scholarly journals Hexagonal Boron Nitride Impregnated Silane Composite Coating for Corrosion Resistance of Magnesium Alloys for Temporary Bioimplant Applications

Metals ◽  
2017 ◽  
Vol 7 (12) ◽  
pp. 518 ◽  
Author(s):  
Saad Al-Saadi ◽  
Parama Chakraborty Banerjee ◽  
M.R. Anisur ◽  
R.K. Singh Raman
Keyword(s):  
Corrosion Resistance ◽  
Boron Nitride ◽  
Composite Coating ◽  
Magnesium Alloys ◽  
Hexagonal Boron Nitride

Corrosion resistance of layer-by-layer assembled polyvinylpyrrolidone/polyacrylic acid and amorphous silica films on AZ31 magnesium alloys

RSC Advances ◽  
2016 ◽  
Vol 6 (68) ◽  
pp. 63107-63116 ◽  
Author(s):  
Lan-Yue Cui ◽  
Rong-Chang Zeng ◽  
Shuo-Qi Li ◽  
Fen Zhang ◽  
En-Hou Han
Keyword(s):  
Corrosion Resistance ◽  
Composite Coating ◽  
Magnesium Alloys ◽  
Amorphous Silica ◽  
Polyacrylic Acid ◽  
Dip Coating ◽  
Mg Alloy ◽  
Layer By Layer ◽  
Silica Films ◽  
Az31 Mg Alloy

A layer-by-layer (LbL)-assembled composite coating containing SiO2 and a biocompatible polyvinylpyrrolidone (PVP) and polyacrylic acid (PAA) multi-layer, designated as SiO2/(PVP/PAA)5, was prepared on AZ31 Mg alloy via dip-coating.

Effect of Boron Nitride on the Mechanical and Electrochemical Properties of Cement Composite

2015 ◽  
Author(s):  
Qinyue He ◽  
Xun Yu
Keyword(s):  
Corrosion Resistance ◽  
Boron Nitride ◽  
Electrochemical Properties ◽  
Hexagonal Boron Nitride ◽  
Water Solution ◽  
Cement Composite ◽  
Sodium Cholate ◽  
Ionic Surfactant ◽  
Cement Composites ◽  
Cement Concrete

Hexagonal boron nitride (h-BN) is well known for its unique properties, such as high thermal conductivity, excellent mechanical strength, high electrical insulating, and high chemical stability. This paper studies the effect of h-BN to the mechanical and electrochemical properties of cement concrete. Sodium cholate is used as an ionic surfactant to exfoliate h-BN and subsequently stabilize them in water solution. Different cement concrete samples with different doping levels of h-BN and different sizes of h-BN were prepared for comparisons. Also, steel fiber reinforced h-BN/cement concrete samples were also prepared. The results show that the addition of h-BN can improve the strength of cement composites, and the degree of reinforcement are influenced by the doping levels and feature size of h-BN. The corrosion resistance of h-BN/cement composites were also tested. Experiments results show that h-BN can enhance the corrosion resistance of cement composites.

scholarly journals Corrosion resistance of monolayer hexagonal boron nitride on copper

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
F. Mahvash ◽  
S. Eissa ◽  
T. Bordjiba ◽  
A. C. Tavares ◽  
T. Szkopek ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Boron Nitride ◽  
Hexagonal Boron Nitride

scholarly journals Construction of Chi(Zn/BMP2)/HA composite coating on AZ31B magnesium alloy surface to improve the corrosion resistance and biocompatibility

2021 ◽  
Vol 10 (1) ◽  
pp. 870-882
Author(s):  
Qiuyang Zhang ◽  
Li Zhang ◽  
Minhui Yang ◽  
Qingxiang Hong ◽  
Zhongmei Yang ◽  
...  
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Composite Coating ◽  
Magnesium Alloys ◽  
Bone Morphogenetic Protein 2 ◽  
Alloy Surface ◽  
Zinc Ions ◽  
Hexadecanoic Acid ◽  
Az31b Magnesium Alloy ◽  
E Coli

Abstract As biodegradable orthopedic implant materials, magnesium alloys have been attracted enough attentions recently. However, too fast degradation in vivo, limited biocompatibilities, and insufficient antibacterial properties are three main challenges at present. In order to solve these problems, a multifunctional composite coating of Chi(Zn/BMP2)/HA was constructed on AZ31B magnesium alloy surface, successively by the alkali heating treatment, self-assembly of 16-phosphonyl-hexadecanoic acid, in situ immobilization of Chi(Zn/BMP2) (chitosan, zinc ions, and bone morphogenetic protein 2), and the deposition of HA (hydroxyapatite). The results of ATR-FTIR (attenuated total reflection Fourier transform infrared spectrum) spectra and elemental compositions confirmed that 16-phosphonyl-hexadecanoic acid, Chi(Zn/BMP2), and HA were successfully immobilized on the surface. Compared with Mg, Mg-OH, Mg-16, and Mg-Chi(Zn/BMP2), Mg-Chi(Zn/BMP2)/HA with the concave–convex structure surface significantly enhanced the hydrophilicity and corrosion resistance. On the other hand, Mg-Chi(Zn/BMP2)/HA coating also showed excellent biocompatibilities, which not only significantly promoted the osteoblast adhesion and proliferation, but also upregulated ALP and OCN expression of osteoblasts. Furthermore, due to the synergistic antibacterial effect of zinc ions and chitosan, Mg-Chi(Zn/BMP2)/HA showed a good antibacterial property against Escherichia coli (E. coli). Therefore, it can be said that the method used in this work has a good application prospect in improving the corrosion resistance, biocompatibility of magnesium alloys, and inhibiting infections against E. coli.

scholarly journals Corrosion Resistance of Modified Hexagonal Boron Nitride (h-BN) Nanosheets Doped Acrylic Acid Coating on Hot-Dip Galvanized Steel

Materials ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2340 ◽  
Author(s):  
Yongzhe Fan ◽  
Huazhen Yang ◽  
Haisheng Fan ◽  
Qi Liu ◽  
Chuang Lv ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Corrosion Resistance ◽  
Boron Nitride ◽  
Acrylic Acid ◽  
Hexagonal Boron Nitride ◽  
Corrosion Current ◽  
Galvanized Steel ◽  
Electrochemical Testing ◽  
Transmission Electron ◽  
Acid Coating

The hexagonal boron nitride (h-BN) nanosheets modified by silane coupling agent (KH560) were doped into acrylic acid coating on the surface of galvanized steel to improve its corrosion resistance. H-BN nanosheets modified by KH560 were prepared and characterised by scanning electron microscopy, transmission electron microscopy, atomic force microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The corrosion resistance of the acrylic acid coatings was measured by electrochemical testing. The results show that the corrosion current density of the coating with modified h-BN nanosheets was reduced from 2.2 × 10−5 A/cm2 to 2.3 × 10−7 A/cm2 compared with the acrylic acid coating. The impedance of the composite coating with modified h-BN is 4435 Ω·cm2, higher than the BNNS coating (2500 Ω·cm2) and the acrylic acid coating (1500 Ω·cm2). This is due to the physical barrier and electrical insulation properties of the hexagonal boron nitride (h-BN) nanosheets.

Effect of Ultrasonic Wave on Ni-P-Al2O3 Electroless Composite Coating on Magnesium Alloy

2011 ◽  
Vol 383-390 ◽  
pp. 953-957 ◽  
Author(s):  
Yong Zhe Fan ◽  
Li Ma ◽  
Xiao Ming Cao
Keyword(s):  
Corrosion Resistance ◽  
Magnesium Alloy ◽  
Composite Coating ◽  
Magnesium Alloys ◽  
Ultrasonic Wave ◽  
Electroless Plating ◽  
Nano Particles ◽  
Ultrasound Wave ◽  
Optimal Conditions ◽  
Coating Hardness

The coating was obtained by electroless plating Ni-P nano Al2O3 on AZ91D magnesium alloys under ultrasound wave. The metallographic microscope and micro sclerometer were used to characterize the structures and hardness of coating. The results showed that in the optimal conditions, ultrasonic electroless plating can increase the coating hardness value by 170HV and extend the coating corrosion resistance time by 130s; inorder to reach the same corrosion resistance time or hardness value, the temperature under ultrasonic decreases 20°C than that without ultrasonic wave; ultrasonic wave can improve the deposition rate, refine the grains and inhibit the nano particles to agglomerate.

Marcus-Hush Theory Revealed by Electron Tunneling Through Hexagonal Boron Nitride

2019 ◽  
Author(s):  
Matěj Velický ◽  
Sheng Hu ◽  
Colin R. Woods ◽  
Peter S. Toth ◽  
Viktor Zólyomi ◽  
...  
Keyword(s):  
Electron Transfer ◽  
Boron Nitride ◽  
Electron Tunneling ◽  
Hexagonal Boron Nitride ◽  
Large Body ◽  
Liquid Solution ◽  
Limiting Current ◽  
Electron Transfer Rate Constant ◽  
Electrochemical Parameters ◽  
Voltammetric Measurements

Marcus-Hush theory of electron transfer is one of the pillars of modern electrochemistry with a large body of supporting experimental evidence presented to date. However, some predictions, such as the electrochemical behavior at microdisk electrodes, remain unverified. Herein, we present a study of electron tunneling across a hexagonal boron nitride barrier between a graphite electrode and redox levels in a liquid solution. This was achieved by the fabrication of microdisk electrodes with a typical diameter of 5 µm. Analysis of voltammetric measurements, using two common redox mediators, yielded several electrochemical parameters, including the electron transfer rate constant, limiting current, and transfer coefficient. They show a significant departure from the Butler-Volmer behavior in a clear manifestation of the Marcus-Hush theory of electron transfer. In addition, our system provides a novel experimental platform, which could be applied to address a number of scientific problems such as identification of reaction mechanisms, surface modification, or long-range electron transfer.

Sign in / Sign up

Export Citation Format

Share Document