BMC vs SMC
Polymer · grade comparison
BMC and SMC are both polymer grades. SMC is the stronger of the two: tensile strength 75 MPa (10.9 ksi) against 42 MPa (6.09 ksi) for BMC, about 79% more. SMC is the more ductile: elongation 1.5% versus 0.5% for BMC. BMC runs hotter in service (150°C vs 130°C continuous) and BMC conducts heat better (0.6 W/m·K vs 0.25 W/m·K).
BMCChoose it when the part sees heat.
SMCChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
BMC vs SMC: 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.
Tensile Strength (Ultimate)
Elongation at Break
Compressive Strength
Compressive Modulus
Flexural Strength
Flexural Modulus
Shear Strength
Izod Impact, Notched
Same in both: Elastic (Young's) Modulus 11 GPa1.6 Msi · Shear Modulus 4.2 GPa0.61 Msi · Poisson's Ratio 0.3 · Hardness, Rockwell M 100 HRM
Physical
Density and transition temperatures.
Glass Transition (Tg)
Water Absorption (24 h)
Water Absorption (Saturation)
Same in both: Density 1.85 g/cm³0.07 lb/in³
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Max Service Temperature (continuous)
Heat Deflection Temp. @ 0.45 MPa
Heat Deflection Temp. @ 1.8 MPa
Limiting Oxygen Index
Max Service Temperature (short-term)
Same in both: Thermal Expansion (CTE, 20–100 °C) 25 µm/m·K13.9 µin/in·°F · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Dielectric Strength
Dielectric Constant (1 MHz)
Volume Resistivity
Same in both: Dissipation Factor (1 MHz) 0.02 · Surface Resistivity 1×10¹³ Ω · Comparative Tracking Index (CTI) 600 V
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
UV / Weathering Resistance
Same in both: Corrosion Resistance 70 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Polishability
Mold Shrinkage
Processing Melt Temperature (typ.)
Mold Temperature (typ.)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 0%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Thermal Diffusivity
Same in both: Specific Stiffness (E / density) 5.9 MN·m/kg · 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 | BMC | SMC |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | — |
| Best machined surface | — | — |
BMC vs SMC — frequently asked
Is SMC stronger than BMC?
Yes. SMC has a typical tensile strength of 75 MPa (10.9 ksi) against 42 MPa (6.09 ksi) for BMC — about 79% more.
Which is cheaper, BMC or SMC?
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, BMC or SMC?
BMC. Its machinability rates fair (35/100) against poor (30/100) for SMC.
Ready to make it?
Upload a CAD file and FabDigit prices the part in BMC and SMC 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.