Research Progress Regarding Interfacial Characteristics and the Strengthening Mechanisms of Titanium Alloy/Hydroxyapatite Composites

Abstract

Titanium alloy/Hydroxyapatite (HA) composites have become a hot research topic in biomedical materials, while there are some challenges concerning bioactivity and mechanical properties such as low interface adhesion at the interface between metal and ceramic, complex interfacial reactions, and so on. Nevertheless, composites with reinforced phases can reach special properties that meet the requirements of biomedical materials due to the strong interfacial interactions between reinforcing phases (nano-carbon, partial oxides, and so on) and Titanium alloys or HA. This review summarizes the interface properties and mechanisms of Titanium alloy/HA composites, including interfacial bonding methods, strengthening and toughening mechanisms, and performance evaluation. On this basis, the interface characteristics and mechanisms of the Titaniumalloy/HA composites with enhanced phase are prospected. The results show that the interfacial bonding methods in the Titanium alloy/HA composites include chemical reactions and mechanical effects. The strengthening and toughening mechanisms contain grain refinement strengthening, second phase strengthening, solution strengthening, cracks and pulling out mechanisms, etc. This review provides a guidline for the fabrication of biocomposites with both mechanical properties and bioactivity.

Properties and Mechanism of Hydroxyapatite Coating Prepared by Electrodeposition on a Braid for Biodegradable Bone Scaffolds

“…Compared to the standard cell parameters of HA crystals according to the ICDD database diffraction file #09-0432, the value of the calculated c (Å) of HA crystals prepared by electrodeposition slightly increases, and a slight decrement of a (Å)/b (Å) is detected. Moreover, with the increase of deposition time from 60 min to 120 min, the unit cell parameter a (Å)/b (Å) decreases first and then increases, while the value of c (Å) increases first and then decreases [39].…”

Interfacial Oxidized Gate Insulators for Low-Power Oxide Thin-Film Transistors

“…When the whole area is covered by anodic oxide, the anodic currents decrease rapidly, and then the electric breakdown of the weakly bonded area occurs, which increases the anodic current again. The experimental results show that anodic oxidation and electric breakdown occurred irregularly, as shown in Figure a …”

“…The experimental results show that anodic oxidation and electric breakdown occurred irregularly, as shown in Figure 3a. 50 The fluctuation of the anodic currents was resolved by preannealing. Before anodic oxidation, thermal interfacial oxidation was performed by furnace annealing at 300 °C for 1 h. Preannealing improved the anodic oxidation process without fluctuation of the anodic currents, as shown in Figure 4a.…”

Microstructure and Mechanical Properties of Titanium–Equine Bone Biocomposites

“…In order to give high osteoconductive property to Ti6Al4V alloy, calcium phosphate-based ceramics such as hydroxyapatite are also coated by plasma spraying [16]. Especially hydroxyapatite has high biocompatibility, bioactivity, osteoconductive property, and osteoinduction, since a lot of researchers have released results of biomaterials containing hydroxyapatite [13,15,[17][18][19][20][21][22]. Meanwhile, biomaterials containing calcium phosphate (Ca 3 (PO 4 ) 2 ) from biological wastes such as pig bones, fish bones, and horse bones have been used as raw materials for mass production of natural hydroxyapatite at low cost, according to recent reports [23][24][25].…”