散射光弹性技术在化学钢化玻璃表面应力测量中的应用

在智能手机、平板电脑等电子产品领域,化学钢化超薄玻璃的需求不断增加,而玻璃是易碎材料,要提高或保持强度和抗破碎能力,必须正确认识应力分布。如何有效的测量化学钢化玻璃的表面压应力(CS)和压应力层厚度(DOL),是当下一个迫切需要解决的问题。散射光弹性法是利用通过玻璃内部应力的双折射来改变极化激光束的延迟,并且散射光的强度随着激光束的延迟的变化而改变,最后通过偏振光光路上因激光束的延迟而出现的光程差和偏振特性来计算表面压应力和压应力层厚度。对散射光弹性法测量化学钢化玻璃的表面应力的理论依据、测量技术等进行了介绍。

Measurement of Surface Stress of Chemically Strengthened Glass by Scattered Light Photoelasticity

In electronic products,such as smart phones,tablet computers,etc.,the demand for chemically strengthened ultra-thin glass is constantly increasing.Due to the fact that glass is a sort of fragile material,in order to improve or maintain its high mechanical strength and crush resistance it is necessary to understand stress distribution accurately.How to effectively measure the surface compressive stress (CS) and the depth of compressive stress layer (DOL) of chemically strengthened glass is a main problem to be urgently solved.The scattering photoelastic method utilizes the birefringence caused by the internal stress of the glass to change the delay of the laser beam.The intensity of the scattered light also changes with the delay variation.Finally,through the optical path difference due to the delay of the laser beam and the characteristic of the polarized light,the surface compressive stress and the depth of compressive stress layer were calculated.The theoretical basis and measurement techniques for the measurement of surface stress of chemically strengthened glass by scattered light photoelasticity were expounded.