Mechanical Resistance Comparison & Executive Summary

Across leading high‑strength photopolymers, 3Dresyn PEEK‑like delivers a balanced, real‑world mechanical profile:

  • Elite flexural strength: 120–140 MPa (same class as top rigid composites)

  • High impact toughness: >30 J/m (helps prevent cracking and chipping)

  • Low density: ~1.0–1.1 g/cm³ (superior strength‑to‑weight)

  • High heat performance: HDT >110 °C @ 1.8 MPa; >120 °C @ 0.45 MPa

  • Open‑system compatibility: 385/405 nm SLA, DLP, LCD/MSLA

Choose resistance, not just stiffness. 3Dresyn PEEK‑like pairs elite flexural strength (120–140 MPa) with >30 J/m impact toughness at ~1.0–1.1 g/cm³, delivering a higher strength‑to‑weight than ultra‑stiff composites. Add HDT >110 °C @ 1.8 MPa and open‑system compatibility for lighter, tougher, heat‑ready parts—built for real engineering use, not just test coupons.

This balance reduces brittle failures and fatigue in functional parts compared to competitors that prioritize peak MPa at the expense of toughness and weight.

Data Table — Flexural Strength & Key Traits (post‑cure unless noted)

Resin Flexural Strength Noted Traits
3Dresyn PEEK‑like 120–140 MPa >30 J/m Izod, ~1.0–1.1 g/cm³, HDT >110 °C @1.8 MPa; open 385/405 nm. Balanced: strength + toughness + heat.
Liqcreate Composite‑X 140–170 MPa (with thermal bake) Very stiff (~9–9.5 GPa), dense (1.62 g/cm³) → high peak MPa but more brittle; open systems.
Formlabs Rigid 10K 126–158 MPa Ultra‑stiff (~10 GPa), lower toughness; closed ecosystem.
3D Systems Accura HPC 137–157 MPa High‑rigidity composite for jigs/WT models (SLA, closed).
3D Systems Accura CeraMAX 137–145 MPa Ceramic‑reinforced, very rigid (SLA, closed).
3D Systems Accura Bluestone 124–154 MPa Nano‑composite, very high stiffness (SLA, closed).
Stratasys Somos PerFORM 120–146 MPa Rigid, high‑temp composite; lower toughness (closed).
3D Systems Accura Composite PIV ~142 MPa class Rigid, high‑contrast PIV tooling (SLA, closed).
Carbon EPX 86FR ~140 MPa class FR, high strength; Carbon closed platform.
Liqcreate Strong‑X 134–135 MPa Strong, stiff; open systems.
Henkel Loctite 3955 HDT280 FST ~138 MPa FR/FST + very high HDT (thermal cure); typically stiffer/brittle; partner ecosystems.
Nexa3D xPEEK147 111–134 MPa High‑temp (HDT ~230 °C), strong; Nexa3D platform.
Carbon CE 221 (cyanate‑ester) ~130 MPa (often at 5% strain) Very high HDT, rigid; Carbon platform.
Carbon EPX 150 ~123 MPa High heat (HDT ~155 °C), balanced; Carbon platform.
Carbon EPX 82 ~120–130 MPa (often at 5% strain) Durable epoxy; Carbon platform.
Forward AM Ultracur3D RG 3280 (strength varies) Extremely high stiffness (~10 GPa), very high HDT; ceramic‑filled; partner ecosystems.
Formlabs Grey Pro ~121 MPa / ~86 MPa at 5% strain (older TDS) General engineering; lower flexural than top tier; closed ecosystem.

Note on comparability: Some brands report stress at fixed strain (e.g., 5%) rather than maximum flexural strength. Several headline values require thermal post‑cure. Normalize when comparing.

Where 3Dresyn PEEK‑like Wins

1) Mechanical Resistance in Real Parts (Toughness + Strength‑to‑Weight)

  • Impact toughness: >30 J/m notched Izod—significantly higher than typical ultra‑stiff composites (often ~16–20 J/m). This reduces crack initiation during handling, assembly, and drops.

  • Strength‑to‑weight: With ~1.0–1.1 g/cm³ density, PEEK‑like achieves specific flexural strength that rivals or exceeds heavier composites (e.g., ~1.6 g/cm³). Lighter parts improve ergonomics and reduce inertia‑related stress.

2) Heat + Durability, Not Just Stiffness

  • HDT >110 °C @ 1.8 MPa supports load at elevated temperatures—crucial for tooling near motors, enclosures, and thermal cycling—without brittle failure. Many “strongest” resins prioritize modulus and headline MPa, then require bake and can remain brittle.

3) Open‑System Compatibility & Process Agility

  • PEEK‑like runs on open 385/405 nm SLA/DLP/LCD printers (including MSLA). Multiple high‑MPa contenders are locked to proprietary ecosystems (e.g., Formlabs, Carbon, Stratasys, various 3D Systems Accura grades).

Application Guidance

  • Functional housings, snap‑fits, fixtures with shock/assembly loads3Dresyn PEEK‑like: strength + toughness + heat yields longer‑lasting parts and fewer brittle failures.

  • Wind‑tunnel models, ultra‑stiff jigs, high‑modulus inserts → Consider Composite‑X, Accura HPC/CeraMAX/Bluestone, or Rigid 10K where stiffness dominates and brittleness can be mitigated by design.

  • Very high‑temperature exposuresxPEEK147, CE221, Loctite 3955, RG 3280 offer extreme HDT; check printer access, brittleness, and post‑cure requirements.

Normalization & Caveats (for fair comparisons)

  • ASTM D790 vs. ISO 178: Some data report max flexural strength, others stress at 5% strain (often higher for rigid resins). Normalize to maximum where possible.

  • Thermal bake: Several materials list headline MPa after thermal post‑cure. Compare to your actual post‑cure process.

  • Platform lock‑in: Some high‑MPa grades are printer‑locked. PEEK‑like remains open‑system.

References