Microabrasion (TE66) Tribometer

The rotation of a ball against a coated plate in the presence of an abrasive slurry results in the production of a circular depression. Eventually the coating is worn through and a “bulls-eye” depression is seen where the substrate shows through. Measurements of the inner and outer diameters of this bulls-eye are easily made and provide an accurate and low cost method of determining coating thickness. This is an established coating thickness measurement technique.

In order to use this configuration for wear coefficient determination it is necessary to measure precisely ball rotational speed, applied load and number of rotations completed (for sliding distance determination). The aim of such a test is to measure progressive wear over an extended number of cycles and thus determine wear rates and wear coefficients of the material (and coating).

In the TE 66 Micro-Scale Abrasion Tester, manufactured by Phoenix Tribology Ltd.,  the ball is fixed into the rotating shaft and the test surface is mounted on a counterbalanced beam that hangs vertically from a pivot.

A 25 mm ball is clamped between two coaxial shafts each carried in support bearings. One shaft is driven by a variable speed dc geared motor. A batch counter is provided to measure and control the number of shaft revolutions.

The test sample is clamped onto a platform on a vertical beam. The beam is in balance when the samples are just in contact and the load is applied by adding dead weights to a cantilever arm.

Slurry is stored in a container that can be agitated on a laboratory magnetic stirrer. A peristaltic pump is provided for pumping the slurry into the contact. It is fed to a position just above the contact point and collected in a waste tray underneath.

The TE66 conforms to: BS EN 1071-6: 2007