Theoretical and computational modelling of instrumented indentation of viscoelastic composites
In this study, we investigate the indentation of viscoelastic composites by using a combination of theoretical and computational analysis. The composite is assumed to consist of two phases, i.e., the filler and the matrix, and they are linear elastic and linear viscoelastic material, respectively. Two cases are investigated: 1). hard fillers are embedded in a very soft matrix; 2). the matrix is much harder than the fillers. Particular attention is paid to the correlation between the indentation responses and the relaxation properties of the composites and the constituent. To this end, we first perform a theoretical analysis which is followed by a series of finite element computations. A number of conclusions have been drawn based on the theoretical and computational results, which may improve the current understanding of the indentation of viscoelastic composite materials, including some man-made biocomposites as well as biological soft tissues.
KeywordsIndentation viscoelastic composites finite element simulation
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