Weibull parameters and the tensile strength of porous phosphate glass-ceramics

The strengths of porous phosphate glass-ceramic specimens, with relative de nsities ranging between 0.25 and 0.50, were measured by four-point bending at room temperature. An analysis of the data, using Weibull statistics, ind icated that such a treatment, usually performed on dense ceramics, can also be used on porous materials. In the sets studied, the nature of critical f laws was determined, which led to the proposal of a mechanism of fracture i nitiation in such porous materials.