C578 Type I vs XPS 300
Polymer · grade comparison
C578 Type I and XPS 300 are both polymer grades. XPS 300 is the stronger of the two: tensile strength 0.45 MPa (0.0653 ksi) against 0.13 MPa (0.0189 ksi) for C578 Type I, about 3.5 times as much. C578 Type I is lighter (0.02 g/cm³ vs 0.04 g/cm³ for XPS 300) and XPS 300 is stiffer (0.02 GPa vs 0 GPa). On the shop floor, C578 Type I welds better (30 vs 15 out of 100).
C578 Type IChoose it when weight is the constraint, or when it will be welded.
XPS 300Choose it when strength drives the design.
C578 Type I vs XPS 300: 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
Poisson's Ratio
Tensile Strength (Ultimate)
Compressive Strength
Compressive Modulus
Flexural Strength
Shear Strength
Yield Strength (0.2% offset)
Elongation at Break
Flexural Modulus
Physical
Density and transition temperatures.
Density
Water Absorption (24 h)
Water Absorption (Saturation)
Same in both: Glass Transition (Tg) 100°C212 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Vicat Softening Point (B50)
Limiting Oxygen Index
Same in both: Max Service Temperature (continuous) 75°C167 °F · Min Service Temperature -50°C-58 °F · Max Service Temperature (short-term) 85°C185 °F
Electrical
Conductivity and insulation.
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Surface Resistivity
Electrical Resistivity
Same in both: Volume Resistivity 1×10¹⁶ Ω·cm
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
Mold Shrinkage
Mold Temperature (typ.)
Formability (cold)
Processing Melt Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
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 I | XPS 300 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
C578 Type I vs XPS 300 — frequently asked
Is XPS 300 stronger than C578 Type I?
Yes. XPS 300 has a typical tensile strength of 0.45 MPa (0.0653 ksi) against 0.13 MPa (0.0189 ksi) for C578 Type I — about 3.5 times as much.
Which is cheaper, C578 Type I 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 is easier to machine, C578 Type I or XPS 300?
XPS 300, by a small margin. Both rate excellent for machinability — 92/100 against 85/100 for C578 Type I; for welding the order is C578 Type I first (poor, 30/100) then XPS 300 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C578 Type I 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.