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C578 Type X vs XPS 300

Polymer · grade comparison

C578 Type X and XPS 300 are both polymer grades. XPS 300 is the stronger of the two: tensile strength 0.45 MPa (0.0653 ksi) against 0.3 MPa (0.0435 ksi) for C578 Type X, about 50% more. C578 Type X is lighter (0.02 g/cm³ vs 0.04 g/cm³ for XPS 300) and XPS 300 is stiffer (0.02 GPa vs 0.01 GPa). On the shop floor, C578 Type X forms better (poor vs not recommended).

C578 Type XChoose it when weight is the constraint.

XPS 300Choose it when strength drives the design.

C578 Type X vs XPS 300: properties

C578 Type XXPS 300

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0.01 GPa0 Msi
0.02 GPa0 Msi

Shear Modulus

0 GPa5.8×10⁻⁴ Msi
—

Tensile Strength (Ultimate)

0.3 MPa0.04 ksi
0.45 MPa0.07 ksi

Compressive Strength

0.12 MPa0.02 ksi
0.32 MPa0.05 ksi

Compressive Modulus

0.01 GPa0 Msi
0.01 GPa0 Msi

Flexural Strength

0.22 MPa0.03 ksi
0.55 MPa0.08 ksi

Flexural Modulus

0.01 GPa8.7×10⁻⁴ Msi
0.01 GPa0 Msi

Shear Strength

0.14 MPa0.02 ksi
0.25 MPa0.04 ksi

Yield Strength (0.2% offset)

—
0.3 MPa0.04 ksi

Elongation at Break

—
3%

Same in both: Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Density

0.02 g/cm³7.95×10⁻⁴ lb/in³
0.04 g/cm³0 lb/in³

Water Absorption (24 h)

0.1%
0.2%

Water Absorption (Saturation)

0.3%
0.5%

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

Thermal

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

Thermal Conductivity

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

Specific Heat Capacity

1,400 J/kg·K0.33 BTU/lb·°F
1,450 J/kg·K0.35 BTU/lb·°F

Max Service Temperature (continuous)

74°C165 °F
75°C167 °F

Min Service Temperature

-60°C-76 °F
-50°C-58 °F

Limiting Oxygen Index

26%
25%

Vicat Softening Point (B50)

—
95°C203 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 70 µm/m·K38.9 µin/in·°F · Max Service Temperature (short-term) 85°C185 °F

Electrical

Conductivity and insulation.

Dielectric Constant (1 MHz)

1.05
1.07

Dissipation Factor (1 MHz)

3×10⁻⁴
—

Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Volume Resistivity 1×10¹⁶ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

12 / 100
15 / 100

Corrosion Resistance

—
85 / 100

Manufacturability

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

Machinability

90 / 100
92 / 100

Formability (cold)

20 / 100
10 / 100

Processing Melt Temperature (typ.)

200°C392 °F
190°C374 °F

Weldability

—
15 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

105 MJ/kg45,142 BTU/lb
100 MJ/kg42,992 BTU/lb

Embodied Carbon (primary production)

5 kg CO₂/kg
3.2 kg CO₂/kg

Typical Recycled Content

10%
15%

Embodied Water

—
130 L/kg15.6 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

14 kN·m/kg
13 kN·m/kg

Specific Stiffness (E / density)

0.3 MN·m/kg
0.4 MN·m/kg

Thermal Diffusivity

0.9 mm²/s
0.7 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 scaleXPS 300

Manufacturing and finishing

CapabilityC578 Type XXPS 300
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

C578 Type X vs XPS 300 — frequently asked

Is XPS 300 stronger than C578 Type X?

Yes. XPS 300 has a typical tensile strength of 0.45 MPa (0.0653 ksi) against 0.3 MPa (0.0435 ksi) for C578 Type X — about 50% more.

Which is cheaper, C578 Type X or XPS 300?

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.

When should I choose C578 Type X over XPS 300?

Pick C578 Type X when weight is the constraint. Pick XPS 300 when strength drives the design.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C578 Type X and XPS 300 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.