FabDigit

Epoxy vs E-51 and 2 more: properties

EpoxyE-51E-44EPN

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

3 GPa0.44 Msi
3 GPa0.44 Msi
3.1 GPa0.45 Msi
3.3 GPa0.48 Msi

Shear Modulus

1.2 GPa0.17 Msi
1.1 GPa0.16 Msi
1.2 GPa0.17 Msi
1.3 GPa0.18 Msi

Bulk Modulus

5 GPa0.65 Msi
4 GPa0.51 Msi
4 GPa0.52 Msi
4 GPa0.61 Msi

Poisson's Ratio

0.35
0.35
0.35
0.36

Tensile Strength (Ultimate)

65 MPa9.4 ksi
65 MPa9.4 ksi
62 MPa9 ksi
72 MPa10.4 ksi

Elongation at Break

4%
4%
4.5%
2%

Compressive Strength

110 MPa16 ksi
110 MPa16 ksi
115 MPa16.7 ksi
155 MPa22.5 ksi

Compressive Modulus

3 GPa0.44 Msi
2.9 GPa0.42 Msi
2.9 GPa0.42 Msi
3.2 GPa0.46 Msi

Flexural Strength

110 MPa16 ksi
110 MPa16 ksi
100 MPa14.5 ksi
120 MPa17.4 ksi

Flexural Modulus

3 GPa0.44 Msi
3 GPa0.44 Msi
3 GPa0.44 Msi
3.4 GPa0.49 Msi

Shear Strength

45 MPa6.5 ksi
45 MPa6.5 ksi
20 MPa2.9 ksi
55 MPa8 ksi

Fracture Toughness (K_IC)

0.6 MPa·√m0.55 ksi·√in
0.65 MPa·√m0.59 ksi·√in
0.6 MPa·√m0.55 ksi·√in
0.55 MPa·√m0.5 ksi·√in

Izod Impact, Notched

20 J/m0.37 ft·lbf/in
25 J/m0.47 ft·lbf/in
25 J/m0.47 ft·lbf/in
18 J/m0.34 ft·lbf/in

Hardness, Shore D

85 Shore D
86 Shore D
85 Shore D
88 Shore D

Hardness, Rockwell M

100 HRM
100 HRM
100 HRM
108 HRM

Physical

Density and transition temperatures.

Density

1.2 g/cm³0.04 lb/in³
1.17 g/cm³0.04 lb/in³
1.18 g/cm³0.04 lb/in³
1.21 g/cm³0.04 lb/in³

Glass Transition (Tg)

120°C248 °F
95°C203 °F
105°C221 °F
175°C347 °F

Water Absorption (24 h)

0.15%
0.15%
0.2%
0.15%

Water Absorption (Saturation)

1.6%
1.6%
2%
1.6%

Refractive Index

1.56
1.56
1.57
1.59

Light Transmission

88%
88%

Thermal

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

Thermal Conductivity

0.2 W/m·K0.12 BTU/hr·ft·°F
0.19 W/m·K0.11 BTU/hr·ft·°F
0.19 W/m·K0.11 BTU/hr·ft·°F
0.2 W/m·K0.12 BTU/hr·ft·°F

Specific Heat Capacity

1,100 J/kg·K0.26 BTU/lb·°F
1,100 J/kg·K0.26 BTU/lb·°F
1,050 J/kg·K0.25 BTU/lb·°F
1,100 J/kg·K0.26 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

60 µm/m·K33.3 µin/in·°F
62 µm/m·K34.4 µin/in·°F
60 µm/m·K33.3 µin/in·°F
60 µm/m·K33.3 µin/in·°F

Max Service Temperature (continuous)

130°C266 °F
95°C203 °F
100°C212 °F
170°C338 °F

Min Service Temperature

-50°C-58 °F
-50°C-58 °F
-50°C-58 °F
-55°C-67 °F

Heat Deflection Temp. @ 0.45 MPa

130°C266 °F
110°C230 °F
115°C239 °F
190°C374 °F

Heat Deflection Temp. @ 1.8 MPa

110°C230 °F
88°C190 °F
95°C203 °F
168°C334 °F

Limiting Oxygen Index

20%
20%
20%
23%

Max Service Temperature (short-term)

180°C356 °F
150°C302 °F
140°C284 °F
220°C428 °F

Electrical

Conductivity and insulation.

Dielectric Strength

20 kV/mm508 V/mil
20 kV/mm508 V/mil
18 kV/mm457 V/mil
19 kV/mm483 V/mil

Dielectric Constant (1 MHz)

3.6
3.6
3.8
3.8

Surface Resistivity

1×10¹⁴ Ω
1×10¹⁴ Ω
1×10¹⁴ Ω
1×10¹⁵ Ω

Comparative Tracking Index (CTI)

300 V
250 V
350 V
250 V

Same in both: Electrical Resistivity 1×10¹³ Ω·m3.94×10²⁰ µΩ·in · Dissipation Factor (1 MHz) 0.02 · Volume Resistivity 1×10¹⁵ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

82 / 100
80 / 100
85 / 100
88 / 100

UV / Weathering Resistance

25 / 100
25 / 100
25 / 100
22 / 100

Manufacturability

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

Machinability

55 / 100
55 / 100
60 / 100
55 / 100

Weldability

0 / 100

Formability (cold)

5 / 100

Polishability

75 / 100
70 / 100
70 / 100
70 / 100

Mold Shrinkage

0.2%
0.3%
1.5%
1.2%

Mold Temperature (typ.)

165°C329 °F
80°C176 °F
80°C176 °F
165°C329 °F

Processing Melt Temperature (typ.)

100°C212 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

137 MJ/kg58,899 BTU/lb
137 MJ/kg58,899 BTU/lb
137 MJ/kg58,899 BTU/lb
135 MJ/kg58,040 BTU/lb

Embodied Carbon (primary production)

6.6 kg CO₂/kg
6.5 kg CO₂/kg
6.5 kg CO₂/kg
6.8 kg CO₂/kg

Embodied Water

190 L/kg22.8 gal/lb
250 L/kg30 gal/lb
250 L/kg30 gal/lb
250 L/kg30 gal/lb

Same in both: Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

54 kN·m/kg
56 kN·m/kg
53 kN·m/kg
60 kN·m/kg

Specific Stiffness (E / density)

2.5 MN·m/kg
2.6 MN·m/kg
2.6 MN·m/kg
2.7 MN·m/kg

Thermal Diffusivity

0.2 mm²/s
0.1 mm²/s
0.2 mm²/s
0.2 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 scale

Manufacturing and finishing

CapabilityEpoxyE-51E-44EPN
Default condition
Relative cost$$ Standard$$ Standard$$ Standard$$$ Premium
Min. machined wall
Best machined surface

Ready to make it?

Upload a CAD file and FabDigit prices the part in Epoxy and E-51 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.