Material isn’t just a technical spec – it determines whether the product survives real-world use. We review three leading engineering materials, their properties, and the applications where each one wins.
PA12 (Nylon 12) – the workhorse
PA12 is the most common material in SLS and MJF printing. It offers an excellent balance of strength, flexibility and chemical resistance. Withstands up to 130°C, absorbs little moisture, and suits nearly any mechanical application.
- Mechanism housings, hinges, brackets
- End-use series of hundreds of units
- Industrial-scale parts at reasonable cost
ULTEM (PEI) – the aerospace standard
ULTEM is polyetherimide (PEI) rated for continuous use to 170°C, with flame, radiation and aggressive-chemical resistance. It is certified to FAR 25.853 – the standard for aircraft interior parts. Drawback: price. ULTEM 9085 costs 8x more than PA12.
- Air ducts and interior panels in aircraft
- Medical equipment that undergoes autoclave sterilization
- Housings for hot electronics
TPU – flexibility without compromise
TPU (Thermoplastic Polyurethane) is an elastomer – flexible like rubber but printable. Shore hardness between 70A and 95A, excellent tear and abrasion resistance. Classic uses: seals, grip handles, shoe soles.
Quick comparison
- Mechanical strength: ULTEM > PA12 > TPU
- Heat resistance: ULTEM (170°C) > PA12 (130°C) > TPU (80°C)
- Flexibility: TPU >> PA12 > ULTEM
- Per-unit cost: ULTEM >> PA12 ≈ TPU
Final recommendation
Always start with PA12 – if it meets requirements, stop. Move to ULTEM only when temperature or standards demand. Pick TPU only when the function genuinely requires flexibility. Review the FMEA before upgrading material.