FabDigitFabDigit

C578 Type IV vs XPS 300

Polymer · grade comparison

C578 Type IV and XPS 300 are both polymer grades. XPS 300 is the stronger of the two: tensile strength 0.45 MPa (0.0653 ksi) against 0.4 MPa (0.058 ksi) for C578 Type IV, about 12% more. C578 Type IV is lighter (0.03 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 IV forms better (poor vs not recommended).

C578 Type IVChoose it when weight is the constraint.

XPS 300Choose it when strength drives the design.

C578 Type IV vs XPS 300: properties

C578 Type IVXPS 300

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

0.01 GPa0 Msi
0.02 GPa0 Msi

Tensile Strength (Ultimate)

0.4 MPa0.06 ksi
0.45 MPa0.07 ksi

Compressive Strength

0.21 MPa0.03 ksi
0.32 MPa0.05 ksi

Compressive Modulus

0.01 GPa0 Msi
0.01 GPa0 Msi

Flexural Strength

0.35 MPa0.05 ksi
0.55 MPa0.08 ksi

Shear Strength

0.2 MPa0.03 ksi
0.25 MPa0.04 ksi

Yield Strength (0.2% offset)

—
0.3 MPa0.04 ksi

Elongation at Break

—
3%

Flexural Modulus

—
0.01 GPa0 Msi

Same in both: Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Density

0.03 g/cm³0 lb/in³
0.04 g/cm³0 lb/in³

Water Absorption (24 h)

0.1%
0.2%

Same in both: Glass Transition (Tg) 100°C212 °F · Water Absorption (Saturation) 0.5%

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

Vicat Softening Point (B50)

—
95°C203 °F

Max Service Temperature (short-term)

—
85°C185 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 70 µm/m·K38.9 µin/in·°F · Min Service Temperature -50°C-58 °F · Limiting Oxygen Index 25%

Electrical

Conductivity and insulation.

Dielectric Constant (1 MHz)

1.05
1.07

Dissipation Factor (1 MHz)

2×10⁻⁴
—

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).

Same in both: Corrosion Resistance 85 / 100 · UV / Weathering Resistance 15 / 100

Manufacturability

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

Machinability

90 / 100
92 / 100

Weldability

20 / 100
15 / 100

Formability (cold)

30 / 100
10 / 100

Polishability

5 / 100
—

Processing Melt Temperature (typ.)

—
190°C374 °F

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)

5.5 kg CO₂/kg
3.2 kg CO₂/kg

Embodied Water

—
130 L/kg15.6 gal/lb

Same in both: Typical Recycled Content 15%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

14 kN·m/kg
13 kN·m/kg

Same in both: Specific Stiffness (E / density) 0.4 MN·m/kg · Thermal Diffusivity 0.7 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 scaleXPS 300

Manufacturing and finishing

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

C578 Type IV vs XPS 300 — frequently asked

Is XPS 300 stronger than C578 Type IV?

Yes. XPS 300 has a typical tensile strength of 0.45 MPa (0.0653 ksi) against 0.4 MPa (0.058 ksi) for C578 Type IV — about 12% more.

Which is cheaper, C578 Type IV 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.

Which welds better, C578 Type IV or XPS 300?

C578 Type IV. Its weldability rates poor (20/100) against poor (15/100) for XPS 300.

Ready to make it?

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