After curing, this solvent-free three-component silazane adhesive forms a dense ceramic matrix that maintains stable structure without pulverization under long-term exposure to 800–1000°C. Its standout advantage is notably increased bonding strength after prolonged thermal aging at 400°C and 600°C, and reliable adhesion survives thermal cycling, eliminating the aging failure issue of ordinary high-temperature adhesives. The gray-black paste delivers excellent gap-filling performance, applicable to structural bonding/sealing as well as high-temperature protective coatings. The room-temperature curing process cuts energy consumption, suitable for small-batch sampling and outdoor equipment repair. Flexible customizable sizes and easy storage. Ventilation is required during operation due to ammonia emission, serving as a long-lasting bonding and protection material for industrial kilns and high-temperature composite components.