The phase structure and clay dispersion in polyamide-6(PA6)/polypropylene(PP)/organoclay (70/30/4) systems with and without an additional 5 parts of maleated polypropylene (MAH-g-PP) as a compatibilizer were studied with atomic force microscopy (AFM). AFM scans were taken from the polished surface of specimens that were chemically and physically etched with formic acid and argon ion bombardment, respectively. The latter technique proved to be very sensitive to the blend morphology, as PP was far more resistant to ion bombardment than PA6. In the absence of the MAH-g-PP compatibilizer, the organoclay is located in the PA6 phase; this finding is in line with transmission electron microscopic results. Further, the PP is coarsely dispersed in PA6 and the adhesion between PA6 and PP is poor. The addition of MAH-g-PP resulted in a markedly finer PP dispersion and good interfacial bonding between PA6 and PP. In this blend, the organoclay was likely dispersed in the PA6-grafted PP phase. (c) 2005 Wiley Periodicals, Inc.