Study on properties and biocompatibility of ZrO2/Ti composites prepared by selective laser melting

At present, problems such as unsatisfactory strength, hardness, and poor wear resistance seriously restrict the development of pure titanium in orthopedic implants. In this study, ZrO
₂
/Ti composite material with ZrO
₂
contents of 0 wt%, 1 wt%, 3 wt%, and 5 wt% were successfully prepared by selective laser melting technology. The mechanical properties and biocompatibility of the forming samples were tested. The experimental results showed that the mechanical properties of ZrO
₂
/Ti composite material were significantly improved with ZrO
₂
added. Compared with other contents of ZrO
₂
, composite material with 5 wt% ZrO
₂
achieved the greatest enhancement of mechanical properties. Its compressive strength and average microhardness were 1424 MPa and 464 HV, respectively, which were about twice of that for the pure titanium samples. Corrosion resistance was also improved. In addition, the friction coefficient of 5 wt% content ZrO
₂
/Ti composite material was 0.426, which was much lower than the pure titanium sample (0.604). Besides, the cell test proved that the samples had good biocompatibility and no cytotoxicity, which indicated that the addition of zirconia had no damage effect on the growth of osteoblasts.