Binder Jetting (Metal)

Binder jet metal printing builds parts by inkjet-binding metal powder and sintering, enabling high-throughput, complex geometries with moderate tolerances and near-wrought properties after post-processing.

Overview

Binder jet metal printing creates parts by selectively jetting a liquid binder onto thin layers of metal powder, building a “green” part that is later debound and sintered. The process runs at low temperature during printing, so there are almost no thermal stresses, minimal distortion during build, and no need for support structures beyond the surrounding powder. Multiple parts can be tightly nested in a single job, making it well-suited to high part counts and complex geometries.

Choose binder jetting when you need production-level quantities of small to medium metal parts with internal channels, lattices, or details that would be expensive to machine or cast. Expect good, but not aerospace-critical, mechanical properties and surface finish, with typical density in the mid-to-high 90% range, often improved with HIP or infiltration. You trade off ultimate precision and density for faster throughput and lower cost per part. Critical interfaces usually get light finish machining or grinding after sintering to lock in tight tolerances and surface quality.

Common Materials

  • 17-4PH stainless steel
  • 316L stainless steel
  • Inconel 625
  • H13 tool steel
  • Copper

Tolerances

±0.005" to ±0.010" after sintering on well-supported features; tighter on critical surfaces with secondary machining

Applications

  • Conformal-cooled injection mold inserts
  • Lightweight structural brackets and mounts
  • Complex manifolds and fluid connectors with internal passages
  • Small heat exchangers and lattice-filled thermal components
  • Custom tooling and workholding components
  • Near-net-shape preforms for finish machining

When to Choose Binder Jetting (Metal)

Use binder jet metal printing for small to medium parts where you want complex geometry, internal channels, or lattices at low to medium production cost. It excels when you have many parts per build, moderate tolerance requirements, and you’re comfortable adding light post-machining on key features. It is a strong fit for production runs and bridge manufacturing where traditional tooling would be expensive or slow to implement.

vs Laser Powder Bed Fusion (DMLS/SLM)

Pick binder jetting over laser powder bed fusion when throughput and cost per part matter more than maximum density and tightest tolerances. Binder jetting prints much faster, nests many parts efficiently, and avoids support structures, making it attractive for series production where light post-machining can handle critical features.

vs Electron Beam Melting (EBM)

Choose binder jetting instead of EBM when you’re not locked into titanium or high-temperature alloys and you need high part counts with fine details and minimal support structures. Binder jetting runs at lower build temperatures, handles a broader range of steels, and generally offers better resolution for small, intricate components.

vs Direct Energy Deposition (DED)

Use binder jetting instead of DED when you need smaller, more detailed parts rather than large repairs or build-ups on existing components. Binder jetting provides better feature resolution, cleaner surfaces, and more predictable tolerances, while DED is better for large-format builds and on-part repairs or cladding.

vs CNC machining

Select binder jetting over CNC machining when the geometry drives up machining time or requires multiple complex setups—especially with internal channels, undercuts, or lattices. Binder jetting can deliver near-net shapes that you lightly machine only on critical surfaces, reducing material waste and cycle time.

vs Metal Injection Molding (MIM)

Go with binder jetting instead of MIM when volumes are low to medium, you want to avoid mold tooling cost, or designs may change. Binder jetting offers MIM-like part behavior and shrinkage considerations but without hard tooling, so you can iterate designs quickly and scale to moderate production.

Design Considerations

  • Model in the as-printed state and apply appropriate linear shrink factors (often 15–20%) per axis to account for sintering shrinkage; confirm values with your supplier.
  • Avoid very thin walls and long, slender features; target wall thicknesses of at least 1–1.5 mm and use ribs or fillets to stiffen tall sections against sintering distortion.
  • Provide powder escape holes and avoid fully enclosed hollow volumes so trapped powder can be removed before debinding and sintering.
  • Keep wall thickness and mass distribution as uniform as possible to reduce differential shrink and warping during sintering.
  • Add machining stock on critical surfaces and holes so the shop can finish-machine to final tolerance and surface finish.
  • Call out functional datum schemes and critical-to-function dimensions clearly so the supplier can plan fixturing, sintering supports, and finishing operations correctly.