Tribo-Corrosion and Corrosion Behaviour of Titanium Alloys with and Without DLC Films Immersed in Synthetic Urine

Abstract

Nowadays, potable water is becoming scarcer, and chemicals components present in wastewater increase corrosion of devices and decrease its lifespan, especially from bearings used in water recovery system. The bearings are subjected to severe corrosion due to harsh environmental conditions from urine composition. 60NiTi alloy which was developed to attend International space station requirements as a resistant material to recycle wastewater to potable water, together DLC film as a solid lubricant, could be new protective material to avoid tribo-corrosion and corrosion from devices under hostile environment. In this work, we compared the tribocorrosion resistance of 60NiTi, also named as NiTi60T and thermally treated, and Ti–6Al–4V alloys with and without diamond-like carbon (DLC) film. The NiTi60T is a promising candidate to be used for the centrifuge bearings to expand their lifespan when in contact with synthetic urine. The DLC film presented high levels of wear resistance, metallic adhesion, and corrosion protection for both tested alloys.