Construction novel hydroxyapatite-nitinol nanocomposite for hard tissue applications

Highlights: • Improve the mechanical properties of HA is proposed. • Nitinol has been used in HA ceramic to improve its mechanical reliability. • NHA- NiTi nanocomposites were fabricated by powder metallurgy. • The structural stability of HA phase in HA- NiTi samples and mechanical strength of nanocomposites were studied. Natural Hydroxyapatite (HA)- Nitinol (NiTi) nanocomposites with different percentage of NiTi were fabricated by powder metallurgy. The structural stability of HA phase in HA- NiTi samples and mechanical strength of nanocomposites were studied by FTIR, XRD and compression test. In addition, biological behavior of the composites were investigated by in vitro studies. The existence of NiTi metal phase can promote dehydration and decomposition of HA ceramic phase into more stable calcium phosphate phases at high temperatures. According to results that obtained, the nanocomposite sample with 10 wt% NiTi has the maximum compressive strength (67.67 MPa) compare to pure HA ceramic (46 MPa) that manufactured under the same condition. Crack deflection is the chief strength mechanism in the nanocomposites. in vitro studies showed that MG-67 osteoblast cells attached and spread on the surface of the sample. The results revealed that nanocomposite with 10 wt% NiTi has a good mechanical strength and suitable biological behavior that can be used in medical applications.