An. Gent et C. Nah, ABRASION OF RUBBER BY A BLADE ABRADER - EFFECT OF BLADE SHARPNESS ANDTEST TEMPERATURE FOR SELECTED COMPOUNDS, Rubber chemistry and technology, 69(5), 1996, pp. 819-833
Apparatus has been constructed to abrade the flat surface of a rubber
disk by rotating it against a stationary knife-blade scraper at consta
nt frictional torque. The ratio of worn surface area to sample volume
is relatively large, giving high sensitivity of measurement. Rates of
abrasion were measured for several rubber compounds over a range of fr
ictional torque from 0.05 to 1.2 Nm, corresponding to frictional work
input from 150 to 3,600 J/m(2) per rotation. For some materials, notab
ly SBR compounds, the rate of abrasion decreased markedly as the exper
iment continued, due to rapid wear and blunting of the blade. Polybuta
diene compounds caused much slower wear. Different blades were worn aw
ay at different rates, a zirconia blade showing the least wear. Also,
different elastomers showed different sensitivities to blade sharpness
, the rate of abrasion of a high-styrene (48%) SBR compound being redu
ced the most with a blunted blade whereas the abrasion rate of polybut
adiene (BR) was much less affected. Measurements were carried out with
blades of known sharpness for several representative rubber compounds
at various frictional torques and at two temperatures, 25 degrees C a
nd 100 degrees C. The high-styrene SBR compound showed the lowest rate
of abrasion. Unusually rapid abrasion was observed for SBR and BR com
pounds when the frictional work input exceeded a critical value, close
to the tear( fracture) energy at the same temperature. Also, periodic
fluctuations in rate of abrasion were observed for rapidly-aging comp
ounds at high temperatures. This is attributed to repeated formation a
nd removal of a weakened surface layer.