FabDigitFabDigit

PC-ABS vs SBS

Polymer · grade comparison

PC-ABS and SBS are both polymer grades. PC-ABS is the stronger of the two: tensile strength 56 MPa (8.12 ksi) against 30 MPa (4.35 ksi) for SBS, about 87% more. In exchange, SBS is the more ductile: elongation 880% versus 90% for PC-ABS, and PC-ABS is harder (79 Shore D vs 22 Shore D). SBS is lighter (0.94 g/cm³ vs 1.15 g/cm³ for PC-ABS) and PC-ABS is stiffer (2.4 GPa vs 0.02 GPa). On the shop floor, PC-ABS machines more easily (good vs poor) and PC-ABS welds better (very good vs good).

PC-ABSChoose it when strength drives the design, or when the part sees heat.

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

PC-ABS vs SBS: properties

PC-ABSSBS

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

2.4 GPa0.35 Msi
0.02 GPa0 Msi

Shear Modulus

0.87 GPa0.13 Msi
0.01 GPa7.25×10⁻⁴ Msi

Bulk Modulus

4 GPa0.52 Msi
2 GPa0.29 Msi

Poisson's Ratio

0.39
0.49

Tensile Strength (Ultimate)

56 MPa8.1 ksi
30 MPa4.4 ksi

Yield Strength (0.2% offset)

55 MPa8 ksi
—

Elongation at Break

90%
880%

Compressive Strength

65 MPa9.4 ksi
—

Compressive Modulus

2.3 GPa0.33 Msi
—

Flexural Strength

85 MPa12.3 ksi
—

Flexural Modulus

2.3 GPa0.33 Msi
—

Shear Strength

40 MPa5.8 ksi
—

Fracture Toughness (K_IC)

3.5 MPa·√m3.2 ksi·√in
—

Izod Impact, Notched

500 J/m9.4 ft·lbf/in
—

Hardness, Shore D

79 Shore D
22 Shore D

Hardness, Rockwell M

68 HRM
—

Hardness, Rockwell R

115 HRR
—

Hardness, Shore A

—
71 Shore A

Tear Strength

—
45 kN/m257 lbf/in

Compression Set (22 h, 70 °C)

—
40%

Physical

Density and transition temperatures.

Density

1.15 g/cm³0.04 lb/in³
0.94 g/cm³0.03 lb/in³

Glass Transition (Tg)

125°C257 °F
-90°C-130 °F

Water Absorption (24 h)

0.2%
0.06%

Water Absorption (Saturation)

0.6%
—

Refractive Index

—
1.54

Thermal

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

Thermal Conductivity

0.2 W/m·K0.12 BTU/hr·ft·°F
0.17 W/m·K0.1 BTU/hr·ft·°F

Specific Heat Capacity

1,400 J/kg·K0.33 BTU/lb·°F
1,900 J/kg·K0.45 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

75 µm/m·K41.7 µin/in·°F
170 µm/m·K94.4 µin/in·°F

Max Service Temperature (continuous)

100°C212 °F
65°C149 °F

Min Service Temperature

-40°C-40 °F
-60°C-76 °F

Heat Deflection Temp. @ 0.45 MPa

120°C248 °F
—

Heat Deflection Temp. @ 1.8 MPa

105°C221 °F
—

Vicat Softening Point (B50)

135°C275 °F
—

Limiting Oxygen Index

23%
19%

Max Service Temperature (short-term)

125°C257 °F
85°C185 °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

25 kV/mm635 V/mil
22 kV/mm559 V/mil

Dielectric Constant (1 MHz)

3
2.4

Dissipation Factor (1 MHz)

0.008
8×10⁻⁴

Volume Resistivity

1×10¹⁶ Ω·cm
1×10¹⁵ Ω·cm

Surface Resistivity

1×10¹⁵ Ω
1×10¹⁴ Ω

Comparative Tracking Index (CTI)

250 V
—

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

78 / 100
80 / 100

UV / Weathering Resistance

30 / 100
20 / 100

Manufacturability

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

Machinability

65 / 100
20 / 100

Weldability

72 / 100
60 / 100

Formability (cold)

60 / 100
90 / 100

Polishability

65 / 100
30 / 100

Mold Shrinkage

0.6%
1.6%

Melt Flow Rate

14 g/10 min
0.5 g/10 min

Processing Melt Temperature (typ.)

265°C509 °F
185°C365 °F

Mold Temperature (typ.)

75°C167 °F
30°C86 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

100 MJ/kg42,992 BTU/lb
102 MJ/kg43,852 BTU/lb

Embodied Carbon (primary production)

4.6 kg CO₂/kg
3.8 kg CO₂/kg

Typical Recycled Content

15%
0%

Same in both: Embodied Water 200 L/kg24 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

49 kN·m/kg
32 kN·m/kg

Specific Stiffness (E / density)

2.1 MN·m/kg
0 MN·m/kg

Thermal Shock Resistance Index

0
2

Same in both: Thermal Diffusivity 0.1 mm²/s

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 scalePC-ABS

Manufacturing and finishing

CapabilityPC-ABSSBS
CNC machiningYes—
Sheet metalYes—
Injection moldingYes—
Default conditionUnfilled—
Relative cost$$ Standard$$ Standard
Min. machined wall0.5 mm—
Best machined surfaceRa 0.8 µm—
Chrome Plating (Plastic)Yes—
EMI Shielding CoatingYes—
PaintingYes—
Soft Touch CoatingYes—
Spray PaintingYes—
UV CoatingYes—

PC-ABS vs SBS — frequently asked

Is PC-ABS stronger than SBS?

Yes. PC-ABS has a typical tensile strength of 56 MPa (8.12 ksi) against 30 MPa (4.35 ksi) for SBS — about 87% more.

Which is cheaper, PC-ABS or SBS?

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

Which is easier to machine, PC-ABS or SBS?

PC-ABS. Its machinability rates good (65/100) against poor (20/100) for SBS; for welding the order is PC-ABS first (very good, 72/100) then SBS (good, 60/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in PC-ABS and SBS 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.