William W. Gerberich, Associate Fellow

Modeling of Micro- and Nanoindentation of Solidified/Solidifying Polymeric Coatings

The purpose of this research was to develop an efficient model for microand nanoindentation of solidified/solidifying polymeric coatings and to probe mechanical properties of polymers with both nanoindentation technique and the model. In the previous stage of this research, two- and three-dimensional explicit finite difference models of elasto-plastic micro- and nanoindention and microscratch with large deformation were developed and run successfully on the Crays.

Most recently, this research was extended to the modeling of micro- and nanoindentation of viscoelastic polymers using specially developed code on the SGI Origin 2000 and IBM SP. The model was applied to relaxation and creep responses in viscoelastic nanoindentation. Three kinds of indenters are of interest to these researchers: strip, flat-ended cylindrical, and spherical. It was expected that the model would consider both compressible and incompressible polymeric coatings, and that this model would assist in applying nanoindentation technique to data acquisition of viscoelastic materials more efficiently.

Research Group

Liangsheng Cheng, Research Associate
Ioannis Karapanagiotis, Research Associate
Donald Kramer, Graduate Student Researcher
Alex Volinsky, Graduate Student Researcher
Xinyun Xia, Graduate Student Researcher
Karl Yoder, Research Associate