Corrosion Behaviour of Collagen Coated and Uncoated Biomedical Titanium Alloy (TNTZ) Within Human Synovial Fluid

Abstract

The corrosion behavior of uncoated Ti-29Nb-13Ta-4.6Zr (TNTZ) and collagen-coated TNTZ within human synovial fluid + NaCl 0.9% solution was investigated using immersion test in order to know the effectivity of collagen to increase bioactivity and also reducing corrosion rate as a coating material. Collagen was selected as coating material because of the ability of adhesion cell and increasing bone healing process. The immersion test has been used as corrosion method due to its simplicity and inexpensive. The immersion time in this study was for 2, 4, and 6 weeks. Surface morphology of material was examined by scanning electron microscope (SEM). Corrosion rate was calculated by measuring degradation of coating mass during the corrosion process. While mechanical property (hardness) of material was measured by microhardness testing. The result of this study showed that collagen coating has reduced the corrosion rate of TNTZ in the human synovial fluid where the corrosion rate of the coated TNTZ is 0.00125 mmpy and the corrosion rate of uncoated one is 0.00262 mmpy after 6 weeks immersion. On the other hand, the hardness of coated TNTZ is higher than the uncoated one. It can be concluded that the collagen coating increases both corrosion resistant and mechanical properties of TNTZ.