Characterization of Young׳s modulus and fracture toughness of albite glass by different techniques

This work compares values of Young׳s modulus and fracture toughness of amorphous albite measured from different experimental techniques. Sodium feldspar powder was used to synthesize the albite glass. After quenching, the microstructure of the amorphous solid was analyzed via scanning electron microscopy and X-ray diffraction. Several nanoindentations on albite samples were carried out with two purposes: determination of Young׳s modulus by continuous stiffness measurement, and critical stress intensity factor by crack size evaluation. Concurrently, impulse excitation technique and three point bending single-edge notched test were adopted for providing the comparison of elasticity and toughness, respectively. Young׳s modulus measured by continuous stiffness yielded a value of 71.8±0.9 GPa, which was in agreement with the value obtained by impulse excitation (72.5±1.3 GPa). The fracture toughness determined by nanoindentation was slightly higher (0.86±0.06 MPa m1/2) than that (0.78±0.06 MPa m1/2) obtained by single-edge notched beam.