基于纳米压痕技术的电子玻璃微观力学性能研究

为了研究不同电子玻璃的微观力学性能，采用先进的纳米压痕技术记录钠钙硅、无碱硼铝硅和碱铝硅等典型电子玻璃的载荷-位移曲线，利用Oliver-Pharr方法和经典的弹塑性变形理论，计算玻璃的硬度和弹性模量. 玻璃的硬度主要与结构的键合度相关，平均非桥氧数越高，外力作用下越容易致密化，硬度越小；弹性模量主要取决于质点间的化学键强度，化学键力越强，变形越小，弹性模量越大；九点法测得的弹性模量与硬度的变化趋势不完全相同，借助硬度-弹性模量-能量耗散之间的本征关系，评价玻璃样品的微观均匀性，其中无碱硼铝硅玻璃的恢复阻力大，局部能量耗散大，不容易引起整体破坏，力学性能最好；与浮法工艺相比，溢流下拉法制备样品的局部力学性能波动较小，微观均匀性较好.

Micromechanical properties of electronic glass using nanoindentation technology

Advanced nanoindentation technology was used to record load-displacement curves of typical electronic glasses, including soda lime silicate, alkali-free boroaluminosilicate and alkali aluminosilicate glasses, in order to study the microscopic mechanical properties of different electronic glasses. Hardness and elastic modulus were calculated using the Oliver-Pharr method and elastoplastic deformation theory. The hardness of glass is mainly related to the bonding degree of glass structure. The higher the average number of non-bridging oxygen, the easier it is to densify under stress, thus the lower the hardness. The elastic modulus mainly depends on the strength of chemical bond between particles. Stronger chemical bond leads to smaller deformation and larger elastic modulus. Different trends were observed for the elastic modulus and the hardness measured by the nine-point method. Microscopic uniformity of the glass samples has been evaluated based on the intrinsic relationship between hardness, elastic modulus and energy dissipation. Results showed that the alkali-free boroaluminosilicate glass had the best mechanical properties with high recovery resistance and local energy dissipation, making it not easy to cause overall damage. Samples prepared by overflow down-draw process showed less fluctuations in the local mechanical properties and got better micromechanical uniformity compared with samples prepared by float process.