Obtaining a nanoporous layer by the anodizing process on AISI 316L steel to obtain better corrosion resistance properties in metallic biomaterials applications

Abstract

AISI 316L is a metallic biomaterial used in Unified Health System (SUS) due to low cost. However, corrosion in AISI 316L is a major cause of premature failure and toxic reactions to implants. Nanotubular or nanoporous anodized layers have proven to be good and affordable alternatives to create greater interaction and less damage to human tissue. Thus, the main of this study was to obtain a nanoporous layer by anodizing on AISI 316L, aiming to improve its corrosion resistance for use as a biomaterial. AISI 316L were anodized in 10M NaOH, 0.6mA/cm2 for 5 and 10min. Transients of current density and potential and oxide color were evaluated. Anodized layers were characterized by scanning electron microscopy, X-ray diffraction analysis and electrochemical assays. Nanoporous anodized layers with nanoplate arrangement were obtained. The 5min anodized sample showed better corrosion resistance than the original steel, being considered promising for use as a biomaterial.