Influence of friction on imperfect conical indentation for elastoplastic material

The investigation of this paper provides a rationale of the influence of friction in nanoindentation testing for elastoplastic solids. The emphasis is placed on providing a detailed evaluation of the influence of the friction coefficient on the calculated hardness using an imperfect indenter. A new method for calculating the material hardness is derived. The new function can take into account the combined effects of friction and imperfect indenter tip geometry. For further investigations, some numerical simulations are executed. The results show that the new function can provide a good relationship for the hardness calculated in all friction cases. Moreover, the numerical simulations show that the friction coefficient does not significantly affect the curve of load versus indentation depth, whereas it significantly influences the deformations of the specimen surface around the indenter for some materials.