2.6. Abrasion measurement
Abrasion loss measurement was performed on samples by using
an abrasion tester of the type AP.40 (MASCHINEBAU GmbH
RAUENSTEIN THURINGEN, Germany).
The testes were carried out under the following conditions:
Load = 1 kg.
Abrasion path = 40 meter which equivalent to 84 revolutions.
The loss in the mass was calculated according to following
equation: