Slurry-based binder jetting (SBBJ) is a high-throughput, scalable additive manufacturing route that unlocks new applications by extending binder jetting to ultrafine, otherwise non-flowable powders or such that present a fire and explosion hazard in dry state. By formulating d50 ≈ 5 µm particles as high-solids slurries (~72 wt%), layerwise deposition with subsequential drying induces capillary-driven consolidation, raising green density to about 62% and substantially improving sinterability. A thermally curable binder and a minor PEG-400 addition enable reliable powder-cake washout and preserve intricate internal features [1]. The slurry route also yields smooth surfaces that often reduce or eliminate post-processing, enabling near-net-shape fabrication of complex components such as pure aluminum heat sinks sintered in argon atmosphere [2].

Economically, SBBJ delivers high build rates via large building volumes and scalable printheads, support-free fabrication within the powder cake, low material waste with easy reuse of unbound feedstock, and reduced machining thanks to near-net-shape accuracy and fine surface quality [3]. The absence of high-energy lasers or vacuum hardware lowers capital and operating costs and supports large build volumes for cost-effective series production. Beyond productivity, the slurry approach broadens accessible material systems: it processes ultrafine and oxidation-sensitive metals (e.g., commercially pure aluminum) that are challenging in dry powder beds, enables particle-reinforced and ceramic-dispersed metal matrices through tailored suspensions, and opens paths to graded or multimaterial architectures via controlled slurry formulation. These capabilities translate into new application spaces across thermal management and fluidics—compact TPMS heat exchangers, heat sinks, cold plates, and conformal cooling channels for power electronics, EV batteries, fuel cells, and aerospace—alongside lightweight lattices with tuned porosity for energy absorption, filtration, and catalytic substrates. However, tight control of slurry rheology, drying, and washout is required to prevent defects in delicate internal features, alongside robust shrinkage compensation and QA for serial production. These perspectives will be discussed in the talk, using a highly complex heat sink demonstrator produced via SBBJ from commercially pure aluminum as a case study.

References
[1] Angenoorth, J., Wächter, D., Volk, W. et al. Impact of disintegrating agents on the wash-out process for 3D-printed aluminum green parts produced by slurry-based binder jetting. Prog Addit Manuf 10, 4085–4093 (2025). https://doi.org/10.1007/s40964-025-01077-6
[2] Angenoorth, J., Erhard, P., Wächter, D. et al. Sintering of 3D-printed aluminum specimens from the slurry-based binder jetting process. Prog Addit Manuf 9, 633–642 (2024). https://doi.org/10.1007/s40964-024-00657-2
[3] Erhard, P. (2023). Slurry-based 3D printing of ceramic casting cores. Dissertation. Technical University of Munich. https://mediatum.ub.tum.de/doc/1697749/document.pdf