Correlation between multistage crack growth and time-dependent strength in commercial silicate glasses Part 2. Influence of surface treatment

Abstract

The influence of surface treatment on the fatigue behaviour of commercial glasses is investigated; especially as to whether or not the fatigue behaviour of glass specimens with well-defined surface damage can be predicted from macroscopic crack growth data by means of the fracture mechanical model, if the specimens are submitted to corrosive or heat treatment after the damage has been applied but before the fracture test was performed. The results show that the correlation between macroscopic crack growth and fatigue behaviour of such specimens is only of restricted validity. Differences become obvious in the range of the long-term strength (which is of special practical interest) as the relative fatigue limit and the slope n1 in region 1 are increased. This means that the tendency to fatigue is reduced through the additional treatment.