FabDigit

M55J vs T300 vs T700S vs T800H

Benchmark · 4 materials

Side-by-side benchmark of 4 composite grades.

M55J vs T300 and 2 more: properties

M55JT300T700ST800H

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

540 GPa78.3 Msi
230 GPa33.4 Msi
230 GPa33.4 Msi
294 GPa42.6 Msi

Tensile Strength (Ultimate)

4,020 MPa583 ksi
3,530 MPa512 ksi
4,900 MPa711 ksi
5,490 MPa796 ksi

Elongation at Break

0.8%
1.5%
2.1%
1.9%

Compressive Strength

900 MPa131 ksi
1,570 MPa228 ksi
1,470 MPa213 ksi
2,400 MPa348 ksi

Flexural Strength

1,700 MPa247 ksi
1,620 MPa235 ksi

Shear Strength

90 MPa13.1 ksi
98 MPa14.2 ksi

Poisson's Ratio

0.27

Flexural Modulus

120 GPa17.4 Msi

Physical

Density and transition temperatures.

Density

1.91 g/cm³0.07 lb/in³
1.76 g/cm³0.06 lb/in³
1.8 g/cm³0.07 lb/in³
1.81 g/cm³0.07 lb/in³

Water Absorption (24 h)

0.1%

Thermal

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

Thermal Conductivity

155 W/m·K89.6 BTU/hr·ft·°F
10.5 W/m·K6.1 BTU/hr·ft·°F
9.4 W/m·K5.4 BTU/hr·ft·°F
35 W/m·K20.2 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

-1.1 µm/m·K-0.61 µin/in·°F
-0.41 µm/m·K-0.23 µin/in·°F
-0.38 µm/m·K-0.21 µin/in·°F
-0.56 µm/m·K-0.31 µin/in·°F

Max Service Temperature (continuous)

400°C752 °F
350°C662 °F
350°C662 °F
400°C752 °F

Same in both: Min Service Temperature -269°C-452 °F · Max Service Temperature (short-term) 500°C932 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

8×10⁻⁶ Ω·m315 µΩ·in
1.7×10⁻⁵ Ω·m669 µΩ·in
1.6×10⁻⁵ Ω·m630 µΩ·in
1.4×10⁻⁵ Ω·m551 µΩ·in

Volume Resistivity

8×10⁻⁴ Ω·cm
0 Ω·cm
0 Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

92 / 100
92 / 100
90 / 100
92 / 100

UV / Weathering Resistance

90 / 100
95 / 100
60 / 100
85 / 100

Manufacturability

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

Machinability

18 / 100
25 / 100
25 / 100
18 / 100

Polishability

55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

750 MJ/kg322,442 BTU/lb
400 MJ/kg171,969 BTU/lb
400 MJ/kg171,969 BTU/lb
500 MJ/kg214,962 BTU/lb

Embodied Carbon (primary production)

50 kg CO₂/kg
26 kg CO₂/kg
28 kg CO₂/kg
34 kg CO₂/kg

Embodied Water

700 L/kg83.9 gal/lb
700 L/kg83.9 gal/lb
600 L/kg71.9 gal/lb

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

2,105 kN·m/kg
2,006 kN·m/kg
2,722 kN·m/kg
3,033 kN·m/kg

Specific Stiffness (E / density)

282.7 MN·m/kg
130.7 MN·m/kg
127.8 MN·m/kg
162.4 MN·m/kg

Thermal Diffusivity

107.8 mm²/s
8 mm²/s
7 mm²/s
25.8 mm²/s

Thermal Shock Resistance Index

-1,049
-393
-527
-1,167

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

CapabilityM55JT300T700ST800H
Default condition
Relative cost$$$$ High$$$$ High$$$$ High$$$$ High
Min. machined wall
Best machined surface

Ready to make it?

Upload a CAD file and FabDigit prices the part in M55J and T300 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.