Test method for abrasion behavior of tire tread compounds using the wear particles

Abstract

The abrasion behavior of model tire tread compounds was characterized by the shapes and size distributions of their wear particles. Carbon black-filled NR/BR vulcanizates with varying compositions (NR/BR = 100/0, 80/20, and 60/40) were used. These were thermally aged at 80 °C for 30 days. The wear particles produced from the aged specimen had rougher shapes than those produced from the unaged specimen. The size distributions of wear particles for the aged specimen were smaller than those for the unaged specimen. The wear particles produced from the NR = 100 sample had a larger size distribution than those produced from the NR/BR blend samples. The size distributions of wear particles smaller than 500 μm were found to be closely related to the crosslink density irrespective of the rubber composition and thermal aging. The aged samples exhibited narrower abrasion patterns than their unaged samples. Furthermore, the spacing and depth decreased as the BR content increased. The abrasion patterns were closely related to the size distributions of wear particles. The abrasion rates and the number of wear particles significantly increased after the thermal aging. The abrasion behavior was mainly affected by the crosslink density, rubber composition, presence of antidegradants, and tensile strength. By analyzing the shapes and size distributions of the wear particles and the crosslink densities, the abrasion behavior could be further elucidated.