The Effect of Masterbatching, Compounding, and Testing Variables on Constant-Slip Abrasion Results

Abstract

A study of factors which affect the results obtained with the constant slip abrader in evaluation of abrasion resistance properties of GR-S vulcanizates has revealed the following : 1. As might be expected, abrasion losses decrease with increase in 300 per cent modulus. 2. Losses increase approximately logarithmically as the amount of slip between the test and abrasive wheels increases. 3. The abrasion losses decrease with increase in talcing rate, due to “lubrication” of the abrasive wheel by the talc as long as the rate is sufficient to keep the wheel free of loose abraded material. 4. Indications are that abrasion losses may increase with increase of coefficients of friction of test wheels against the abrasion wheel. 5. In a study of the effect of ambient temperature on constant slip abrasion losses, the losses increased as the temperature was raised from −10 to 30° C for GR-S 1500, GR-S 1503, and for high Mooney-viscosity GR-S 1500 extended with a naphthenic extender oil, and the losses remained essentially constant for the Resin-731 extended high Mooney viscosity GR-S 1500. The Resin-731 extended stock changed only slightly with temperature and, consequently, its comparative rating increased rapidly with rise of temperature. It was noted in photomicrographs of the wheel surfaces that the abrasion pattern which was evident at normal temperatures was absent or at best poorly defined at the lower temperatures, indicating a possible difference in kind of abrasion at low temperatures than at normal temperatures. 6. Latex masterbatches of oil and black that had been premixed by several different methods gave vulcanizates with constant-slip abrasion resistance superior to similar masterbatches prepared in the usual manner. 7. The constant-slip abrader was found to be useful in evaluating new SAF blacks and in the evaluation of the effect of using dispersing agents in carbon black and extender-carbon black masterbatching by the latex procedure.

Characterization of Sticky Debris Generated During Smear Wear

“…This type of abrasion failure is a degradation process which is referred as either smearing or smear wear in the literature. This smear wear, as a distinct class of abrasion mechanism has been reported widely in the literature 11,25,26,27,28,29 . However, only a very limited number of these studies provide a detailed characterisation and discussion of the sticky debris generated by smear wear 30 .…”

“…Unlike most other engineering materials, rubber materials show very different abrasion mechanisms under different circumstances due to their relative low modulus and unique viscoelastic and frictional properties. Over the past century, a wide range of experimental abraders have been developed to predict abrasion performance and to investigate abrasion mechanisms, such as: needle abrader 1 , blade abrader 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , Lambourn abrader 10,11,12 , DIN abrader 13,14,15 , Akron abrader 16,17 , LAT 100 abrader 18,19,20,21 and ball on plane abrader 22 . The generally accepted possible mechanisms of rubber abrasion include abrasive wear, fatigue wear and smear wear.…”

Natural and Synthetic Rubbers

“…In a study of factors influencing the constant-slip abrasion test, Howland and coworkers (77) stressed the advantages of a constant temperature control chamber added to a constant-slip abrader.…”

Design and development of a new portable test setup to study friction and wear

“…However, for many applications, such as rubber friction and wear in shoes and tires, outdoor tests are necessary to obtain data under actual operating conditions. One of the conventional laboratory friction and wear test machines is the Lambourn abrader, [12][13][14] which is made of a sample wheel in contact with a grinding wheel where both sample and grinder wheels are located in the same plane. In this mechanism, a gearbox is used to determine the slip between the rubber wheel and the grinding wheel.…”