Microcharacterization and identification of tire debris in heterogeneous laboratory and environmental specimens

Tire debris is produced by the normal wear of tires. Two problems are addre ssed herewith: characterization of debris particles and their identificatio n in heterogeneous specimens, which come from laboratory wear tests and fro m the environment. Both problems are solved by analytical electron microsco py (EM). The scanning electron microscope (SEM) shows that tire debris has a typical, warped surface and pores, and that its characteristic elements, detected by energy dispersive X-ray spectroscopy (EDXS), are S and Zn. As a consequence, the identification of tire debris particles in heterogeneous laboratory specimens is straightforward. In those environmental specimens ( road dust), where Zn cannot be detected, identification is possible in some cases, provided morphology, microanalysis, and X-ray mapping are combined. The analytical transmission electron microscope characterizes tire debris on the sub-micrometer scale by imaging, EDXS, and electron diffraction patt erns. The microstructure exhibits typical elastomer-filler clusters. The re presentative elementary volume is found to be approximately 8 x 10(-23) m(3 ). (C) 2001 Elsevier Science Inc. All rights reserved.