When to pick this combination
Pick SLS PA12 when you need a qualified polymer-AM workhorse with the widest material catalog (flame-retardant, ESD-safe, food-contact variants) and a broad service-bureau supply chain. MJF gives tighter Z-direction properties; SLS gives broader material choice.
- Functional polymer parts in qualified-material grades
- Flame-retardant variants for aerospace interiors
- ESD-safe variants for electronics
- Food-contact variants for handling fixtures
Typical defects and how the model accounts for them
Layer-bonding scatter is higher than MJF; Z-direction strength runs 60–75% of X-Y. Powder ages with each cycle, so refresh rates ≥ 50% virgin are typical for fatigue-critical work.
Required post-processing
The allowables above assume the full post-processing chain. Skipping any step degrades the row by 15–35 %.
- Cool in cake to 50 °C
- Bead-blast
- Optional vapour-smooth for sealed surfaces
- Optional dye
Suggested build parameters
Starting recipe; tune against first-article inspection on geometry-sensitive features.
- Layer: 100 μm
- Laser: 30 W CO₂
- Build chamber: 170 °C
- Powder refresh: ≥ 50% virgin
Frequently asked questions
MJF vs SLS PA12 — which?
MJF is faster and more isotropic on plain PA12; SLS wins when you need a qualified variant (FR, ESD, food) that HP MJF doesn't yet ship.
Sources
- EOS PA 2200 (PA12) material data sheet
- ASTM F3001 (general AM nomenclature)