FabDigitFabDigit

ASA vs SEBS

Polymer · grade comparison

ASA and SEBS are both polymer grades. ASA is the stronger of the two: tensile strength 47 MPa (6.82 ksi) against 30 MPa (4.35 ksi) for SEBS, about 57% more. In exchange, SEBS is the more ductile: elongation 550% versus 25% for ASA, and ASA is harder (78 Shore D vs 24 Shore D). SEBS is lighter (0.91 g/cm³ vs 1.07 g/cm³ for ASA) and ASA is stiffer (2.2 GPa vs 0.02 GPa). On the shop floor, ASA machines more easily (very good vs poor) and ASA welds better (very good vs good).

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

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

ASA vs SEBS: properties

ASASEBS

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

2.2 GPa0.32 Msi
0.02 GPa0 Msi

Shear Modulus

0.8 GPa0.12 Msi
—

Bulk Modulus

4 GPa0.51 Msi
—

Poisson's Ratio

0.37
0.48

Tensile Strength (Ultimate)

47 MPa6.8 ksi
30 MPa4.4 ksi

Yield Strength (0.2% offset)

45 MPa6.5 ksi
—

Elongation at Break

25%
550%

Compressive Strength

62 MPa9 ksi
—

Flexural Strength

72 MPa10.4 ksi
—

Flexural Modulus

2.2 GPa0.32 Msi
—

Shear Strength

35 MPa5.1 ksi
—

Izod Impact, Notched

130 J/m2.4 ft·lbf/in
—

Hardness, Shore D

78 Shore D
24 Shore D

Hardness, Rockwell M

70 HRM
—

Hardness, Rockwell R

105 HRR
—

Hardness, Shore A

—
72 Shore A

Tear Strength

—
45 kN/m257 lbf/in

Compression Set (22 h, 70 °C)

—
45%

Physical

Density and transition temperatures.

Density

1.07 g/cm³0.04 lb/in³
0.91 g/cm³0.03 lb/in³

Glass Transition (Tg)

105°C221 °F
-55°C-67 °F

Water Absorption (24 h)

0.3%
0.05%

Water Absorption (Saturation)

1%
0.15%

Refractive Index

1.57
1.505

Thermal

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

Thermal Conductivity

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

Specific Heat Capacity

1,450 J/kg·K0.35 BTU/lb·°F
1,900 J/kg·K0.45 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

85 µm/m·K47.2 µin/in·°F
180 µm/m·K100 µin/in·°F

Max Service Temperature (continuous)

80°C176 °F
85°C185 °F

Min Service Temperature

-30°C-22 °F
-60°C-76 °F

Heat Deflection Temp. @ 0.45 MPa

98°C208 °F
—

Heat Deflection Temp. @ 1.8 MPa

88°C190 °F
—

Vicat Softening Point (B50)

100°C212 °F
75°C167 °F

Limiting Oxygen Index

19%
19%

Max Service Temperature (short-term)

95°C203 °F
110°C230 °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
2.3

Dissipation Factor (1 MHz)

0.015
5×10⁻⁴

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).

Corrosion Resistance

70 / 100
80 / 100

UV / Weathering Resistance

88 / 100
80 / 100

Manufacturability

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

Machinability

75 / 100
25 / 100

Weldability

70 / 100
55 / 100

Formability (cold)

75 / 100
90 / 100

Polishability

70 / 100
30 / 100

Mold Shrinkage

0.5%
1.8%

Melt Flow Rate

12 g/10 min
5 g/10 min

Processing Melt Temperature (typ.)

245°C473 °F
210°C410 °F

Mold Temperature (typ.)

65°C149 °F
30°C86 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

96 MJ/kg41,273 BTU/lb
105 MJ/kg45,142 BTU/lb

Embodied Carbon (primary production)

3.9 kg CO₂/kg
3.6 kg CO₂/kg

Embodied Water

200 L/kg24 gal/lb
180 L/kg21.6 gal/lb

Typical Recycled Content

5%
2%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

44 kN·m/kg
33 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 scaleASA

Manufacturing and finishing

CapabilityASASEBS
CNC machiningYes—
Sheet metalYes—
Injection moldingYes—
3D printingYes—
Default conditionUnfilled—
Relative cost$$ Standard$$ Standard
Min. machined wall0.5 mm—
Best machined surfaceRa 0.8 µm—
Chrome Plating (Plastic)Yes—
Conductive CoatingYes—
Dyeing (Nylon)Yes—
EMI Shielding CoatingYes—
PaintingYes—
Primer CoatingYes—
Soft Touch CoatingYes—
Spray PaintingYes—
Tinted CoatingYes—
UV CoatingYes—
Vacuum MetallizationYes—
Waterproof CoatingYes—

ASA vs SEBS — frequently asked

Is ASA stronger than SEBS?

Yes. ASA has a typical tensile strength of 47 MPa (6.82 ksi) against 30 MPa (4.35 ksi) for SEBS — about 57% more.

Which is cheaper, ASA or SEBS?

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, ASA or SEBS?

ASA. Its machinability rates very good (75/100) against poor (25/100) for SEBS; for welding the order is ASA first (very good, 70/100) then SEBS (good, 55/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in ASA and SEBS 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.