A note on the elastic contact stiffness of a layered medium

A perturbation method is used to confirm that the elastic contact stiffness associated with a flat-ended punch indenting a layered medium is insensitive to the cross-section shape of the punch as long as the shape does not differ too much from a circle. This result supports the practice of modeling nonaxisymmetric indenters such as Vickers or Berkovich indenters as an axisymmetric flat-ended cylindrical punch. © 1993, Materials Research Society. All rights reserved.