An engineered tissue with bioactivity and proper mechanical properties could address the challenge of regenerating damaged tissues. Hydroxyapatite (HA), a ceramic akin to natural bone, is a potential bone substitute. However, its low mechanical strength and minimal degradability in physiological environments limit its effectiveness. This study aims to develop a composite with enhanced mechanical properties and bioactivity for bone regeneration. Accordingly, HA was combined with 13–93B3 borate bioactive glass BG) to form composite powders using solution combustion synthesis (SCS) via two methods, which varied in BG:HA ratios and mixing order. In these methods, pre-prepared particles of one phase are added to the solution of the other phase. The mixture is then placed in the synthesis chamber. A spark plasma intering procedure produced a tablet form of the composites. For comparison, a control tablet with separate BG and HA particles was also prepared. The interface’s connections in control composite were modeled using Material Studio. The final samples were analyzed for physical, mechanical, and biological properties. accordingly, the 75 % HA-containing samples were considered optimal, as they exhibited the highest crystallinity index and the lowest undesirable phase. These samples also showed a particle size range of 30–50 nm, confirming the nanoscale size observed in TEM and PSA results. Also, their FESEM images confirmed the presence of both BG and HA phases. Additionally, the variation in microhardness values, ranging from 68 to 151 Vickers, reflects differences in synthesis methods. Bioactivity was also assessed by immersing samples in simulated body fluid (SBF) over time. After 28 days of immersion, more intense HA peaks, a reduction in Ca2+ and PO4 3− concentrations, and the presence of a P-O band around 1830 cm− 1 indicated the formation of the bone phase. Furthermore, it was confirmed that the mechanical properties can be maintained even after immersion in SBF.

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