Effect of ZrO2 on Structure and Mechanical Properties of CaO-Al2O3-SiO2 Glasses
Abstract
CaO-Al2O3-SiO2 (CAS) glasses doped with ZrO2 were developed by melt-quenching technique, and the thermal stability, network structure and mechanical properties were investigated by Diifferential thermal analysis, Ultraviolet-Visible spectroscopy and electro-mechanical universal testing. The results revealed that mole fraction of ZrO2 less than 4% increased significantly the glass transition temperature, volume density, oxygen atomic packing density and bending strength with the increasing of ZrO2 content, while decrease the optical band gap. As the mole fraction of ZrO2 was more than 4%, the structural stability and mechanical properties became bad with the increase of ZrO2 content. The better properties and dense microstructure were obtained in the glass sample doped with 4% ZrO2 which showed the maximum bending strength (83.67 MPa), the maximum value between crystallization temperature Tx and transition temperature Tg (230.12℃), and the minimum value of optical band gap (3.28 eV). So the proper ZrO2 addition could improve the oxygen atomic packing density, thus significantly improving the structural stability and mechanical properties of the glass.