No abstract

Amorphous silica exhibits a complex mechanical response. The elastic regime is highly non linear while plastic flow does not conserve volume, resulting in densification. As a result the quantification of a reliable constitutive equation is a difficult task. We have assessed the potential of micro-pillar compression testing for the investigation of the micromechanical properties of amorphous silica. We have calculated the response of amorphous silica micropillars as predicted by Finite Element Analysis. The results were compared to preliminary micro-compression tests. In the calculations an advanced constitutive law including plastic response, densification and strain hardening was * Email: remi.lacroix@saint-gobain.com. 1This is the pre-peer reviewed version of the following article: International Journal of Applied Glass Science 3 [1] 3643 (2012), which has been published in final form at http: //onlinelibrary.wiley.com/doi/10.1111/j.2041-1294.2011.00075.x/abstract used. Special attention was paid to the evaluation of the impact of substrate compliance, pillar misalignment and friction conditions. We find that amorphous silica is much more amenable than some metals to microcompression experiments due to a comparatively high ratio between yield stress and elastic modulus. The simulations are found to be very consistent with the experimental results. However full agreement cannot be obtained without allowance for the non linear response of amorphous silica in the elastic regime.