Sealing glass will inevitably generate bubbles during manufacturing processes. According to the test results of mechanical properties and micromorphology, porosity is likely to be pivotal in controlling the mechanical behaviour of glass. A multiscale finite element model of the extended finite element method (XFEM) coupled with a representative volume element (RVE) was established to elucidate the effect of bubbles on glass fracture behaviour. Combining experimental measurements and simulations, the crack initiation mechanism was explained, and the fracture regularity was described. It is found that the micron bubbles will seriously deteriorate the compressive properties of glass, but have little effect under the tensile load. The behaviour of the glass can be greatly improved by controlling the bubbles. The bubble size of smaller than 5 μm and the inter-bubble distance of more than twice the diameter were suggested via a single bubble simulation under unidirectional stress. The findings are of great significance for understanding the influence of bubbles on the fracture behaviour of glasses.

封接玻璃在制造过程中难免会产生气泡。根据力学性能和微观形态的测试结果，孔隙率可能是控制玻璃力学行为的关键。建立了扩展有限元法 (XFEM) 与代表性体积元 (RVE) 相结合的多尺度有限元模型，以阐明气泡对玻璃破裂行为的影响。结合实验测量和模拟，解释了裂纹萌生机制，并描述了断裂规律。发现微米气泡会严重恶化玻璃的压缩性能，但在拉伸载荷下影响不大。通过控制气泡可以大大改善玻璃的性能。通过单向应力下的单个气泡模拟建议小于 5 μm 的气泡尺寸和大于两倍直径的气泡间距离。该发现对于理解气泡对玻璃断裂行为的影响具有重要意义。