The Hertzian failure theory describing the maximum contact pressure developed when a cylinder and a flat plate are loaded under a force was in good agreement with exptl. data on some typical low-temperature isotropic (LTI) C-coated heart valve components.Whenever C was loaded in a point-or-line-contact, this mode of failure might dominate all other factors.Designs of housing and occluders must take this factor into consideration.Mishandling of C components, e.g. SiC-tipped forceps or prying the ocular against the housing, will nucleate Hertzian failure.
