Auger Spectroscopic Analysis of Bioglass Corrosion Films

Auger spectroscopy and ion beam milling were used to determine surface compositional profiles on a series of bioglass implant materials after exposure to simulated body conditions. Four glasses were examined, a soda‐lime‐silica glass and 3 compositions produced by adding 3, 6, and 12 wt% P₂O₅ to the ternary glass. An SiO₂‐rich layer is formed on the surface of all glasses investigated. As P₂O₅ is added to the bulk composition, a second film rich in Ca and P forms at the SiO₂‐rich film‐water interface. The rate of formation of the Ca‐P film increases as the P₂O₅ content of the bulk glass increases. When glasses are corroded under identical conditions, the thickness of the Ca‐P layer increases as the P₂O₅ content of the bulk composition is increased.