ASTM F732-82 Recip Pin on Flat Joint Prostheses ... - CETR

Evaluation of Friction and Wear Properties of Polymeric Materials for Use in
Total Joint Prostheses Using Micro-Tribometer mod. CETR-UMT 2
<strong>ASTM</strong> <strong>F732</strong>-<strong>82</strong> (reapproved 1991)
Summary of Test Method:
This test method is used to evaluate the friction and wear properties of combinations of materials that are
being considered for use as the bearing surfaces of human total joint replacement prostheses. The test method
utilizes a flat-ended polymer cylinder upper specimen and a flat stainless steel lower counterface that is
immersed in bovine blood serum. The load is applied downward onto the cylinder specimen. The flat lower
specimen slides linearly, back and forth under the cylinder specimen. The test parameters are listed below.
Test Parameters
Lubricant Temperature Applied Load Stroke Length Osc. Frequency Duration
Bovine blood serum 37º C 225 N 1 inch 1.0 Hz 70 hrs.
Polymer Specimen: length 13 mm, diameter 9 mm.
Counterface surface finish: 0.026 to 0.05 µm.
UMT Hardware Configuration:
Tribology and Mechanical Testing Unit
Wear is reported as volume loss of the polymeric specimen as a function of sliding distance. Volume loss is
determined by dividing the measured weight loss by the density of the polymer.
The UMT allows for monitoring during the test the actual dynamic normal load, friction force and friction
coefficient, and depth of wear. Optionally, it can measure additional parameters of contact acoustic emission
and temperature.
4” Mounting Block
- PN M30C116
Model DFH-5 Dual Friction/Load Sensor
- range 0.5 to 50N
Suspension PN AM30C110F-4
<strong>Pin</strong> Holder for sensors mod. DFH
Polymer Specimen <strong>Pin</strong>
Counterface Material
Plastic Slurry Tray
Bovine Blood Serum
Lower linear <strong>Recip</strong>rocating Motion Drive
- Manually adjust for 1” travel - mod. RHH
Temperature Chamber - PN AM30D81B
Optional Additional Sensors
- mod. RTD Temperature Sensor
- mod. TMR-150 Temperature Measurement & Recording
1717 Dell Avenue, Campbell, CA 95008, USA
Phone: +1.408.376.4040 Fax: +1.408.376.4050
Application Note
Email: productinfo@bruker-nano.com
Web: www.bruker-axs.com

Application Note
UMT Software Test Setup:
UMT Options File:
Load the options file which contains settings for the Linear <strong>Recip</strong>rocating Motion drive and the 500 N force/load
sensor.
Test Sequence:
The Test Sequence should consist of 2 sheets.
Sheet 1 is for settling time for the carriage to establish the initial normal load.
Carriage - applies a 225 N Constant Force for a Duration of 10 sec.
Spindle Velocity is 0 revs/min.
Slider is idle.
Sheet 2 is for the actual sliding test.
Carriage - applies a 225 N Constant Force for a Duration of 70 hours.
Spindle Velocity is 60 revs/min, Move-Continuous, and Direction- Clockwise
Slider is idle.
Data Collection:
The following should be checked under DataFile:
Fx Friction Force
Fz Normal Force
T Time
Z1 Carriage Position (Used to determine Wear Depth)
Te input Temperature (optional)
Report:
Use the Viewer program to plot test results.
Select the parameters to be displayed by checking
the appropriate box under Parameters on the Viewer screen.
For viewing COF plots of reciprocating tests check the Fz box, click on the Symmetry button, click on the Peak Detect
button, and then check the COF box.
Multiple test results can be viewed at the same time as in the example below.
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Tribology and Mechanical Testing Unit
1717 Dell Avenue, Campbell, CA 95008, USA
Phone: +1.408.376.4040 Fax: +1.408.376.4050
Email: productinfo@bruker-nano.com
Web: www.bruker-axs.com