Work

Low-temperature co-sintering repair of cracked borosilicate glass-to-metal seals using a phosphate glass adhesive

Year: 2026

Type: article

Abstract: Borosilicate glass-to-metal seals (BSGTMs) are prone to brittle cracking induced by thermal stress mismatch in extreme environments such as nuclear power and aerospace applications, leading to seal failure and resource wastage. However, existing research predominantly focuses on failure prevention, while the fundamental theory and technical approaches for repairing post-service damage remain unexplored. This study proposes a novel strategy for low-temperature co-sintering repair of borosilicate glass (BSG) utilizing low-softening-point phosphate glass (PG) as the bonding agent. By regulating the wetting-infiltration-adhesion behavior of PG, structural and functional regeneration of BSG and its sealed assemblies was achieved. The wetting kinetics and interfacial reaction mechanisms of PG on BSG under the coupled effects of repair temperature and holding time were elucidated. Insufficient wetting at low temperatures and short durations resulted in pore or crack formation, whereas excessive thermal deformation of the substrate occurred at high temperatures and prolonged durations, both compromising the repair efficacy. The optimal parameters were identified as 550 °C for 50 min, yielding a recovery of mechanical performance exceeding approximately 85% for both the repaired BSG and its sealing assemblies. This research provides theoretical foundations and a technical prototype for the emergency repair of brittle glass materials and heterogeneous sealing components, transcending the traditional limitation of discard-upon-failure, and holds significant engineering value for extending the service life of high-value sealing structures and enhancing resource utilization efficiency.

Source: Journal of Alloys and Compounds

DOI: 10.1016/j.jallcom.2026.189818