Figure 2
From: Revealing the surface structural cause of scratch formation on soda-lime-silica glass
(a) Statistical analysis of hardness of untreated and heat-treated glass surfaces at a load of 10 mN for 16 indentations performed across an array of 4 × 4. The p-value reported by ANOVA test indicates that the means are significantly different at the 0.001 level. (b) Comparative illustration of the mean of variation in hardness as a function of depth from the untreated and heat-treated SLS glass surfaces. The indentation size effect (ISE) due to dislocation strengthening necessary to accommodate plastic deformation, in addition to friction between the indenter and specimen surface39,40, may not be neglected at shallow depths below 100 nm. The Martens hardness in the ordinate (y-axis) contains an axis-break. (c) Corresponding mean load–displacement curves illustrating the loading cycle (AB: untreated and AB’: H510) and unloading cycle representative of elastic recovery (BC: untreated and B’C’: H510). The serration observed in the unloading cycle (B’C’) of the H510 specimen reflects local relaxation processes during elastic recovery, which is predominantly more active during the unloading process than during loading41.
