Nanoindentation methods for viscoelastic characterization of stiff porous materials

Background
Modifying the mechanical properties of the solid phase of a porous material, in this study calcium-silicate-hydrate, is frequently possible by changing synthesis conditions, but changes in these conditions can also influence porosity, which in turn may affect the mechanical properties of the porous material. Experimental methods to decouple porosity from the viscoelastic properties of the porous material will aid in optimization of the structure of the solid phase to achieve the desired mechanical properties.
 
Objective
Explore different nanoindentation techniques in order to determine the viscoelastic properties of the solid phase (without the affect of porosity) of a stiff porous material via experimental methods alone.
 
Methods
Compacted pellets of calcium-silicate-hydrate were prepared with different porosity and subjected to three nanoindentation techniques to determine viscoelastic behavior and the influence of porosity: dynamic, stress relaxation, and creep. Results ..., Compacted pellets of calcium-silicate-hydrate were prepared with different porosity and subjected to three nanoindentation techniques to determine viscoelastic behavior and the influence of porosity: dynamic, stress relaxation, and creep. Results of the porosity and of the viscoelastic behavior measurements were analyzed with a reverse-micromechanics model to determine viscoelastic properties of the solid phase, which has not been achieved previously for calcium-silicate-hydrate. These methods can be used in development and refinement of materials to determine how changes in the solid phase (e.g. molecular structure) influence viscoelastic behavior while considering the effect of porosity., , # Nanoindentation Methods for Viscoelastic Characterization of Stiff Porous Materials

This data set contains data from three different types of nanoindentation experiments (stress relaxation, creep, and dynamic) on two different specimens (calcium-silicate-hydrate with different levels of porosity). The data are organized into folders for each experiment and specimen type.

Stress relaxation:

1. \"Load and Depth\" folder contains the raw data for indents used in analysis
2. .txt file ending in \"SR_analysis.txt\" contains nanoindentation data analyzed by the nanoindenter software package
3. .txt file beginning with \"SR_fittedmean\" contains the mean normalized stress relaxation data with 95% confidence intervals.

Creep:

1. \"Load and Depth\" folder contains the raw data for indents used in analysis
2. .txt file ending in \"crp_analysis.txt\" contains nanoindentation data analyzed by the nanoindenter software package
3. .txt file beginning with \"SC_E_s\" contains the mean solid elastic modulus...