Ceramic plates containing many micro-holes are used for MCPs (microchannel plates) for electron amplification, catalytic converters. filters, electrical insulators and thermal conductors in integrated circuits. Several fabrication methods for MCP such as laser drilling and electron beam drilling of ceramic plates have been used. To increase the productivity, the micro-drilling of ceramic green body followed by sintering machined green body has been suggested. In this work, using the experimental results of alumina green body drilling with electro-deposited diamond grit WC micro-drills, a chip flow model on the worn-out micro-drill tip was constructed to estimate the tool life of micro-drills. The axial forces of abrasive grit micro-drills with respect to drilling time and drilling conditions were calculated from the model constructed. Finally, the tool life of micro-drills was estimated using the calculated axial forces under given drilling conditions. (C) 2004 Elsevier Ltd. All rights reserved.