Corrosion behaviour of some selected bioglasses by different aqueous solutions

Corrosion studies of some selected bioglasses were carried out using the grain method. This investigation includes the study of the effect of varying the glass composition, leaching solution and duration of the immersion in the respective solution. Experimental results indicate that the it,eight loss changed depending on the type of oxide introduced: B2O3, Al2O3, AlgO, ZnO and the ability of such oxides to strengthen the structure of the bioglasses. The corrosion weight loss was found to vary with the nature of leaching solution and showed the highest corrosion with sodium phosphate solution similar to56% in Hench's bioglass and the lowest with sodium hydroxide solution and the other leaching solutions were found to increase the corrosion weight loss. The introduction of 5 wt% B2O3 content in the glass decreases the corrosion towards the sodium phosphate solution while the glass with 15 wt% B2O3 shows the highest loss of similar to87%. Interpretation of the results was based on the current views about the corrosion mechanism in bioglasses. The behaviour of such bioglasses was found to be different from traditional industrial soda-lime silica glasses. The effects of various factors were evaluated and correlated with the ability of the studied oxide to promote or retard the corrosion mechanism.