Indentation by nominally flat or conical indenters with rounded corners

Axisymmetric indentation of a flat surface is considered: specifically, the case of flat-ended indenter with rounded edges, and the case of a shallow cone with a rounded tip. Analytical solutions are obtained for the normal a nd sequential tangential loading, in both full or partial slip conditions ( with the Cattaneo-Mindlin approximation), and for the complete interior str ess field in all these conditions. Implications for strength of the contact are discussed with reference to metallic or brittle materials, with the in tention to shed more light in particular to the understanding of common 'fr etting fatigue' or 'indentation' testings with nominally flat or conical in denters. It is found that the strength of the contact, which is nominally z ero for perfectly sharp flat or conical indenters, is well defined even far a small radius of curvature. This is particularly true for the flat indent er, for which the strength is even significantly higher than for the classi cal Hertzian indenter for a wide range of geometrical and loading condition s, rendering it very attractive for design purposes. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.