Abrasion Resistance of GR-S Vulcanizates

Abstract

A method for determining the abrasion resistance properties of reinforced vulcanizates was required for evaluating new GR-S type elastomers and carbon blacks developed for use in automobile tire treads. In spite of the fact that past experiences revealed that most laboratory machines are unsatisfactory for testing GR-S vulcanizates, a program for evaluating several machines was undertaken. A Lambourn abrader similar to the one recently adopted by the British Standards Institution for testing elastomer vulcanizates appeared to be most promising, for which reason efforts were expended on constructing a similar machine. The abrader that was constructed and operated to simulate wear brought about by a tire slipping on road surfaces embodied the following four modifications of the British machine: 1. All parts and accessories were either obtained or fabricated in the United States. 2. The electrical eddy current type of brake used in the original Lambourn machine was replaced with a hydraulic, gear pump braking system. 3. Intermittent talcing of the test wheel during operation was specified. 4. A revolution counter equipped with a friction drive wheel, one foot in circumference, was installed to ride on the test wheel for the purpose of conveniently determining test run distances. The conditions for testing vulcanizates were standardized to obtain abrasion loss values that could be expressed in terms of loss in cubic centimeters per 3000 feet of running at 24 per cent slip. Adjustments were made in calculating abrasion ratings from volume loss values to bring them more in line with reported service test ratings.

Elastomers

“…Through testing several abrasion resistance machines, the results with the Lamboum abrader (Dunlop Rubber, Ltd., England) were the most promising, especially with GR-S stocks (1).…”

Characterization of Sticky Debris Generated During Smear Wear

“…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.…”

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.…”