FabDigitFabDigit

C/SiC vs LAS/SiC

Composite · grade comparison

C/SiC and LAS/SiC are both composite grades. LAS/SiC is the stronger of the two: tensile strength 260 MPa (37.7 ksi) against 150 MPa (21.8 ksi) for C/SiC, about 73% more. LAS/SiC is the more ductile: elongation 0.7% versus 0.3% for C/SiC. C/SiC is lighter (2.1 g/cm³ vs 2.5 g/cm³ for LAS/SiC) and LAS/SiC is stiffer (110 GPa vs 65 GPa).

C/SiCChoose it when weight is the constraint, or when the part sees heat.

LAS/SiCChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

C/SiC vs LAS/SiC: properties

C/SiCLAS/SiC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

65 GPa9.4 Msi
110 GPa16 Msi

Shear Modulus

25 GPa3.6 Msi
42 GPa6.1 Msi

Poisson's Ratio

0.17
0.22

Tensile Strength (Ultimate)

150 MPa21.8 ksi
260 MPa37.7 ksi

Elongation at Break

0.3%
0.7%

Compressive Strength

500 MPa72.5 ksi
800 MPa116 ksi

Flexural Strength

220 MPa31.9 ksi
400 MPa58 ksi

Flexural Modulus

70 GPa10.2 Msi
105 GPa15.2 Msi

Shear Strength

28 MPa4.1 ksi
45 MPa6.5 ksi

Bulk Modulus

—
70 GPa10.2 Msi

Compressive Modulus

—
110 GPa16 Msi

Same in both: Fracture Toughness (K_IC) 15 MPa·√m13.7 ksi·√in

Physical

Density and transition temperatures.

Density

2.1 g/cm³0.08 lb/in³
2.5 g/cm³0.09 lb/in³

Water Absorption (24 h)

0.2%
0.3%

Thermal

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

Thermal Conductivity

20 W/m·K11.6 BTU/hr·ft·°F
2.5 W/m·K1.4 BTU/hr·ft·°F

Specific Heat Capacity

750 J/kg·K0.18 BTU/lb·°F
900 J/kg·K0.21 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

2.5 µm/m·K1.4 µin/in·°F
3 µm/m·K1.7 µin/in·°F

Max Service Temperature (continuous)

1,350°C2,462 °F
900°C1,652 °F

Max Service Temperature (short-term)

1,650°C3,002 °F
1,200°C2,192 °F

Same in both: Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

0.001 Ω·m39,370 µΩ·in
1 Ω·m3.94×10⁷ µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

80 / 100
78 / 100

UV / Weathering Resistance

100 / 100
98 / 100

Manufacturability

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

Machinability

10 / 100
8 / 100

Polishability

60 / 100
45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

700 MJ/kg300,946 BTU/lb
320 MJ/kg137,575 BTU/lb

Embodied Carbon (primary production)

45 kg CO₂/kg
26 kg CO₂/kg

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

71 kN·m/kg
104 kN·m/kg

Specific Stiffness (E / density)

31 MN·m/kg
44 MN·m/kg

Thermal Diffusivity

12.7 mm²/s
1.1 mm²/s

Thermal Shock Resistance Index

18
2

Strength versus weight

Yield strength against density for every composite grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

1101001,000510Density (g/cm³)Yield strength (MPa) — log scale

Manufacturing and finishing

CapabilityC/SiCLAS/SiC
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

C/SiC vs LAS/SiC — frequently asked

Is LAS/SiC stronger than C/SiC?

Yes. LAS/SiC has a typical tensile strength of 260 MPa (37.7 ksi) against 150 MPa (21.8 ksi) for C/SiC — about 73% more.

Which is cheaper, C/SiC or LAS/SiC?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

When should I choose C/SiC over LAS/SiC?

Pick C/SiC when weight is the constraint, or when the part sees heat. Pick LAS/SiC when strength drives the design, or when the part is bent, formed or impact-loaded.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C/SiC and LAS/SiC 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.