A novel approach to enhance mechanical properties of Ti substrates for biomedical applications

The present study proposes a novel approach to flat rolling in order to improve the mechanical properties of pure Ti substrates, making it a promising alternative to the Ti-6Al-4V alloy commonly used in biomedicine. Commercially pure titanium grade 4 (TiG4) was subjected to a process of multi -rotational flat rolling (MRFR) that resulted in a refinement of the microstructure and an improvement in microhardness up to values comparable to those of the titanium alloy Ti-6Al-4V. The biggest advantage of the MRFR processing performed was that it maintained the square cross-section of the titanium product, which gives the possibility of fabricating relatively large products with improved mechanical properties for biomedical applications. The objective of this research was to compare TiG4 after MRFR processing with TiG5 (Ti-6Al-4V) to assess the influence of the processing on the properties of pure titanium. The products obtained were characterized in microstructure and chemical composition, wettability, surface energy, roughness, and stiffness; by using light microscopy, scanning electron microscopy equipped with energy dispersive spectroscopy, contact angle measurements, optical profilometry, and atomic force microscopy. Bacterial and cell tests were conducted to consider the potential of the proposed methodology in biomedical applications. To this end, corrosion tests in Hank's solution were performed to simulate the conditions in the peri-implant environment.