Study of the calcium phosphate layer grown on AISI 316 stainless steel from a simulated body fluid

A calcium phosphate layer was deposited on the surface of AISI 316 stainless steel by immersion in a solution, supersaturated for calcium and phosphorous ions. The substrates were pre-modified by ion implantation of Ca and P in order to induce nuclei for calcium phosphate growth on the surface. The reactivity of these surfaces towards crystal growth in aqueous solution was examined by Fourier Transform Infrared Spectroscopy, Raman Spectroscopy, Scanning Electron Microscopy and Energy Dispersive X-ray Spectroscopy. They showed that the deposited layer was a mixture of hydroxyapatite and other calcium phosphates.