The use of instrumented indentation to characterize the mechanical response of polymeric materials was studied. A model based on contact between a rigid probe and a linear viscoelastic material was used to calculate values for creep compliance and stress relaxation modulus for two crosslinking polymeric materials, an epoxy and poly(dimethyl siloxane) or PDMS. The use of a rounded conical tip and sharp pyramidal tips produced linear and nonlinear responses from these two polymers depending on tip shape and load level. Results from bulk rheometry studies were used for comparison to the indentation creep and stress relaxation results.
Citation: Journal of Materials Research
Pub Type: Journals
creep, mechanical propeties, mechanical response, modulus, nanoindentation, polymer