ASA vs SMA
Polymer · grade comparison
ASA and SMA are both polymer grades. SMA is the stronger of the two: yield strength 50 MPa (7.25 ksi) against 45 MPa (6.53 ksi) for ASA, about 11% more; tensile strength follows at 50 MPa (7.25 ksi) vs 47 MPa (6.82 ksi). In exchange, ASA is the more ductile: elongation 25% versus 2.5% for SMA, and SMA is harder (85 Shore D vs 78 Shore D). SMA is stiffer (3.3 GPa vs 2.2 GPa) and SMA runs hotter in service (100°C vs 80°C continuous). On the shop floor, ASA machines more easily (very good vs good), ASA welds better (very good vs good), and ASA sits in a lower cost tier (standard, $$) than SMA (premium, $$$).
ASAChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
SMAChoose it when strength drives the design, or when the part sees heat.
ASA vs SMA: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all polymer grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Flexural Strength
Flexural Modulus
Shear Strength
Izod Impact, Notched
Hardness, Shore D
Hardness, Rockwell M
Hardness, Rockwell R
Compressive Modulus
Fracture Toughness (K_IC)
Physical
Density and transition temperatures.
Density
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Light Transmission
Same in both: Refractive Index 1.57
Thermal
How each material carries heat and how hot it can run.
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Vicat Softening Point (B50)
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Thermal Conductivity 0.17 W/m·K0.1 BTU/hr·ft·°F · Min Service Temperature -30°C-22 °F
Electrical
Conductivity and insulation.
Dielectric Strength
Dielectric Constant (1 MHz)
Dissipation Factor (1 MHz)
Same in both: Electrical Resistivity 1×10¹⁴ Ω·m3.94×10²¹ µΩ·in · Volume Resistivity 1×10¹⁶ Ω·cm · Surface Resistivity 1×10¹⁵ Ω · Comparative Tracking Index (CTI) 600 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
UV / Weathering Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Melt Flow Rate
Mold Temperature (typ.)
Same in both: Mold Shrinkage 0.5% · Processing Melt Temperature (typ.) 245°C473 °F
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Same in both: Thermal Diffusivity 0.1 mm²/s · 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.
Manufacturing and finishing
| Capability | ASA | SMA |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Injection molding | Yes | — |
| 3D printing | Yes | — |
| Default condition | Unfilled | — |
| Relative cost | $$ Standard | $$$ Premium |
| Min. machined wall | 0.5 mm | — |
| Best machined surface | Ra 0.8 µm | — |
| Chrome Plating (Plastic) | Yes | — |
| Conductive Coating | Yes | — |
| Dyeing (Nylon) | Yes | — |
| EMI Shielding Coating | Yes | — |
| Painting | Yes | — |
| Primer Coating | Yes | — |
| Soft Touch Coating | Yes | — |
| Spray Painting | Yes | — |
| Tinted Coating | Yes | — |
| UV Coating | Yes | — |
| Vacuum Metallization | Yes | — |
| Waterproof Coating | Yes | — |
ASA vs SMA — frequently asked
Is SMA stronger than ASA?
Yes. SMA has a typical yield strength of 50 MPa (7.25 ksi) against 45 MPa (6.53 ksi) for ASA — about 11% more. Tensile strength is 50 MPa (7.25 ksi) vs 47 MPa (6.82 ksi).
Which is cheaper, ASA or SMA?
ASA is the lower-cost material: it sits in the standard tier ($$) while SMA is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, ASA or SMA?
ASA. Its machinability rates very good (75/100) against good (55/100) for SMA; for welding the order is ASA first (very good, 70/100) then SMA (good, 55/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in ASA and SMA 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.