Microwave-assisted irradiation crystallization of 45S5 bioglass: Densification, mechanical performance, microstructure evolution, and multifunctional bio-performance

In recent times, 45S5 bioglass-ceramics have attracted significant attention for biomedical applications due to their excellent mechanical performance and considerable bioactivity. In this study, 45S5 bioglass was fabricated by a melt-quenching method and subjected to microwave-assisted sintering at temperatures ranging from 850 to 1050°C to evaluate the influence of thermal treatment on densification, mechanical properties, structural evolution, bioactivity, and antibacterial performance. The findings indicate that microwave-assisted crystallization noticeably enhanced the densification and mechanical properties of the 45S5 bioglass. The micro-hardness increased from 7.45 ± 0.03 GPa to 12.69 ± 0.03 GPa, while the bulk density increased from 2.63 ± 0.03 g/cm 3 at 850°C to 4.67 ± 0.02 g/cm³ at 1050°C. Likewise, as the sintering temperature rose, the compressive strength rose from 72.35 ± 0.04 MPa to 120.55 ± 0.03 MPa. While SEM observations and in vitro simulated body fluid (SBF) immersion demonstrated the formation of a dense hydroxycarbonate (HCA) apatite layer, XRD examination revealed the existence of crystalline combeite and wollastonite phases. The bioglass-ceramics also demonstrated antibacterial activity against the tested pathogens indicated with increasing zone of inhibition at rising sintering temperature. A one-way ANOVA revealed that the sintered groups' differences were statistically significant (p < 0.001), as the sintering temperature increased. The developed materials exhibited promising potential for biomedical applications, particularly in bone repair and regeneration.