In this study, dry sliding and abrasive wear behaviour of Al - 70 vol.-%Al2O3 particulate composite alloyed with Mg was examined. The composites were produced by a pressure infiltration casting technique. The composition of the matrix varied between 0 and 8 wt-%Mg, and the diameter of the Al2O3 particulates was 60 mum. Dry sliding wear tests were carried out on an unlubricated M2 quality high speed tool steel disc by a pin on disc type wear tester. Abrasive wear tests were run by rubbing the composites on abrasive Al2O3 grains. The results of the wear tests revealed that, both dry sliding and abrasive wear resistance of the composites increased with increasing Mg content in the matrix. MST/5421 Mr Ahlatci. Mr Karakas and Professor Dr Cimenoglu are in the Department of Metallurgical and Materials Engineering, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey (email@example.com). Associate Professor Candan is in the Technical Education Faculty, Division of Metal Casting, Zonguldak Karaehnas University 78100 Karabuk, Turkey. Manuscript received 4 February 2002: accepted 27 August 2002. (C) 2003 IOM Communications Ltd. Published by Maney, for the Institute of Materials, Minerals and Mining.