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C578 Type IX vs EPS 150

Polymer · grade comparison

C578 Type IX and EPS 150 are both polymer grades. C578 Type IX is the stronger of the two: tensile strength 0.35 MPa (0.0508 ksi) against 0.3 MPa (0.0435 ksi) for EPS 150, about 17% more. EPS 150 is lighter (0.03 g/cm³ vs 0.03 g/cm³ for C578 Type IX) and EPS 150 is stiffer (0.01 GPa vs 0.01 GPa). On the shop floor, EPS 150 welds better (fair vs poor) and C578 Type IX forms better (fair vs poor).

C578 Type IXChoose it when strength drives the design.

EPS 150Choose it when weight is the constraint, or when it will be welded.

C578 Type IX vs EPS 150: properties

C578 Type IXEPS 150

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0.01 GPa8.7×10⁻⁴ Msi
0.01 GPa0 Msi

Shear Modulus

0 GPa4.06×10⁻⁴ Msi
0 GPa5.8×10⁻⁴ Msi

Tensile Strength (Ultimate)

0.35 MPa0.05 ksi
0.3 MPa0.04 ksi

Compressive Strength

0.19 MPa0.03 ksi
0.16 MPa0.02 ksi

Compressive Modulus

0.01 GPa7.98×10⁻⁴ Msi
0.01 GPa0 Msi

Flexural Strength

0.55 MPa0.08 ksi
0.28 MPa0.04 ksi

Shear Strength

0.16 MPa0.02 ksi
0.14 MPa0.02 ksi

Yield Strength (0.2% offset)

—
0.15 MPa0.02 ksi

Elongation at Break

—
2%

Flexural Modulus

—
0.01 GPa0 Msi

Compression Set (22 h, 70 °C)

—
8%

Same in both: Poisson's Ratio 0.1

Physical

Density and transition temperatures.

Density

0.03 g/cm³0 lb/in³
0.03 g/cm³0 lb/in³

Water Absorption (24 h)

1.5%
1%

Water Absorption (Saturation)

4%
3.5%

Same in both: Glass Transition (Tg) 100°C212 °F

Thermal

How each material carries heat and how hot it can run.

Max Service Temperature (continuous)

75°C167 °F
80°C176 °F

Min Service Temperature

-80°C-112 °F
-50°C-58 °F

Max Service Temperature (short-term)

95°C203 °F
100°C212 °F

Vicat Softening Point (B50)

—
96°C205 °F

Same in both: Thermal Conductivity 0.03 W/m·K0.02 BTU/hr·ft·°F · Specific Heat Capacity 1,400 J/kg·K0.33 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 65 µm/m·K36.1 µin/in·°F · Limiting Oxygen Index 25%

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
1×10¹³ Ω·m3.94×10²⁰ µΩ·in

Dielectric Constant (1 MHz)

1.04
1.03

Volume Resistivity

1×10¹⁶ Ω·cm
1×10¹⁵ Ω·cm

Same in both: Dissipation Factor (1 MHz) 3×10⁻⁴

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

20 / 100
12 / 100

Corrosion Resistance

—
58 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

85 / 100
88 / 100

Weldability

20 / 100
40 / 100

Formability (cold)

45 / 100
25 / 100

Mold Shrinkage

0.6%
0.4%

Processing Melt Temperature (typ.)

—
115°C239 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

100 MJ/kg42,992 BTU/lb
95 MJ/kg40,843 BTU/lb

Embodied Carbon (primary production)

3.4 kg CO₂/kg
3.3 kg CO₂/kg

Embodied Water

200 L/kg24 gal/lb
190 L/kg22.8 gal/lb

Same in both: Typical Recycled Content 5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

12 kN·m/kg
11 kN·m/kg

Specific Stiffness (E / density)

0.2 MN·m/kg
0.3 MN·m/kg

Same in both: Thermal Diffusivity 0.8 mm²/s · 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.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scaleEPS 150

Manufacturing and finishing

CapabilityC578 Type IXEPS 150
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

C578 Type IX vs EPS 150 — frequently asked

Is C578 Type IX stronger than EPS 150?

Yes. C578 Type IX has a typical tensile strength of 0.35 MPa (0.0508 ksi) against 0.3 MPa (0.0435 ksi) for EPS 150 — about 17% more.

Which is cheaper, C578 Type IX 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 welds better, C578 Type IX or EPS 150?

EPS 150. Its weldability rates fair (40/100) against poor (20/100) for C578 Type IX.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C578 Type IX 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.