Mechanism of a novel Si/B erosion-reducing additive for extending gun barrel lifespan

Erosion and wear generated during gun firing can damage the bore surface of gun barrels and shorten their service life. The use of erosion-reducing additives in gun propellant charges can effectively mitigate these adverse effects. Against this background, this study focuses on a novel Si/B erosion-reducing additive and investigates its mechanism in reducing erosion and wear. First, the lifespan-extending effectiveness of the additive was evaluated through simulated firing experiments. Subsequently, the microscopic morphology of the adhesive layers formed on the inner walls of the simulated tubes was analyzed using SEM. The chemical composition of these layers was further characterized through FT-IR, 1 H NMR, XRD, and EDS analyses. The results show that the Si/B additive decomposes and liquefies at high temperatures, forming a wavy adhesive layer on the inner wall with an average thickness of 5–5.5 µm. This layer is composed of B₂O₃ and SiO₂, with B₂O₃ being the dominant component. Due to its lower thermal conductivity and its ability to form a thicker adhesive layer, B 2 O 3 effectively prevents high-temperature heat flow from transferring to the inner wall. Additionally, compared with TiO 2 and talc, B 2 O 3 has a lower melting point and liquefies rapidly, enabling it to repair cracks on the bore surface. Therefore, materials with low melting points and low thermal conductivity show strong potential for use as components in erosion-reducing additives. • Developed a novel erosion-reducing additive composed of α,ω-dihydroxy polydimethylsiloxane and B 2 O 3 . • B 2 O 3 forms a 5–5.5-μm protective layer on the inner wall, effectively preventing gun barrel erosion. • Low-melting-point materials with low thermal conductivity can serve as effective erosion inhibitors.