PSI - Issue 42

Erik Calvo-García et al. / Procedia Structural Integrity 42 (2022) 251–258 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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The lower values of processing speeds leaded to lower enhancements. The 26 degree average slip angle of the unmodified glass surface in dry conditions is doubled by laser blasting with intermediate and high values of processing speeds. The enhancement in water and oil wet conditions can be averaged to three and four times the slip angle value of the unmodified glass surface. The results of fracture toughness from the radial cracks after Vickers micro-indentation, see Fig.3, reveals that the soundness of the glass is mainly preserved at local level. Nevertheless, the slight reductions of fracture toughness allow to select an optimal value of 0.23 J/mm 2 for the treatment of annealed soda-lime silicate glass. K IC values around 0.81 MPa·m 1/2 were obtained for the reference annealed glass and the optimal processing conditions. These values are in well agreement to those reported for soda-lime silicate glass by Gong et al. (2021), Rouxel (2017), To et al. (2021) and Lai et al. (2021). a) b)

c)

d)

Figure 3. Radial cracks produced after Vickers indentation of: a) Annealed reference glass; b) heat treated reference glass; c) annealed laser blasted glass; d) heat treated laser blasted glass. a) b)

Figure 4 – a) Experimental fracture surface energy as a function of the laser-blasting energy. b) Registered normal strain on the compressed surface for different four-point bending test speeds