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 addressed herewith: characterization of debris particles and their identification in heterogeneous specimens, which come from laboratory wear tests and from the environment. Both problems are solved by analytical electron microscopy (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 patterns. The microstructure exhibits typical elastomer-filler clusters. The representative elementary volume is found to be approximately 8 x 10(-23) m(3). (C) 2001 Elsevier Science Inc. All rights reserved.