Torlon® 4203 (Polyamide-imide)


Torlon® 4203 polyamide-imide offers excellent compressive strength and the highest elongation of the Torlon grades.  Several manufacturers offer bearing grade versions by the tradenames Duratron® PAI, and Tecator®. It provides electrical insulation and exceptional impact strength.  Torlon® 4203 is commonly used for electrical connectors and insulators due to its high dielectric strength.  It is also an excellent choice for bearing and wear applications involving impact loading and abrasive environments.  Its ability to carry high loads over a broad temperature range makes it ideal for structural components such as linkage bearings and seal rings.

Specification Test Value Units
Specific Gravity, 73°F D792  1.41
Tensile Strength @ Yield, 73°F D638  20,000 psi
Tensile Modulus of Elasticity, 73°F D638  600,000 psi
Tensile Elongation (at break), 73°F D638  10 %
Flexural Strength, 73°F D790  24,000 psi
Flexural Modulus of Elasticity D790  600,000 psi
Shear Strength, 73°F D732  16,000 psi
Compressive Strength – Ultimate psi
Compressive Strength at 2% Deformation D695 psi
Compressive Strength at 10% Deformation D695  24,000 psi
Deformation Under Load %
Compressive Modulus of Elasticity, 73°F D695  478,000
Compressive Strength ⊥ to Laminate (Modulus) psi
Compressive Strength ⊥ to Laminate (Yield) psi
Compressive Strength ⊥ to Laminate (Ultimate) psi
Hardness, Durometer (Shore “D” scale) D2240     –
Hardness, Rockwell (Scale as noted) D785 E80 (M120) Rockwell M
Izod Impact, Notched @ 73°F D256 Type A  2.0 ft.lbs/in. of notch
Coefficient of Friction (Dry vs Steel) Static PTM55007
Coefficient of Friction (Dry vs Steel) Dynamic PTM55007  0.35
Maximum Static Bearing Load (P) PTM55007 psi
Maximum Unlubricated No Load Bearing Velocity (V) PTM55007 ft/minute
Maximum Limiting PV (Unlubricated) PTM55007  12,000 psi x ft/min.
Wear Factor “K” x 10-10 PTM55010  35 Cubic in.-min/
Sand Wheel Wear/Abrasion Test UHMW=100
Minimum Mating Surface Hardness Rockwell (Brinnell)
Coefficient of Linear Thermal Expansion E-831(TMA)  1.7 in/in/°F x 10-5
Coefficient of Thermal Expansion // to Laminates E-831(TMA) in/in/°F x 10-5
Coefficient of Thermal Expansion I to Laminates E-831(TMA) in/in/°F x 10-5
Softening Point °F
Heat Deflection Temperature 264 psi D648  532 °F
Embrittlement Temperature °F Min.
Continuous Service Temperature in Air  500 °F Max.
Short Term Service Temperature °F Max.
Tg-Glass Transition (Amorphous) D3418  527 °F
Melting Point (Crystalline) Peak D3418  N/A °F
Thermal Conductivity F433  1.80 BTU-in/(hr/ft2°F)
Dielectric Strength Short Term D149  580 Volts/mil
Volume Resistivity D257 ohm/cm
Surface Resistivity D257  >1013 ohm/cm
Dielectric Constant, 106 Hz D150  4.2
Dissipation Factor, 106 Hz D150 0.026
Flammability @ 3.1mm(1/8 in.) UL94 UL94 V-O
Arc Resistance seconds
Water Absorption, Immersion 24 Hours D570 (2) 0.4 %
Water Absorption, Immersion Saturation D570 (2) 1.7 %
Machinability Rating 5 1=easy, 10=difficult
Rod Diameter Availability (Off the Shelf) .093-2.0 inches
Sheet Thickness Availability (Off the Shelf) .187-1.0 inches
Characteristics / Attributes Very high compressive and impact strength / Great insulation properties / Excellent Bearing Properties