The present study considers a finite element analysis of elastic-plastic axi-symmetric hemispherical contact for a frictionless deformable sphere pressed by a rigid flat. The material of the sphere is modeled as elastic perfectly plastic. Analysis is carried out to study the effect of varying modulus of elasticity and sphere radius in wide range of dimensionless interference until the inception of plasticity as well as in plastic range. Results are compared with previous elastic-plastic models. It is found that materials with Young’s modulus to yield strength (E/Y) ratio less than and greater than 300 show strikingly different contact phenomena. The dependency of E on dimensionless interference at which the plastic region fully covers the surface is observed. However with different radius, finite element study exhibits similar elastic-plastic phenomena.
Y. Zhao, D. M. Maietta and L. Chang, “An Asperity Micro Contact Model Incorporating the Transition from Elastic Deformation to Fully Plastic Flow”, Journal of Tribology, Vol. 122, No. 1, 2000, pp. 86-93.
V. Brizmer, Y. Kligerman and I. Etsion, “The Effect of Contact Conditions and Material Properties on the Elasticity Terminus of a Spherical Contact,” International Journal of Solids and Structures, Vol. 43, 2005, pp. 5736-5749.