Powder-Metallurgy Mg/45S5 Bioglass Composites for Biomedical Applications

This study investigates magnesium-based composites reinforced with 45S5 bioactive glass (BG) at 2.5 and 5[Formula: see text]wt.% using the powder metallurgy method. The effects of BG content on microstructure, density, hardness, wear, and corrosion behavior were examined. XRD and SEM analyses showed a uniform BG distribution at 2.5[Formula: see text]wt.% but agglomeration at 5[Formula: see text]wt.%. The addition of 2.5[Formula: see text]wt.% BG increased hardness by about 4.6% (from 52.7 to 55.1 HBW) due to dispersion strengthening and the intrinsic properties of the silicate-rich BG phase, whereas 5 wt.% BG caused a 9.5% decrease compared to pure Mg (down to 47.7 HBW) due to particle clustering. Wear resistance also improved at 2.5[Formula: see text]wt.% BG, reducing wear rate under 10[Formula: see text]N load by about 11.9% (from 0.0185 to 0.0163[Formula: see text]mm 3 /m). However, at 5[Formula: see text]wt.% BG, the wear rate rose again to 0.0176[Formula: see text]mm 3 /m, reflecting the adverse effect of agglomeration. The density followed a similar trend, increasing by 4.2% at 2.5[Formula: see text]wt.% BG but then declining at 5[Formula: see text]wt.% BG. Corrosion resistance improved markedly at 2.5[Formula: see text]wt.% BG, with the corrosion rate dropping from 2.37 to 0.80[Formula: see text]mm/year, whereas 5[Formula: see text]wt.% BG led to a sharp increase to 5.34[Formula: see text]mm/year. Overall, the 2.5[Formula: see text]wt.% BG composite achieved the most favorable balance of hardness, wear resistance, and corrosion performance, making it a promising candidate for biomedical load-bearing applications.