Study of the effect of ZnO nanoparticles addition to PEO coatings on pure titanium substrate: Microstructural analysis, antibacterial effect and corrosion behavior of coatings in Ringer's physiological solution

Hydroxyapatite (HA) is a very common material used for biomedical applications. Usually, in order to improve its poor mechanical properties is combined or coated with other high-strength materials.The present paper reports the manufacturing and the biocompatibility behaviour of two different biocomposite coatings consisting of alumina (Al2O3) and hydroxyapatite (HA) using the high velocity oxygen fuel (HVOF) spraying method which were deposited onto the surface of a commercially pure titanium substrate. The biological properties of the Al2O3-HA materials were evaluated by in vitro studies. The morphology of the coatings before and after their immersing in the simulated body fluid (SBF) solution was characterized by scanning electron microscopy (SEM). The results showed an important germination of the biologic hydroxyapatite crystallite on the surface of both coatings.

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Microstructural Analysis of Fractured Orthopedic Implants

Materials ◽

10.3390/ma14092209 ◽

2021 ◽

Vol 14 (9) ◽

pp. 2209

Author(s):

Mateusz Kopec ◽

Adam Brodecki ◽

Grzegorz Szczęsny ◽

Zbigniew L. Kowalewski

Keyword(s):

Physical Activity ◽

Electron Microscopy ◽

Scanning Electron Microscopy ◽

Fracture Behavior ◽

Locking Plate ◽

Microstructural Analysis ◽

Pure Titanium ◽

Orthopedic Implants ◽

Mechanical Loads ◽

Scanning Electron

In this paper, fracture behavior of four types of implants with different geometries (pure titanium locking plate, pure titanium femoral implant, Ti-6Al-4V titanium alloy pelvic implant, X2CrNiMo18 14-3 steel femoral implant) was studied in detail. Each implant fractured in the human body. The scanning electron microscopy (SEM) was used to determine the potential cause of implants fracture. It was found that the implants fracture mainly occurred in consequence of mechanical overloads resulting from repetitive, prohibited excessive limb loads or singular, un-intendent, secondary injures. Among many possible loading types, the implants were subjected to an excessive fatigue loads with additional interactions caused by screws that were mounted in their threaded holes. The results of this work enable to conclude that the design of orthopedic implants is not fully sufficient to transduce mechanical loads acting over them due to an increasing weight of treated patients and much higher their physical activity.

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Comparison of Biocompatible Coatings Produced by Plasma Electrolytic Oxidation on cp-Ti and Ti-Zr-Nb Superelastic Alloy

Coatings ◽

10.3390/coatings11040401 ◽

2021 ◽

Vol 11 (4) ◽

pp. 401

Author(s):

Ruzil Farrakhov ◽

Olga Melnichuk ◽

Evgeny Parfenov ◽

Veta Mukaeva ◽

Arseniy Raab ◽

...

Keyword(s):

Plasma Electrolytic Oxidation ◽

Electrochemical Impedance ◽

Pure Titanium ◽

Commercially Pure Titanium ◽

X Ray ◽

Kinetic Coefficients ◽

Electrolytic Oxidation ◽

Plasma Electrolytic ◽

Cp Ti ◽

Peo Coatings

The paper compares the coatings produced by plasma electrolytic oxidation (PEO) on commercially pure titanium and a novel superelastic alloy Ti-18Zr-15Nb (at. %) for implant applications. The PEO coatings were produced on both alloys in the identical pulsed bipolar regime. The properties of the coatings were examined using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy-dispersive X-ray spectroscopy (EDX), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). The PEO process kinetics was modeled based on the Avrami theorem and Cottrell equation using a relaxation method. The resultant coatings contain TiO2, for both alloys, and NbO2, Nb2O5, ZrO2 for Ti-18Zr-15Nb alloy. The coating on the Ti-18Zr-15Nb alloy has a higher thickness, porosity, and roughness compared to that on cp-Ti. The values of the kinetic coefficients of the PEO process—higher diffusion coefficient and lower time constant for the processing of Ti-18Zr-15Nb—explain this effect. According to the electrochemical studies, PEO coatings on Ti-18Zr-15Nb alloy provide better corrosion protection. Higher corrosion resistance, porosity, and roughness contribute to better biocompatibility of the PEO coating on Ti-18Zr-15Nb alloy compared to cp-Ti.

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Chemical Composition and Corrosion Behavior of a-C:H/DLC Film-Coated Titanium Substrate in Simulated PEMFC Environment

Coatings ◽

10.3390/coatings11070820 ◽

2021 ◽

Vol 11 (7) ◽

pp. 820

Author(s):

Beibei Han ◽

Mengyuan Yan ◽

Dongying Ju ◽

Maorong Chai ◽

Susumu Sato

Keyword(s):

Corrosion Resistance ◽

Corrosion Behavior ◽

Metal Ion ◽

Ion Beam ◽

Titanium Substrate ◽

Corrosion Current ◽

Ion Concentration ◽

Bipolar Plates ◽

High Adhesion ◽

Corrosion Behaviors

The amorphous hydrogenated (a-C:H) film-coated titanium, using different CH4/H2 and deposition times, was prepared by the ion beam deposition (IBD) method, which has the advantage of high adhesion because of the graded interface mixes at the atomic level. The chemical characterizations and corrosion behaviors of a-C:H film were investigated and evaluated by SEM, AFM, Raman spectroscopy, EPMA, TEM and XPS. An a-C:H film-coated titanium was corroded at 0.8 V, 90 °C in a 0.5 mol/L H2SO4 solution for 168 h. The metal ion concentration in the H2SO4 corrosion solution and the potentiodynamic polarization behavior were evaluated. Results indicate that a higher CH4/H2 of 1:0 and a deposition time of 12 h can result in a minimum ID/IG ratio of 0.827, Ra of 5.76 nm, metal ion concentration of 0.34 ppm in the corrosion solution and a corrosion current of 0.23 µA/cm2. The current density in this work meets the DOE’s 2020 target of 1 µA/cm2. Electrical conductivity is inversely proportional to the corrosion resistance. The significant improvement in the corrosion resistance of the a-C:H film was mainly attributed to the increased sp3 element and nanocrystalline TiC phase in the penetration layer. As a result, the a-C:H film-coated titanium at CH4/H2 = 1:0 with improved anti-corrosion behavior creates a great potential for PEMFC bipolar plates.

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Sliding Wear Behavior of Remelted Al2O3-TiO2 Plasma Sprayed Coatings on Titanium

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.254.231 ◽

2016 ◽

Vol 254 ◽

pp. 231-236 ◽

Cited By ~ 1

Author(s):

Ion Dragoş Uţu ◽

Gabriela Marginean ◽

Iosif Hulka ◽

Viorel Aurel Şerban

Keyword(s):

Sliding Wear ◽

Wear Behavior ◽

Pure Titanium ◽

Titanium Substrate ◽

Atmospheric Plasma ◽

Wear Properties ◽

Before And After ◽

Sprayed Coating ◽

Pin On Disk ◽

Sprayed Coatings

Microstructure and wear properties of the Al2O3-13.wt% TiO2 thermally sprayed coatings before and after remelting were investigated in this study. The coatings were deposited on a pure titanium substrate using the atmospheric plasma spraying (APS) process. The as-sprayed coatings were electron beam (EB) modified in order to improve their compactness and bonding strength.The effect of EB remelting on the microstructure, phase constituents and wear properties was investigated using scanning electron microscopy (SEM), X-Ray diffraction technique and hardness measurements. The sliding wear behavior was tested using a pin on disk method.The results showed that the remelting process had a positive effect removing the lamellar defect of the as-sprayed coating and improving the compactness, hardness and wear behavior.

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Antibacterial effect of chronic exposure of low concentration ZnO nanoparticles onE. coli

Journal of Environmental Science and Health Part A ◽

10.1080/10934529.2013.761489 ◽

2013 ◽

Vol 48 (8) ◽

pp. 871-878 ◽

Cited By ~ 23

Author(s):

R.K. Dutta ◽

Bhavani P. Nenavathu ◽

Mahesh K. Gangishetty ◽

A.V.R. Reddy

Keyword(s):

Zno Nanoparticles ◽

Chronic Exposure ◽

Antibacterial Effect ◽

Low Concentration

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Solidification in Laser Cladding of a Ti-Si Graded Coating on Pure Titanium Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.739.196 ◽

2013 ◽

Vol 739 ◽

pp. 196-200 ◽

Cited By ~ 1

Author(s):

T.M. Yue ◽

K.J. Huang ◽

H. Xie

Keyword(s):

Laser Cladding ◽

Solid Solutions ◽

Silicon Content ◽

Pure Titanium ◽

Titanium Substrate ◽

Eutectic Growth ◽

Commercially Pure Titanium ◽

Commercially Pure ◽

Graded Coating

A three-layer Ti-Si graded coating was fabricated on a commercially pure titanium substrate by laser cladding with Ti-5.8 at%Si, Ti-9.0 at%Si and Ti-13.5 at%Si mixed powders. The microstructure of the three layers comprised Ti-Si solid solutions (Ti) and the Ti5Si3 compound. As the silicon content was increased, the microstructure along the direction of deposition underwent a series of changes, including replacement of the (Ti) phase by the primary Ti5Si3 phase, and a change of the (Ti)/Ti5Si3 eutectic growth from lamellar to anomalous.

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