Research on wear and high cycle fatigue performance of ceramic coatings produced on Ti-6Al-4V alloy by micro-arc oxidation

Abstract

Ceramic coatings were produced on the surface of Ti-6Al-4V titanium alloy by Micro-Arc Oxidation (MAO) technique. The morphology and phases of coatings were investigated by scanning electron microscopy (SEM), and X-ray diffraction (XRD) technologies. The friction and high cycle fatigue properties were tested in coated and uncoated specimens. The results show that the MAO coatings were mainly composed of the anatase TiO2 phase, which grows in-suit on the surface of the substrate material. There was no transition layer between the coatings and the substrate, and a high bonding strength was obtained. The anti-abrasion properties of the coated specimens were improved because of the high hardness of ceramic coatings. MAO generates many micro-pores. During fatigue loading, the micropores act as notches to cause stress concentration, which can decrease the fatigue life of substrate material.