Structural characterization, mechanical, and electrochemical studies of hydroxyapatite‐titanium composite coating fabricated using electrophoretic deposition and reaction bonding process

Abstract

In the present work, hydroxyapatite (HA)-titanium (Ti, 20 wt%) composite coating was coated on NiTi alloy substrate by EPD (electrophoretic deposition) process.Before applying the coating, the HA powder was composed with Ti powder using a ball milling process. Influence of the ball milling time on morphology and phase structure of HA-Ti powder was evaluated using TEM and XRD analysis. After composing the HA particles with Ti, the HA-Ti composite powders were coated on the NiTi substrate by the EPD process in an n-butanol medium for 2 min, with the applied voltage of 60 V. XRD and SEM analysis were utilized to evaluate the phase analysis and morphology of the coatings. Mechanical and electrochemical characteristic of the coatings were also assessed using the micro-indentation, micro-scratch, and polarization tests, respectively. The results revealed that the milling process time had a significant influence on reaction bonds and optimum mixing time was 4 hr. Micro-hardness of the HA-Ti composite coating (304 HV) was substantially higher than the HA coating (72 HV). Also, as the HA coating was composed with Ti particles, the amount of force (in the micro-scratch test) required for detaching the coating from the NiTi substrate increased from 7.1 to 17.8 N. The polarization results showed that the HA-Ti composite coating had a higher electrochemical resistance compared with the HA coating. Corrosion resistance of the NiTi alloy coated with HA increased from 133 kΩ. cm 2 to 2,720 kΩ.cm 2 after composed with the Ti particles.

Antibacterial and Cellular Behaviors of Novel Zinc-Doped Hydroxyapatite/Graphene Nanocomposite for Bone Tissue Engineering

“…Furthermore, the phase analysis results (XRD patterns) in Figure 2 show the hexagonal structure for HA nanoparticles (JCPDS 09-432). The ZnHA nanoparticles also show a hexagonal structure like HA [35][36][37][38]. At the same time, compositing the ZnHA nanoparticles with rGO nanosheets did not affect the crystal structure, but a new peak associated with graphene nanosheets (002) appeared [39].…”

Recent Advancements in Surface Modification, Characterization and Functionalization for Enhancing the Biocompatibility and Corrosion Resistance of Biomedical Implants

“…The biological experiments also showed a remarkable enhancement in the formation of bone cells and apatite on the Ti and MWCNT-based HA coatings. Using the EPD method, the same group covered a NiTi alloy substrate with an HA-Ti (Ti, 20 wt.%) composite coating [146]. The HA powder was combined with Ti powder utilizing a ball milling technique before the coating was applied.…”

Apatite Formation Induced by Chitosan/Gelatin Hydrogel Coating Anchored on Poly(aryl ether nitrile ketone) Substrates to Promote Osteoblastic Differentiation

“…[ 6 ] Among them, hydroxyapatite (HA) coating is a biocompatible and osteoconductive strategy for facilitating cellular activities, such as cell proliferation, adhesion, and differentiation. [ 7,8 ] Thus far, various methods, including plasma spraying [ 9 ] and electrochemical deposition, [ 10 ] for preparing HA coating on the surfaces of bone‐implant materials have been investigated. However, there are still limitations regarding implant geometry, bonding strength to the substrate, mechanical property, and the incorporation of the bioactive compounds.…”