C578 Type XI vs EPS 150
Polymer · grade comparison
C578 Type XI and EPS 150 are both polymer grades. EPS 150 is the stronger of the two: tensile strength 0.3 MPa (0.0435 ksi) against 0.08 MPa (0.0116 ksi) for C578 Type XI, about 3.8 times as much. In exchange, C578 Type XI is the more ductile: elongation 2.5% versus 2% for EPS 150. C578 Type XI is lighter (0.01 g/cm³ vs 0.03 g/cm³ for EPS 150) and EPS 150 is stiffer (0.01 GPa vs 0 GPa). On the shop floor, EPS 150 machines more easily (excellent vs good) and EPS 150 welds better (fair vs poor).
C578 Type XIChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.
EPS 150Choose it when strength drives the design, or when the part is machined in volume.
C578 Type XI vs EPS 150: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Shear Modulus
Yield Strength (0.2% offset)
Compression Set (22 h, 70 °C)
Same in both: Poisson's Ratio 0.1
Physical
Density and transition temperatures.
Density
Same in both: Glass Transition (Tg) 100°C212 °F · Water Absorption (24 h) 1% · Water Absorption (Saturation) 3.5%
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Max Service Temperature (continuous)
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Thermal Expansion (CTE, 20–100 °C) 65 µm/m·K36.1 µin/in·°F · Min Service Temperature -50°C-58 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Volume Resistivity
Dissipation Factor (1 MHz)
Same in both: Dielectric Constant (1 MHz) 1.03
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Mold Shrinkage
Processing Melt Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Water
Same in both: Embodied Carbon (primary production) 3.3 kg CO₂/kg · Typical Recycled Content 5%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 0
Strength versus weight
Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | C578 Type XI | EPS 150 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
C578 Type XI vs EPS 150 — frequently asked
Is EPS 150 stronger than C578 Type XI?
Yes. EPS 150 has a typical tensile strength of 0.3 MPa (0.0435 ksi) against 0.08 MPa (0.0116 ksi) for C578 Type XI — about 3.8 times as much.
Which is cheaper, C578 Type XI or EPS 150?
Both sit in the same relative cost tier ($$, standard); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, C578 Type XI or EPS 150?
EPS 150. Its machinability rates excellent (88/100) against good (55/100) for C578 Type XI; for welding the order is EPS 150 first (fair, 40/100) then C578 Type XI (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C578 Type XI and EPS 150 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.