Surface characteristics and corrosion resistance of spangle on hot-dip galvanized coating

Micro arc oxidation (MAO) is a prominent surface treatment to form bioceramic coating layers with beneficial physical, chemical, and biological properties on the metal substrates for biomaterial applications. In this study, MAO treatment has been performed to modify the surface characteristics of AZ31 Mg alloy to enhance the biocompatibility and corrosion resistance for implant applications by using an electrolytic mixture of Ca3(PO4)2 and C10H16N2O8 (EDTA) in the solutions. For this purpose, the calcium phosphate (Ca-P) containing thin film was successfully fabricated on the surface of the implant material. After in-vivo implantation into the rabbit bone for four weeks, the apparent growth of soft tissues and bone healing effects have been documented. The morphology, microstructure, chemical composition, and phase structures of the coating were identified by SEM, XPS, and XRD. The corrosion resistance of the coating was analyzed by polarization and salt spray test. The coatings consist of Ca-P compounds continuously have proliferation activity and show better corrosion resistance and lower roughness in comparison to mere MAO coated AZ31. The corrosion current density decreased to approximately 2.81 × 10−7 A/cm2 and roughness was reduced to 0.622 μm. Thus, based on the results, it was anticipated that the development of degradable materials and implants would be feasible using this method. This study aims to fabricate MAO coatings for orthopedic magnesium implants that can enhance bioactivity, biocompatibility, and prevent additional surgery and implant-related infections to be used in clinical applications.

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Composition―Nanostructure Steered Performance Predictions in Steel Wires

Nanomaterials ◽

10.3390/nano9081119 ◽

2019 ◽

Vol 9 (8) ◽

pp. 1119 ◽

Cited By ~ 1

Author(s):

Kun V. Tian ◽

Francesca Passaretti ◽

Adelaide Nespoli ◽

Ernesto Placidi ◽

Roberta Condò ◽

...

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Bulk Composition ◽

Surface Characteristics ◽

Martensite Phase ◽

Detection Sensitivity ◽

Martensite Content ◽

Austenite Stability ◽

Strain Induced Martensite ◽

Metastable Austenitic Stainless Steel

Neutron scattering in combination with scanning electron and atomic force microscopy were employed to quantitatively resolve elemental composition, nano- through meso- to metallurgical structures and surface characteristics of two commercial stainless steel orthodontic archwires—G&H and Azdent. The obtained bulk composition confirmed that both samples are made of metastable austenitic stainless steel type AISI 304. The neutron technique’s higher detection sensitivity to alloying elements facilitated the quantitative determination of the composition factor (CF), and the pitting resistance equivalent number (PREN) for predicting austenite stability and pitting-corrosion resistance, respectively. Simultaneous neutron diffraction analyses revealed that both samples contained additional martensite phase due to strain-induced martensite transformation. The unexpectedly high martensite content (46.20 vol%) in G&H was caused by combination of lower austenite stability (CF = 17.37, p = .03), excessive cold working and inadequate thermal treatment during material processing. Together, those results assist in revealing alloying recipes and processing history, and relating these with corrosion resistance and mechanical properties. The present methodology has allowed access to unprecedented length-scale (μm to sub-nm) resolution, accessing nano- through meso-scopic properties. It is envisaged that such an approach can be extended to the study and design of other metallic (bio)materials used in medical sciences, dentistry and beyond.

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THE HOT‐DIP GALVANIZED COATING AND CORROSION RESISTANCE: Part 2

Anti-Corrosion Methods and Materials ◽

10.1108/eb019640 ◽

1959 ◽

Vol 6 (10) ◽

pp. 307-309

Author(s):

John H. Nicholls

Keyword(s):

Corrosion Resistance ◽

Galvanized Coating

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Application of Oxygen Ion Implantation to Titanium Surfaces: Effects on Surface Characteristics, Corrosion Resistance, and Bone Response

Clinical Implant Dentistry and Related Research ◽

10.1111/j.1708-8208.2001.tb00144.x ◽

2001 ◽

Vol 3 (4) ◽

pp. 221-229 ◽

Cited By ~ 28

Author(s):

Takashi Sawase ◽

Ann Wennerberg ◽

Koumei Baba ◽

Yoichi Tsuboi ◽

Lars Sennerby ◽

...

Keyword(s):

Corrosion Resistance ◽

Ion Implantation ◽

Surface Characteristics ◽

Oxygen Ion ◽

Bone Response ◽

Titanium Surfaces ◽

Oxygen Ion Implantation

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Effect of Bismuth on the Microstructure and Corrosion Resistance of Galvanized Coating

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.391-392.1183 ◽

2011 ◽

Vol 391-392 ◽

pp. 1183-1188 ◽

Cited By ~ 1

Author(s):

Jian Hua Wang ◽

Xing Ming Wang ◽

Chun Mei Liu ◽

Xu Ping Su ◽

Chang Jun Wu ◽

...

Keyword(s):

Corrosion Resistance ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Electrochemical Corrosion ◽

Energy Dispersive ◽

Phase Layer ◽

Corrosion Tests ◽

X Ray ◽

Galvanized Coating ◽

Scanning Electron

The microstructure of the galvanized coating was investigated using scanning electron microscope equipped with energy dispersive X-ray spectroscope. The immersing and electrochemical corrosion tests were carried out to study the corrosion resistance of the galvanized coating. The addition of Bi in Zn-bath affects remarkably the morphology of the galvanized coating. The thickness of δ + ζ phase layer in the coating reaches the maximum when the content of Bi in Zn-bath is 0.5 wt.%. The corrosion resistance of the galvanized coating declines with the increase of the content of Bi.

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Surface characteristics and corrosion resistance properties of TiNi shape memory alloy coated with Ta

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2004.01.012 ◽

2004 ◽

Vol 186 (3) ◽

pp. 346-352 ◽

Cited By ~ 42

Author(s):

Y. Cheng ◽

W. Cai ◽

H.T. Li ◽

Y.F. Zheng ◽

L.C. Zhao

Keyword(s):

Corrosion Resistance ◽

Shape Memory Alloy ◽

Shape Memory ◽

Surface Characteristics

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Corrosion resistance of surface modified nickel titanium archwires

The Angle Orthodontist ◽

10.2319/021813-140.1 ◽

2013 ◽

Vol 84 (2) ◽

pp. 358-367 ◽

Cited By ~ 8

Author(s):

Manu Krishnan ◽

Saraswathy Seema ◽

A. Vinod Kumar ◽

N. Parvatha Varthini ◽

Kalathil Sukumaran ◽

...

Keyword(s):

Surface Roughness ◽

Corrosion Resistance ◽

Surface Characteristics ◽

Group 4 ◽

Group 3 ◽

Group 5 ◽

Group 2 ◽

Surface Modified ◽

Niti Wires ◽

Group 1

ABSTRACT Objective: To compare the corrosion behavior of commercially available surface modified nickel titanium (NiTi) arch wires with respect to a conventional NiTi and to evaluate its association with surface characteristics. Materials and Methods: Five types of surface modified arch wires and a conventional NiTi arch wire, all from different manufacturers, were evaluated for their corrosion resistance from breakdown potential in an anodic polarization scan in Ringer's solution. Surface characteristics were determined from scanning electron microscopy, atomic force microscopy, and energy dispersive analysis. One-way analysis of variance and post hoc Duncan's multiple range tests were used to evaluate statistical significance. Results: Surface modified NiTi wires showed significant improvement in corrosion resistance and reduction in surface roughness values. Breakdown potentials increased in the order of group 6 (conventional; 204 mV) < group 1 (nitride; 333 mV) < group 5 (epoxy resin; 346mV) < group 3 (oxide; 523 mV) < group 2 (gold; 872 mV) < group 4 (Teflon; 1181 mV), but root mean square (RMS) roughness values, which indicated surface roughness, followed a different pattern: group 3 (oxide; 74.12 nm) < group 1 (nitride; 221.651 nm) < group 4 (Teflon; 278.523 nm) < group 2 (gold; 317.894 nm) < group 5 (epoxy resin; 344.236 nm) < group 6 (conventional; 578.555 nm). Conclusions: Surface modification of NiTi wires proved to be effective in improving its corrosion resistance and decreasing surface roughness. However, neither factor could maintain a direct, one-to-one relationship. It meant that the type and nature of coating material can effectively influence the anticorrosive features of NiTi wires, compared with its surface roughness values.

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Corrosion Susceptibility of Surface Etched Ultrafine Grained Titanium and its Alloys under Physiological Environment

10.20944/preprints201807.0464.v1 ◽

2018 ◽

Author(s):

Daniel Fernandes ◽

Egor Prokofiev ◽

Ruslan Valiev ◽

Ana Almeida ◽

Emilia Monteiro ◽

...

Keyword(s):

Corrosion Resistance ◽

Polarization Resistance ◽

Surface Characteristics ◽

Coarse Grained ◽

Native Oxide ◽

Native Oxide Layer ◽

Surface Etching ◽

Ultrafine Grained ◽

Corrosion Susceptibility ◽

Titanium Grade

1) Background: The objective was to evaluate the corrosion resistance of different commercially pure ultrafine-grained (UFG) titanium and its alloys with acid etched surface processed by equal-channel angular pressing (ECAP); 2) Methods: Coarse-grained and UFG titanium samples were investigated using polarization resistance technique. Surface characteristics of the native oxidized layer were evaluated by TEM and XRD. Electrochemical tests were under physiological electrolyte at a rate of 1 and 10 mV/s. Weight loss tests were performed after immersion into HCl solution for up to 3 years;   3) Results: UFG titanium was less susceptible to corrosion which was identified under lower rates and at higher polarization resistance than its coarse grain counterparts. Titanium Grade 2 and Grade 4 demonstrated similar corrosion susceptibility. Titanium Grade 5 revealed a thin and tightly adhered native oxide layer with adequate corrosion resistance; 4) Conclusions: ECAP process imposed a more compact and adhered oxidized layer. Surface etching techniques delivered a thicker native TiO2 layer, being both grain refinement and surface etching techniques responsible for the improved corrosion resistance of Titanium samples under physiological environment after 3 years of observation.

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