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ASTM D3702 Friction and Wear Test For of Materials in Self-Lubricated Rubbing Contact

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ASTM D3702 Standard Test Method for Wear Rate and Coefficient of Friction of Materials in Self-Lubricated Rubbing Contact Using a Thrust Washer Testing Machine


ASTM D3702 test method covers the determination of wear rate and coefficient of friction for self-lubricated materials in rubbing contact by a testing machine2 that utilizes a thrust washer specimen configuration. 

This test method is used to determine the equilibrium rate of wear and coefficient of friction of materials in rubbing contact under useful operating conditions, that is, combinations of pressure and velocity that fall below the PV (pressure × velocity) limit of the test material. The user of this test method should determine to his own satisfaction whether the results of this test procedure correlate with field performance or other bench test machines. If the test conditions are changed, the wear rates may change and the relative value of one material with respect to another may also change.


Test Principle:

The test simulates rotational sliding wear under a specific load, speed, and geometry. A stationary "thrust washer" specimen is pressed against a rotating ring or washer under a known axial force. The principle is to measure the volume of material lost from the test specimen due to wear over a set duration or number of cycles, thereby calculating the wear rate.

The test specimen rotates against a stationary steel washer under a controlled normal load (via dead weights).

A 40‑hour break‑in period stabilizes contact and establishes steady‑state rubbing.

During testing: Torque is measured to calculate coefficient of friction (COF = Torque / (Load × Radius)).

Linear wear depth or mass loss is measured over time to compute wear rate (mm/h or g/h).

Tests run at PV values below the material’s failure limit; typical durations: 50–4000 hours (to achieve ≥0.1 mm wear for precision).


Pressure (P) and Velocity (V) are two key determinants of performance for a dynamic load-bearing component. P is the load on the component and measured in MPa or psi units; V is the velocity or speed at which the mating surfaces are in contact, measured in units of length over time; e.g., cm or feet / minute. 

This testing is typically done on a thrust washer set-up as shown in Figure.

ASTM D3702 Friction and Wear Test For of Materials in Self-Lubricated Rubbing Contact


V is calculated by multiplying Pressure x Velocity to which the material is exposed. 

The combination of these variables creates frictional heat at the mating surface of the sample. When the PV exceeds a material's capability, the heat generated can cause failure of the load bearing component.


Limiting PV defines the maximum PV that a material can withstand with no lubrication at the mating surfaces. When the actual PV that occurs under operating conditions exceeds the plastic's Limiting PV, the material will likely fail due to surface melting or excessive wear.


ASTM D3702 Friction and Wear Test Procedures: 

Specimen preparation: Machine, clean, measure dimensions, and weigh.

Machine setup: Install specimen and steel counterface; apply dead weight for target load; set spindle speed.

Break‑in: Run 40 hours at test conditions to stabilize contact.

Steady‑state testing:

Record torque (for COF) continuously.

Measure wear depth (or mass) at intervals.

Continue until ≥0.1 mm wear or specified duration is reached.

Data calculation:

Wear rate = Total wear / Test time (mm/h or g/h).

COF = Average friction torque / (Normal load × Mean radius).

Report: Include test conditions (load, speed, PV, temp), wear rate, COF, and specimen details.


Standard related: 

ASTM D2714Standard Test Method for Calibration and Operation of the Falex Block-on-Ring Friction and Wear Testing Machine
ASTM G99Standard Test Method for Wear and Friction Testing with a Pin-on-Disk or Ball-on-Disk Apparatus. 
ASTM G77Standard Test Method for Ranking Resistance of Materials to Sliding Wear Using Block-on-Ring Wear Test
ASTM D4172Standard Test Method for Wear Preventive Characteristics of Lubricating Fluid (Four-Ball Method)
ISO 7148-2Plain bearings - Testing of the tribological behaviour of bearing materials - Part 2: Testing of polymer-based bearing materials.
ASTM D2266Standard Test Method for Wear Preventive Characteristics of Lubricating Grease (Four-Ball Method)


Related products and device

ASTM D3702 Thrust Washer Friction Testing Machine

Thrust Washer Friction Testing Machine can be used to evaluate the friction and wear performance of lubricants and materials such as metals, plastics, coatings, rubber, and ceramics under very low speed or high speed with method of Self-Lubricated Rubbing Contact Using a Thrust Washer.

ASTM D3702 Vertical Universal Friction & Wear Test Machine

Vertical Universal Friction Wear Test Machine is similar to an the FALEX Multi Specimen Test machine in main application and functions, it's widely used as imitation inspection testing machine in design and develop hydraulic oil, combustion engine oil, gear oil etc..

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