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C578 Type I vs JIS A9511 EPS

Polymer · grade comparison

C578 Type I and JIS A9511 EPS are both polymer grades. JIS A9511 EPS is the stronger of the two: tensile strength 0.2 MPa (0.029 ksi) against 0.13 MPa (0.0189 ksi) for C578 Type I, about 54% more. C578 Type I is lighter (0.02 g/cm³ vs 0.02 g/cm³ for JIS A9511 EPS) and JIS A9511 EPS is stiffer (0.01 GPa vs 0 GPa).

C578 Type IChoose it when weight is the constraint.

JIS A9511 EPSChoose it when strength drives the design.

C578 Type I vs JIS A9511 EPS: properties

C578 Type IJIS A9511 EPS

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0 GPa4.35×10⁻⁴ Msi
0.01 GPa7.25×10⁻⁴ Msi

Tensile Strength (Ultimate)

0.13 MPa0.02 ksi
0.2 MPa0.03 ksi

Compressive Modulus

0 GPa4.35×10⁻⁴ Msi
0 GPa6.53×10⁻⁴ Msi

Flexural Strength

0.2 MPa0.03 ksi
0.15 MPa0.02 ksi

Shear Strength

0.09 MPa0.01 ksi
0.1 MPa0.01 ksi

Yield Strength (0.2% offset)

—
0.18 MPa0.03 ksi

Elongation at Break

—
1.5%

Flexural Modulus

—
0.01 GPa7.98×10⁻⁴ Msi

Compression Set (22 h, 70 °C)

—
4%

Same in both: Poisson's Ratio 0.1 · Compressive Strength 0.08 MPa0.01 ksi

Physical

Density and transition temperatures.

Density

0.02 g/cm³5.42×10⁻⁴ lb/in³
0.02 g/cm³7.23×10⁻⁴ lb/in³

Water Absorption (24 h)

1%
1.5%

Water Absorption (Saturation)

3%
4%

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

Thermal

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

Thermal Conductivity

0.04 W/m·K0.02 BTU/hr·ft·°F
0.04 W/m·K0.02 BTU/hr·ft·°F

Specific Heat Capacity

1,300 J/kg·K0.31 BTU/lb·°F
1,400 J/kg·K0.33 BTU/lb·°F

Min Service Temperature

-50°C-58 °F
-80°C-112 °F

Vicat Softening Point (B50)

96°C205 °F
98°C208 °F

Limiting Oxygen Index

26%
18%

Same in both: Thermal Expansion (CTE, 20–100 °C) 65 µm/m·K36.1 µin/in·°F · Max Service Temperature (continuous) 75°C167 °F · Max Service Temperature (short-term) 85°C185 °F

Electrical

Conductivity and insulation.

Dielectric Constant (1 MHz)

1.03
1.04

Surface Resistivity

1×10¹⁵ Ω
—

Electrical Resistivity

—
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in

Same in both: Dissipation Factor (1 MHz) 2×10⁻⁴ · Volume Resistivity 1×10¹⁶ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

70 / 100
80 / 100

UV / Weathering Resistance

12 / 100
15 / 100

Manufacturability

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

Machinability

85 / 100
90 / 100

Mold Shrinkage

0.4%
0.45%

Formability (cold)

—
25 / 100

Same in both: Weldability 30 / 100 · Mold Temperature (typ.) 115°C239 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

3.3 kg CO₂/kg
3.6 kg CO₂/kg

Embodied Water

190 L/kg22.8 gal/lb
165 L/kg19.8 gal/lb

Same in both: Embodied Energy (primary production) 105 MJ/kg45,142 BTU/lb · Typical Recycled Content 5%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

9 kN·m/kg
10 kN·m/kg

Specific Stiffness (E / density)

0.2 MN·m/kg
0.3 MN·m/kg

Thermal Diffusivity

2.1 mm²/s
1.4 mm²/s

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.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scaleJIS A9511 EPS

Manufacturing and finishing

CapabilityC578 Type IJIS A9511 EPS
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

C578 Type I vs JIS A9511 EPS — frequently asked

Is JIS A9511 EPS stronger than C578 Type I?

Yes. JIS A9511 EPS has a typical tensile strength of 0.2 MPa (0.029 ksi) against 0.13 MPa (0.0189 ksi) for C578 Type I — about 54% more.

Which is cheaper, C578 Type I or JIS A9511 EPS?

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 I or JIS A9511 EPS?

JIS A9511 EPS, by a small margin. Both rate excellent for machinability — 90/100 against 85/100 for C578 Type I.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C578 Type I and JIS A9511 EPS 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.