A FINITE-ELEMENT STUDY OF THE INDENTATION MECHANICS OF AN ADHESIVELY BONDED LAYERED SOLID

The objective of this work is to study the mechanics of indentation of an adhesively bonded layered solid. To this end, several (plane strai n) finite element simulations of wedge indentation of a ductile strip which is adhesively bonded to a rigid substrate are conducted by varyi ng the properties of the adhesive layer. The stress fields below the i ndenter tip and at the strip-adhesive interface are examined for Vario us depths of indentation. The effects of the adhesive properties on th e above features of the finite element solution, as well as on the har dness versus penetration characteristics, are investigated. The above results are also compared with those for an unbonded strip resting on a frictionless surface. It is found that once yielding commences in th e adhesive layer, the state of stress in it is comprised of a shear st ress and a superposed hydrostatic compression. Also, it is observed th at increasing the yield strength of the adhesive layer significantly d elays the onset of the decreasing phase of the hardness versus penetra tion curve, whereas, changing the elastic modulus of the adhesive has negligible effect on it. (C) 1997 Published by Elsevier Science Ltd.