UHMW (Ultra High Molecular Weight Polyethylene)

UHMW is an acronym for Ultra High Molecular Weight Polyethylene.  Most commonly referred to as UHMW. It is famous for its abrasive resistance, toughness, and low cost.  It is also FDA and NSF compliant.  It’s natural color is white, but is available in black and other colors at special request.  Typical applications include sleeve and flanged bearings for high wear industrial and manufacturing bearing applications.  Custom and standard profiles exist for conveying environments. UHMW is easily machined into custom components.  Though it is easily machined with standard metal working equipment, UHMW has a very high coefficient of thermal expansion making it difficult to hold close tolerance dimensions.  Its main attributes are impact and abrasion resistance.  Its self-lubrication properties and low cost makes UHMW a great choice for many demanding bearing and wear applications.

UHMW is available in many filled varieties, including glass, oil, MS02, thereby enhancing its bearing and wear properties to extreme levels.

Specification Test Value Units
Density, 73°F D792 .93 gm/cm3
Tensile Strength @ Yield, 73°F D638 5800 psi
Tensile Modulus of Elasticity, 73°F D638 120,000 psi
Tensile Elongation (at break), 73°F D638 200 %
Flexural Strength, 73°F D790 psi
Flexural Modulus of Elasticity D790 110,000 psi
Shear Strength, 73°F D732 psi
Compressive Strength – Ultimate 750 psi
Compressive Strength at 2% Deformation D695 psi
Compressive Strength at 10% Deformation D695 1,000 psi
Deformation Under Load %
Compressive Modulus of Elasticity, 73°F D695
Compressive Strength ⊥ to Laminate (Modulus) 750 psi
Compressive Strength ⊥ to Laminate (Yield) 750 psi
Compressive Strength ⊥ to Laminate (Ultimate) 750 psi
Hardness, Durometer (Shore “D” scale) D2240 68
Hardness, Rockwell (Scale as noted) D785 Rockwell M
Izod Impact, Notched @ 73°F D256 Type A No Break ft.lbs/in. of notch
Coefficient of Friction (Dry vs Steel) Static PTM55007 .15-.20
Coefficient of Friction (Dry vs Steel) Dynamic PTM55007 .10-.14
Maximum Static Bearing Load (P) PTM55007 750 psi
Maximum Unlubricated No Load Bearing Velocity (V) PTM55007 15 ft/minute
Maximum Limiting PV (Unlubricated) PTM55007 750 psi x ft/min.
Wear Factor “K” x 10-10 PTM55010 Cubic in.-min/ft.lbs.hr
Sand Wheel Wear/Abrasion Test 100 UHMW=100
Minimum Mating Surface Hardness 20 Rockwell (Brinnell)
Coefficient of Linear Thermal Expansion E-831(TMA) 11 in/in/°F x 10-5
Coefficient of Thermal Expansion // to Laminates E-831(TMA) 11 in/in/°F x 10-5
Coefficient of Thermal Expansion I to Laminates E-831(TMA) 11 in/in/°F x 10-5
Softening Point 180 °F
Heat Deflection Temperature 264 psi D648 °F
Embrittlement Temperature °F Min.
Continuous Service Temperature in Air 180 °F Max.
Short Term Service Temperature 200 °F Max.
Tg-Glass Transition (Amorphous) D3418 °F
Melting Point (Crystalline) Peak D3418 °F
Thermal Conductivity F433 BTU-in/(hr/ft2°F)
Dielectric Strength Short Term D149 Volts/mil
Volume Resistivity D257 ohm/cm
Surface Resistivity D257 ohm/cm
Dielectric Constant, 106 Hz D150  2.3-2.35
Dissipation Factor, 106 Hz D150  <.5 x10-3
Flammability @ 3.1mm(1/8 in.) UL94 UL94 HB
Arc Resistance seconds
Water Absorption, Immersion 24 Hours D570 (2) Nil %
Water Absorption, Immersion Saturation D570 (2) Nil %
Machinability Rating 3 1=easy, 10=difficult
Rod Diameter Availability (Off the Shelf)  .50 10 inches
Sheet Thickness Availability (Off the Shelf) .125 3.5 inches
Characteristics / Attributes Excellent Abrasion and Impact Resistance, Easily Machined, Low Cost