Effect of sandblasting defects distribution on the mechanical strength of a soda-lime glass

Abstract

Erosion tests were carried out to study the influence of sandblasting defects on the flexural strength R (ring-on-ring) of a soda-lime glass by varying the sand impact velocity V and impact angle α. Constant sand mass (30 g) and particles size (1000 μm) were used. The results show that the surface damage increases as V increases, and when α tends towards 90°. The maximum damage rate reached is about 52%. For low sandblasting conditions (V = 15 m/s, α = 30°), R is in the order of 103.6 MPa, while for the most severe conditions, R is reduced to 17.4 MPa. The Weibull analysis allowed seeing the effect of erosion parameters taken separately and taken all together. In the first case, the defects distributions are unimodal and the Weibull modulus m varies in the range (7 ÷ 19). Considering all the parameters together, the distribution becomes bimodal with a good agreement between the experimental values and the chi square approximation. So, we have concluded that there are two families of defects that govern the flexural strength: • Those corresponding to low sizes (low impact angles and velocities) and great values of R; • Those corresponding to great sizes (high impact angles and velocities) and low values of R. The strength distribution is found to be partially concurrent. A function relating the impact angles and sand flow velocities to the flexural strength is introduced. The experimental data obtained seem to correspond well to the proposed function.