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HDPE vs PVC

Polymer · grade comparison

HDPE and PVC are both polymer grades, both corrosion resistant plastic. PVC is the stronger of the two: yield strength 50 MPa (7.25 ksi) against 26 MPa (3.77 ksi) for HDPE, about 92% more; tensile strength follows at 52 MPa (7.54 ksi) vs 28 MPa (4.06 ksi). In exchange, HDPE is the more ductile: elongation 600% versus 45% for PVC, and PVC is harder (82 Shore D vs 65 Shore D). HDPE is lighter (0.96 g/cm³ vs 1.42 g/cm³ for PVC) and PVC is stiffer (3 GPa vs 1.1 GPa). On the shop floor, PVC machines more easily (excellent vs very good).

HDPEChoose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

PVCChoose it when strength drives the design, or when the part is machined in volume.

HDPE vs PVC: properties

HDPEPVC

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

1.1 GPa0.16 Msi
3 GPa0.44 Msi

Shear Modulus

0.4 GPa0.06 Msi
1.1 GPa0.16 Msi

Bulk Modulus

3 GPa0.44 Msi
4 GPa0.61 Msi

Poisson's Ratio

0.44
0.38

Tensile Strength (Ultimate)

28 MPa4.1 ksi
52 MPa7.5 ksi

Yield Strength (0.2% offset)

26 MPa3.8 ksi
50 MPa7.3 ksi

Elongation at Break

600%
45%

Compressive Strength

22 MPa3.2 ksi
68 MPa9.9 ksi

Compressive Modulus

0.9 GPa0.13 Msi
2.9 GPa0.42 Msi

Flexural Strength

27 MPa3.9 ksi
90 MPa13.1 ksi

Flexural Modulus

1.2 GPa0.17 Msi
3 GPa0.44 Msi

Shear Strength

20 MPa2.9 ksi
41 MPa5.9 ksi

Fracture Toughness (K_IC)

2 MPa·√m1.8 ksi·√in
2.5 MPa·√m2.3 ksi·√in

Izod Impact, Notched

90 J/m1.7 ft·lbf/in
55 J/m1 ft·lbf/in

Hardness, Shore D

65 Shore D
82 Shore D

Hardness, Rockwell R

55 HRR
110 HRR

Physical

Density and transition temperatures.

Density

0.96 g/cm³0.03 lb/in³
1.42 g/cm³0.05 lb/in³

Melting Temperature (Tm)

132°C270 °F
—

Glass Transition (Tg)

-110°C-166 °F
80°C176 °F

Water Absorption (24 h)

0.01%
0.06%

Water Absorption (Saturation)

0.05%
0.2%

Same in both: Refractive Index 1.54

Thermal

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

Thermal Conductivity

0.48 W/m·K0.28 BTU/hr·ft·°F
0.16 W/m·K0.09 BTU/hr·ft·°F

Specific Heat Capacity

1,900 J/kg·K0.45 BTU/lb·°F
950 J/kg·K0.23 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

150 µm/m·K83.3 µin/in·°F
65 µm/m·K36.1 µin/in·°F

Max Service Temperature (continuous)

80°C176 °F
60°C140 °F

Min Service Temperature

-80°C-112 °F
-10°C14 °F

Heat Deflection Temp. @ 0.45 MPa

76°C169 °F
75°C167 °F

Heat Deflection Temp. @ 1.8 MPa

47°C117 °F
68°C154 °F

Vicat Softening Point (B50)

76°C169 °F
80°C176 °F

Limiting Oxygen Index

18%
45%

Max Service Temperature (short-term)

110°C230 °F
80°C176 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

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

Dielectric Strength

24 kV/mm610 V/mil
22 kV/mm559 V/mil

Dielectric Constant (1 MHz)

2.35
3.1

Dissipation Factor (1 MHz)

3×10⁻⁴
0.015

Volume Resistivity

1×10¹⁶ Ω·cm
1×10¹⁵ Ω·cm

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁴ Ω

Same in both: Comparative Tracking Index (CTI) 600 V

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

UV / Weathering Resistance

25 / 100
55 / 100

Same in both: Corrosion Resistance 90 / 100

Manufacturability

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

Machinability

75 / 100
85 / 100

Weldability

95 / 100
90 / 100

Formability (cold)

70 / 100
80 / 100

Polishability

30 / 100
60 / 100

Mold Shrinkage

2%
0.4%

Melt Flow Rate

8 g/10 min
—

Processing Melt Temperature (typ.)

230°C446 °F
185°C365 °F

Same in both: Mold Temperature (typ.) 40°C104 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

78 MJ/kg33,534 BTU/lb
67 MJ/kg28,805 BTU/lb

Embodied Carbon (primary production)

2 kg CO₂/kg
2.4 kg CO₂/kg

Embodied Water

90 L/kg10.8 gal/lb
120 L/kg14.4 gal/lb

Same in both: Typical Recycled Content 10%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

29 kN·m/kg
37 kN·m/kg

Specific Stiffness (E / density)

1.2 MN·m/kg
2.1 MN·m/kg

Modulus of Resilience

307 kJ/m³
417 kJ/m³

Thermal Diffusivity

0.3 mm²/s
0.1 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 scaleHDPEPVC

Manufacturing and finishing

CapabilityHDPEPVC
Default conditionFDA CompliantRigid (Type I)
Relative cost$ Budget$ Budget
Min. machined wall0.5 mm0.5 mm
Best machined surfaceRa 0.8 µmRa 0.8 µm

Both are offered for CNC machining, Sheet metal and Injection molding. Both take the same 6 finishes: Chrome Plating (Plastic), EMI Shielding Coating, Painting, Soft Touch Coating, Spray Painting, UV Coating.

HDPE vs PVC — frequently asked

Is PVC stronger than HDPE?

Yes. PVC has a typical yield strength of 50 MPa (7.25 ksi) against 26 MPa (3.77 ksi) for HDPE — about 92% more. Tensile strength is 52 MPa (7.54 ksi) vs 28 MPa (4.06 ksi).

Which is cheaper, HDPE or PVC?

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

Which is easier to machine, HDPE or PVC?

PVC. Its machinability rates excellent (85/100) against very good (75/100) for HDPE; for welding the order is HDPE first (excellent, 95/100) then PVC (excellent, 90/100).

Ready to make it?

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