks. Key conclusions: Near-net shape forming requires densification-enhancing strategies to achieve relative densities above 95%; fully encapsulated structures have limited densification, while shell designs can increase core relative density to over 96%; electrically insulating configurations reduce thermal gradients and make temperature fields more uniform; the study used copper and Inconel 718 as validation materials, demonstrated geometric feasibility and material transferability through gear and propeller demonstrators, and established a master sintering curve (MSC) and a PID thermal-electrical coupling model. Industry resonance: Dr. Bram Neirinck of Schaeffler Aerosint reported at the Sintering 2026 international conference on the development of sintering methods for near-net shape forming of copper via selective powder deposition, indicating that this technological direction is attracting joint attention from industry and academia; the SPD process has strict requirements on powder flowability and particle size and has limited spatial resolution, which are the main current engineering challenges. Value to powder buyers: ① The SPD-SPS route has stringent requirements on powder flowability and particle size distribution, driving powder manufacturers to provide narrow particle size classified products; ② If near-net shape forming of Inconel 718/copper components is scaled up, it will create new procurement scenarios for high sphericity, low oxygen content powders; ③ The space-holding material (alumina) is a consumable auxiliary material, deriving supporting supply opportunities.