Wedge indentation of elastoplastic solids — from single indentation to interaction between indenters

Performance of metallic seals used between face-turned surfaces is related to their abilities to flow plastically in order to fill up cavities between wedge-shaped asperities. Double wedge indentation is therefore a simple way to investigate what happens at such a seal-flange interface. In this paper, finite element analyses of single and double wedge indentations are conducted. A particular attention is paid to the effects of hardening parameters on the resulting hardness. First, it is observed that single wedge indentation hardness can be well-approximated by the adaptation of analytic models initially developed for cone indentation problems. Second, it is shown that interaction between indentation-strain field during double wedge indentation starts once the bearing ratio is about 25%. It leads to a significant mean contact pressure increase, which is strongly dependent upon the strain hardening exponent. Eventually, for a bearing ratio higher than 75%, a plastic locking stage occurs, which leads to an exponential increase of the mean contact pressure. Practical applications of this work to indentation and sealing research fields are discussed.