Analysis of Knoop indentation

Knoop indentation tests have long been a standard method for material characterization due to the fact that they provide an easy, inexpensive non destructive and objective method of evaluating basic properties from small volumes of materials. In spite of the broad use, Knoop indentation has never been analysed and its methodology is basically empirical. The present work presents an extensive finite element study on the adhesionless contact of flat surfaces by Knoop indenter. The aim of this work is to explore the theoretical foundation for the commonly used Knoop test and shed light to the interesting details that make the Knoop test so useful and simple. Both elastic and elastoplastic responses are explored. The material of the contacting solid is modeled as homogeneous and isotropic. The effect of the Coulomb friction at the contact region is also considered. Subsequently, the computational results presented in the current study are compared with analytical and experimental results that exist in bibliography.