FabDigit

HDPE vs LDPE and 2 more: properties

HDPELDPEUHMW-PEHMWPE

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

1.1 GPa0.16 Msi
0.22 GPa0.03 Msi
0.72 GPa0.1 Msi
0.95 GPa0.14 Msi

Shear Modulus

0.4 GPa0.06 Msi
0.08 GPa0.01 Msi
0.25 GPa0.04 Msi
0.35 GPa0.05 Msi

Bulk Modulus

3 GPa0.44 Msi
2 GPa0.26 Msi
3 GPa0.38 Msi

Poisson's Ratio

0.44
0.45
0.46
0.44

Tensile Strength (Ultimate)

28 MPa4.1 ksi
11 MPa1.6 ksi
40 MPa5.8 ksi
30 MPa4.4 ksi

Yield Strength (0.2% offset)

26 MPa3.8 ksi
10 MPa1.5 ksi
21 MPa3 ksi
24 MPa3.5 ksi

Elongation at Break

600%
450%
350%
700%

Compressive Strength

22 MPa3.2 ksi
9 MPa1.3 ksi
20 MPa2.9 ksi
22 MPa3.2 ksi

Compressive Modulus

0.9 GPa0.13 Msi
0.2 GPa0.03 Msi
0.6 GPa0.09 Msi
0.9 GPa0.13 Msi

Flexural Strength

27 MPa3.9 ksi
10 MPa1.5 ksi
25 MPa3.6 ksi
26 MPa3.8 ksi

Flexural Modulus

1.2 GPa0.17 Msi
0.25 GPa0.04 Msi
0.75 GPa0.11 Msi
1.1 GPa0.15 Msi

Shear Strength

20 MPa2.9 ksi
8 MPa1.2 ksi
22 MPa3.2 ksi
20 MPa2.9 ksi

Fracture Toughness (K_IC)

2 MPa·√m1.8 ksi·√in
1.4 MPa·√m1.3 ksi·√in
3.5 MPa·√m3.2 ksi·√in
2.8 MPa·√m2.5 ksi·√in

Izod Impact, Notched

90 J/m1.7 ft·lbf/in
800 J/m15 ft·lbf/in
1,300 J/m24.3 ft·lbf/in
250 J/m4.7 ft·lbf/in

Hardness, Shore D

65 Shore D
47 Shore D
64 Shore D
65 Shore D

Hardness, Rockwell R

55 HRR
50 HRR
50 HRR

Hardness, Shore A

93 Shore A

Tear Strength

55 kN/m314 lbf/in

Physical

Density and transition temperatures.

Density

0.96 g/cm³0.03 lb/in³
0.92 g/cm³0.03 lb/in³
0.94 g/cm³0.03 lb/in³
0.95 g/cm³0.03 lb/in³

Melting Temperature (Tm)

132°C270 °F
110°C230 °F
135°C275 °F
133°C271 °F

Glass Transition (Tg)

-110°C-166 °F
-110°C-166 °F
-120°C-184 °F
-120°C-184 °F

Water Absorption (Saturation)

0.05%
0.02%
0.01%
0.02%

Refractive Index

1.54
1.51
1.51
1.54

Light Transmission

80%

Same in both: Water Absorption (24 h) 0.01%

Thermal

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

Thermal Conductivity

0.48 W/m·K0.28 BTU/hr·ft·°F
0.33 W/m·K0.19 BTU/hr·ft·°F
0.41 W/m·K0.24 BTU/hr·ft·°F
0.45 W/m·K0.26 BTU/hr·ft·°F

Specific Heat Capacity

1,900 J/kg·K0.45 BTU/lb·°F
2,100 J/kg·K0.5 BTU/lb·°F
1,840 J/kg·K0.44 BTU/lb·°F
1,900 J/kg·K0.45 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

150 µm/m·K83.3 µin/in·°F
190 µm/m·K106 µin/in·°F
200 µm/m·K111 µin/in·°F
160 µm/m·K88.9 µin/in·°F

Max Service Temperature (continuous)

80°C176 °F
70°C158 °F
80°C176 °F
80°C176 °F

Min Service Temperature

-80°C-112 °F
-60°C-76 °F
-200°C-328 °F
-100°C-148 °F

Heat Deflection Temp. @ 0.45 MPa

76°C169 °F
47°C117 °F
80°C176 °F
77°C171 °F

Heat Deflection Temp. @ 1.8 MPa

47°C117 °F
34°C93 °F
44°C111 °F
46°C115 °F

Vicat Softening Point (B50)

76°C169 °F
50°C122 °F
80°C176 °F
125°C257 °F

Limiting Oxygen Index

18%
18%
17%
17%

Max Service Temperature (short-term)

110°C230 °F
90°C194 °F
110°C230 °F
110°C230 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in
1×10¹³ Ω·m3.94×10²⁰ µΩ·in
1×10¹⁴ Ω·m3.94×10²¹ µΩ·in

Dielectric Strength

24 kV/mm610 V/mil
25 kV/mm635 V/mil
30 kV/mm762 V/mil
24 kV/mm610 V/mil

Dielectric Constant (1 MHz)

2.35
2.28
2.3
2.3

Volume Resistivity

1×10¹⁶ Ω·cm
1×10¹⁶ Ω·cm
1×10¹⁵ Ω·cm
1×10¹⁶ Ω·cm

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁵ Ω
1×10¹⁴ Ω
1×10¹⁵ Ω

Same in both: Dissipation Factor (1 MHz) 3×10⁻⁴ · Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

90 / 100
88 / 100
90 / 100
93 / 100

UV / Weathering Resistance

25 / 100
20 / 100
30 / 100
25 / 100

Manufacturability

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

Machinability

75 / 100
45 / 100
75 / 100
62 / 100

Weldability

95 / 100
95 / 100
15 / 100
92 / 100

Formability (cold)

70 / 100
90 / 100
55 / 100
78 / 100

Polishability

30 / 100
30 / 100
25 / 100
25 / 100

Mold Shrinkage

2%
2.5%
3%
2.5%

Melt Flow Rate

8 g/10 min
2 g/10 min
0.1 g/10 min

Processing Melt Temperature (typ.)

230°C446 °F
190°C374 °F
200°C392 °F
215°C419 °F

Mold Temperature (typ.)

40°C104 °F
30°C86 °F
35°C95 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

78 MJ/kg33,534 BTU/lb
80 MJ/kg34,394 BTU/lb
85 MJ/kg36,543 BTU/lb
78 MJ/kg33,534 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
2.1 kg CO₂/kg
3.2 kg CO₂/kg
2.1 kg CO₂/kg

Embodied Water

90 L/kg10.8 gal/lb
120 L/kg14.4 gal/lb
100 L/kg12 gal/lb
110 L/kg13.2 gal/lb

Typical Recycled Content

10%
10%
0%
10%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

29 kN·m/kg
12 kN·m/kg
43 kN·m/kg
32 kN·m/kg

Specific Stiffness (E / density)

1.2 MN·m/kg
0.2 MN·m/kg
0.8 MN·m/kg
1 MN·m/kg

Modulus of Resilience

307 kJ/m³
227 kJ/m³
306 kJ/m³
303 kJ/m³

Thermal Diffusivity

0.3 mm²/s
0.2 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 scaleHDPELDPEUHMW-PEHMWPE

Manufacturing and finishing

CapabilityHDPELDPEUHMW-PEHMWPE
CNC machiningYesYes
Sheet metalYesYesYes
Injection moldingYesYesYes
Default conditionFDA CompliantUnfilledFDA
Relative cost$ Budget$ Budget$$ Standard$ Budget
Min. machined wall0.5 mm0.5 mm
Best machined surfaceRa 0.8 µmRa 0.8 µm
Chrome Plating (Plastic)YesYesYes
EMI Shielding CoatingYesYesYes
PaintingYesYesYes
Soft Touch CoatingYesYesYes
Spray PaintingYesYesYes
UV CoatingYesYesYes

Ready to make it?

Upload a CAD file and FabDigit prices the part in HDPE and LDPE 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.