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Glass vs. Plastic PBT GF30 Compare Glass vs. Plastic PBT GF30 strength, stiffness, weight and thermal properties.
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Plastic PLA Plastic PETG Plastic ABS Plastic TPU Plastic Nylon Plastic ABS (bulk/injection) Plastic Polycarbonate Plastic POM/Acetal Plastic Nylon PA6 Plastic Nylon PA66 Plastic PEEK Plastic PTFE Plastic UHMWPE Plastic HDPE Plastic Polypropylene Plastic PMMA Plastic PBT GF30 Plastic PPS GF40 Plastic LCP GF30 Rubber Wood Aluminum Aluminum 6061-T6 Aluminum 7075-T6 Aluminum 2024-T351 Aluminum 5052-H32 Aluminum 7050-T7451 Aluminum A380 Aluminum 6063-T6 Aluminum 1100-O Aluminum ADC12 Steel Steel AISI 1018 Steel AISI 1045 Steel AISI 4340 Steel A992 Iron Titanium Titanium Ti-6Al-4V Stainless Steel 304 Stainless Steel 316 Stainless Steel 303 Stainless Steel 17-4PH Brass C360 Brass C260 Copper C110 Glass Nickel Inconel 718 Magnesium AZ31B-H24 Magnesium AZ91D Zinc Zamak 3 FDM ASA FDM Polycarbonate FDM PAHT-CF FDM HIPS SLA Resin Standard SLA Resin Tough 2000 SLA Resin Elastic 50A SLS PA12 Nylon DMLS AlSi10Mg Aluminum DMLS Ti-6Al-4V ELI Titanium DMLS 316L Stainless Steel DMLS 17-4PH Stainless Steel Concrete Brick Plywood Drywall PCB Laminate FR-4 Silicon Ceramic Alumina 96% Ceramic Aluminum Nitride Solder SAC305 Glass Natural Plastic PLA Plastic PETG Plastic ABS Plastic TPU Plastic Nylon Plastic ABS (bulk/injection) Plastic Polycarbonate Plastic POM/Acetal Plastic Nylon PA6 Plastic Nylon PA66 Plastic PEEK Plastic PTFE Plastic UHMWPE Plastic HDPE Plastic Polypropylene Plastic PMMA Plastic PBT GF30 Plastic PPS GF40 Plastic LCP GF30 Rubber Wood Aluminum Aluminum 6061-T6 Aluminum 7075-T6 Aluminum 2024-T351 Aluminum 5052-H32 Aluminum 7050-T7451 Aluminum A380 Aluminum 6063-T6 Aluminum 1100-O Aluminum ADC12 Steel Steel AISI 1018 Steel AISI 1045 Steel AISI 4340 Steel A992 Iron Titanium Titanium Ti-6Al-4V Stainless Steel 304 Stainless Steel 316 Stainless Steel 303 Stainless Steel 17-4PH Brass C360 Brass C260 Copper C110 Glass Nickel Inconel 718 Magnesium AZ31B-H24 Magnesium AZ91D Zinc Zamak 3 FDM ASA FDM Polycarbonate FDM PAHT-CF FDM HIPS SLA Resin Standard SLA Resin Tough 2000 SLA Resin Elastic 50A SLS PA12 Nylon DMLS AlSi10Mg Aluminum DMLS Ti-6Al-4V ELI Titanium DMLS 316L Stainless Steel DMLS 17-4PH Stainless Steel Concrete Brick Plywood Drywall PCB Laminate FR-4 Silicon Ceramic Alumina 96% Ceramic Aluminum Nitride Solder SAC305 Plastic PBT GF30 Bulk polymer (molded or machined) Try it on a partA sample part to run stress or thermal on, free in your browser Open in LessCAD Open in LessCAD Mechanical Yield strength not given (tensile used) not given (tensile used) Ultimate tensile strength 41 MPa source typical mean surface tensile stress at fracture (MOR), 60 s load, weathered, 50% breakage probability 140 MPa source stress at break, 23 °C Flexural strength 41 MPa source mean MOR (same value as tensile) 210 MPa source typical, 23 °C Elongation at break not sourced 3 % source strain at break, 23 °C Young's modulus (stiffness) 72 GPa source typical 9.8 GPa source typical, 23 °C Density 2,500 kg/m³ source typical 1,530 kg/m³ source typical 1.63x lighter Strength to weight 16.4 kN·m/kg 91.5 kN·m/kg 5.58x higher Stiffness to weight 28.8 MN·m/kg 4.5x higher 6.41 MN·m/kg Poisson's ratio 0.22 source typical not sourced Shear modulus 29.5 GPa not sourced Bulk modulus 42.9 GPa not sourced Speed of sound 5,367 m/s 2,531 m/s Thermal Thermal conductivity 0.937 W/m·K source typical at 75 F 0.27 W/m·K source typical (DIN 52612-1) Thermal expansion 8.3 µm/m·K source typical, 75-575 F 25 µm/m·K source longitudinal (flow), mean 23-55 °C 100 mm part over a 50 °C swing 41.5 µm growth 3.01x less 125 µm growth Specific heat 880 J/kg·K source typical at 75 F 1,050 J/kg·K source typical, 23 °C Heats up and cools (diffusivity) 0.426 mm²/s 2.53x faster 0.168 mm²/s Thermal shock resistance 50.1 W/m not sourced Melting point not sourced 223 °C source DSC (ISO 11357) Max service temperature 511 °C source strain point (ASTM C336) - stress-relaxation onset, not a rated service limit 205 °C source HDT 1.8 MPa Values for Annealed soda-lime-silica float glass, Pilkington North America Technical Bulletin ATS-129 (04/2025) 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.
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 Glass stronger than Plastic PBT GF30? Plastic PBT GF30 is stronger: its tensile strength is 140 MPa against 41 MPa for Glass (3.41x).
Which is lighter, Glass or Plastic PBT GF30? Plastic PBT GF30 is lighter: 1,530 kg/m³ against 2,500 kg/m³ for Glass.
Which is stiffer, Glass or Plastic PBT GF30? Glass is stiffer: Young's modulus 72 GPa against 9.8 GPa for Plastic PBT GF30, so the same part in Glass deflects less under the same load.
Which is lighter for the same job, Glass or Plastic PBT GF30? For the same stiffness or strength: Glass is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate; Plastic PBT GF30 is lighter for a strong rod or tie, strong beam, strong panel or plate.
Part that must be Glass Plastic PBT GF30 Stiff rod or tie (tension) lighter 4.5x heavier Stiff beam (bending) lighter 1.66x heavier Stiff panel or plate lighter 19% heavier Strong rod or tie 5.58x heavier lighter Strong beam 3.71x heavier lighter Strong panel or plate 3.02x heavier lighter
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, Glass or Plastic PBT GF30? Glass conducts heat better: 0.937 W/m·K against 0.27 W/m·K for Plastic PBT GF30.
Which expands less with temperature? Glass expands less: 8.3 µm/m·K against 25 µm/m·K for Plastic PBT GF30.
Among 72 materials 1k 10k 0.1 1 10 100 Density (kg/m³) Young's modulus (GPa) Plastic PLA Plastic PETG Plastic ABS Plastic TPU Plastic Nylon Aluminum Steel Iron Titanium Steel AISI 1018 Stainless Steel 304 Stainless Steel 316 Aluminum 6061-T6 Aluminum 7075-T6 Brass C360 Copper C110 Steel AISI 1045 Steel AISI 4340 Steel A992 Stainless Steel 303 Stainless Steel 17-4PH Aluminum 2024-T351 Aluminum 5052-H32 Aluminum 7050-T7451 Titanium Ti-6Al-4V Brass C260 Nickel Inconel 718 Magnesium AZ31B-H24 Zinc Zamak 3 Plastic ABS (bulk/injection) Plastic Polycarbonate Plastic POM/Acetal Plastic Nylon PA6 Plastic Nylon PA66 Plastic PEEK Plastic UHMWPE Plastic HDPE Plastic Polypropylene Plastic PMMA FDM ASA FDM Polycarbonate FDM PAHT-CF FDM HIPS SLA Resin Tough 2000 SLS PA12 Nylon DMLS AlSi10Mg Aluminum DMLS Ti-6Al-4V ELI Titanium DMLS 316L Stainless Steel DMLS 17-4PH Stainless Steel PCB Laminate FR-4 Silicon Ceramic Alumina 96% Ceramic Aluminum Nitride Aluminum A380 Aluminum 6063-T6 Aluminum 1100-O Aluminum ADC12 Magnesium AZ91D Solder SAC305 Plastic PPS GF40 Plastic LCP GF30 Glass Plastic PBT GF30 Stiffness against density 1k 10k 10 100 1k Density (kg/m³) Yield strength (MPa) Plastic PLA Plastic PETG Plastic ABS Plastic TPU Plastic Nylon Rubber Aluminum Steel Iron Titanium Steel AISI 1018 Stainless Steel 304 Stainless Steel 316 Aluminum 6061-T6 Aluminum 7075-T6 Brass C360 Copper C110 Steel AISI 1045 Steel AISI 4340 Steel A992 Stainless Steel 303 Stainless Steel 17-4PH Aluminum 2024-T351 Aluminum 5052-H32 Aluminum 7050-T7451 Titanium Ti-6Al-4V Brass C260 Nickel Inconel 718 Magnesium AZ31B-H24 Zinc Zamak 3 Plastic ABS (bulk/injection) Plastic Polycarbonate Plastic POM/Acetal Plastic Nylon PA6 Plastic Nylon PA66 Plastic PEEK Plastic PTFE Plastic UHMWPE Plastic HDPE Plastic Polypropylene Plastic PMMA FDM ASA FDM Polycarbonate FDM PAHT-CF FDM HIPS SLA Resin Tough 2000 SLA Resin Elastic 50A SLS PA12 Nylon DMLS AlSi10Mg Aluminum DMLS Ti-6Al-4V ELI Titanium DMLS 316L Stainless Steel DMLS 17-4PH Stainless Steel Brick PCB Laminate FR-4 Silicon Ceramic Alumina 96% Aluminum A380 Aluminum 6063-T6 Aluminum 1100-O Aluminum ADC12 Magnesium AZ91D Solder SAC305 Plastic PPS GF40 Plastic LCP GF30 Glass Plastic PBT GF30 Strength against density