Materials / Compare
Plastic PBT GF30 vs. Plastic Polycarbonate
Compare Plastic PBT GF30 vs. Plastic Polycarbonate strength, stiffness, weight and thermal properties.
| Try it on a partA bracket to run stress or thermal on, free in your browser | Open in LessCAD | Open in LessCAD |
|---|---|---|
| Mechanical | ||
| Yield strength | not given (tensile used) | 65MPasourcetypical, tensile yield |
| Ultimate tensile strength | 140MPasourcestress at break, 23 °C | 65MPasourcetypical, stress at break |
| Flexural strength | 210MPasourcetypical, 23 °C | 97MPasourcetypical, flexural strength |
| Elongation at break | 3%sourcestrain at break, 23 °C | 125%sourcetypical, strain at break |
| Young's modulus (stiffness) | 9.8GPasourcetypical, 23 °C | 2.4GPasourcetypical |
| Density | 1,530kg/m³sourcetypical | 1,200kg/m³sourcetypical27% lighter |
| Strength to weight | 91.5kN·m/kg1.69x higher | 54.2kN·m/kg |
| Stiffness to weight | 6.41MN·m/kg3.2x higher | 2MN·m/kg |
| Poisson's ratio | not sourced | 0.38sourcetypical, polycarbonate family (Covestro Part and Mold Design guide, Table 3-1) |
| Shear modulus | not sourced | 0.87GPa |
| Bulk modulus | not sourced | 3.33GPa |
| Speed of sound | 2,531m/s | 1,414m/s |
| Thermal | ||
| Thermal conductivity | 0.27W/m·Ksourcetypical (DIN 52612-1) | 0.2W/m·Ksourcetypical, through-plane, 23 C |
| Thermal expansion | 25µm/m·Ksourcelongitudinal (flow), mean 23-55 °C | 65µm/m·Ksourcetypical, 23-55 C, parallel and normal |
| 100 mm part over a 50 °C swing | 125µm growth2.6x less | 325µm growth |
| Specific heat | 1,050J/kg·Ksourcetypical, 23 °C | 1,172J/kg·Ksourcetypical (guide value), Bayer ASTM datasheet for Makrolon 2405, ASTM D 2766 |
| Heats up and cools (diffusivity) | 0.168mm²/s18% faster | 0.142mm²/s |
| Thermal shock resistance | not sourced | 51.7W/m |
| Melting point | 223°CsourceDSC (ISO 11357) | not sourced |
| Glass transition | not sourced | 144°Csourcetypical, DSC 10 C/min |
| Max service temperature | 205°CsourceHDT 1.8 MPa | 125°CsourceUL 746B RTI, tensile strength, 1.5 mm |
| Values for | BASF Ultradur B 4300 G6 (PBT, 30% glass fibre), injection moulding grade; product information sheet 09/2026, typical values for uncoloured product at 23 °C. | Covestro Makrolon 2405 general-purpose PC (MVR 19), Covestro technical datasheet version 2026-09-28, typical values |
Every value links to the document that states it. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.
Questions
Is Plastic PBT GF30 stronger than Plastic Polycarbonate?
Plastic PBT GF30 is stronger: its tensile strength is 140 MPa against yield strength 65 MPa for Plastic Polycarbonate (2.15x).
Which is lighter, Plastic PBT GF30 or Plastic Polycarbonate?
Plastic Polycarbonate is lighter: 1,200 kg/m³ against 1,530 kg/m³ for Plastic PBT GF30.
Which is stiffer, Plastic PBT GF30 or Plastic Polycarbonate?
Plastic PBT GF30 is stiffer: Young's modulus 9.8 GPa against 2.4 GPa for Plastic Polycarbonate, so the same part in Plastic PBT GF30 deflects less under the same load.
Which is lighter for the same job, Plastic PBT GF30 or Plastic Polycarbonate?
For the same stiffness or strength: Plastic PBT GF30 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.
| Part that must be | Plastic PBT GF30 | Plastic Polycarbonate |
|---|---|---|
| Stiff rod or tie (tension) | lighter | 3.2x heavier |
| Stiff beam (bending) | lighter | 1.58x heavier |
| Stiff panel or plate | lighter | 25% heavier |
| Strong rod or tie | lighter | 1.69x heavier |
| Strong beam | lighter | 31% heavier |
| Strong panel or plate | lighter | 15% heavier |
For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).
Which conducts heat better, Plastic PBT GF30 or Plastic Polycarbonate?
Plastic PBT GF30 conducts heat better: 0.27 W/m·K against 0.2 W/m·K for Plastic Polycarbonate.
Which expands less with temperature?
Plastic PBT GF30 expands less: 25 µm/m·K against 65 µm/m·K for Plastic Polycarbonate.