Preparation and Performance of Ceramic Coatings Formed by Micro Arc Oxidation on Titanium Alloy

2008 ◽  
Vol 375-376 ◽  
pp. 323-327
Author(s):  
Ying Xue Yao ◽  
Li Qun Li ◽  
Jian Jun Xi
Keyword(s):  
Titanium Alloy ◽  
Ceramic Coating ◽  
Ceramic Coatings ◽  
Dense Layer ◽  
X Ray Diffraction ◽  
Technological Parameters ◽  
Tc4 Titanium Alloy ◽  
Micro Arc Oxidation ◽  
Anodic Voltage ◽  
And Performance

The effect of technological parameters on MAO ceramic coating were investigated through the technique of micro-arc oxidation (MAO) on TC4 titanium alloy and. Microstructure and morphology of coatings were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The result shows that electric parameters and compositions of the electrolyte have notable effects on the growth of MAO ceramic coatings. The cathodic and anodic voltage rise gradually with the oxidation time increasing. The growth rate of ceramic coating is fast at the beginning, and then turns slowly. The ceramic coatings can be divided into three layers from interior to exterior, such as the transition layer, the dense layer and the porous layer. The coating is mainly composed of rutile and anatase and combined with the substrate firmly. The ceramic coating’s composition in inner and outer layers appears quite different. The ceramic coating on titanium alloy is of excellent performance on anti-attrition and anti-corrosion.

Preparation and Performance of Micro-Arc Oxidation Ceramic Coating of Titanium Alloy in Low Current Density

2011 ◽  
Vol 335-336 ◽  
pp. 708-712
Author(s):  
Jian Jun Xi ◽  
Jun Zhao ◽  
Guo Jun Niu
Keyword(s):  
Titanium Alloy ◽  
Friction Coefficient ◽  
Surface Morphology ◽  
Current Density ◽  
Ceramic Coating ◽  
Low Power Consumption ◽  
Bipolar Pulse ◽  
Phosphate Silicate ◽  
Micro Arc Oxidation ◽  
And Performance

In this paper, Three types of electrolyte (phosphate, silicate, aluminum) are considered to make preparation for micro-arc oxidation coatings on titanium alloy by bipolar pulse MAO oxidation power with low power consumption (density of current less than 1A/dm2). Treated by micro-arc oxidation, dense micro-arc oxidation ceramic coating is formed on titanium alloy. Surface morphology and friction coefficient of MAO coating is analyzed. The research on the effect of NaF on ablation of MAO coating is prepared, which guides the configuration of the electrolyte later.

Corrosion and Wear Properties of h-BN Modified TC4 Titanium Alloy Micro-Arc Oxide Coatings

2022 ◽  
pp. 1-10
Author(s):  
X W Chen ◽  
P Ren ◽  
D F Zhang ◽  
J Hu ◽  
C Wu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Corrosion Resistance ◽  
Titanium Alloy ◽  
Hexagonal Boron Nitride ◽  
Corrosion Current ◽  
Ceramic Coatings ◽  
Element Distribution ◽  
Wear Properties ◽  
Tc4 Titanium Alloy ◽  
Micro Arc Oxidation

In this study, ceramic coatings were prepared on the surface of TC4 titanium alloy by micro-arc oxidation (MAO). The morphology, element distribution and phase composition of MAO coatings were analyzed by SEM, EDS, XRD and other analytical methods. The effect of hexagonal boron nitride(h-BN) doping on wear resistance and corrosion resistance of micro-arc oxidation layer was studied. The results show that the coating is mainly composed of rutile TiO2, anatase TiO2 and a small amount of h-BN. Furthermore, the composite coating containing h-BN was less porous than particle-free coating. The test results show that h-BN doping slightly affects the hardness of the MAO coating, and it is helpful in improving the thickness, corrosion resistance and wear resistance of the coatings. When the amount of h-BN is 3 g/L, the corrosion current density of the coating is the smallest; When the addition of h-BN is 1.5 g/L, the friction coefficient of the coating is the smallest. The wear mechanism was adhesive wear, accompanied by slight abrasive wear.

Design of Scanning Micro-Arc Oxidation Forming Ceramic Coatings on 2024 Aluminium Alloy

2011 ◽  
Vol 189-193 ◽  
pp. 1296-1300 ◽  
Author(s):  
Peng Xiang Lv ◽  
Guan Xin Chi ◽  
Dong Bo Wei ◽  
Shi Chun Di
Keyword(s):  
Arc Discharge ◽  
Ceramic Coatings ◽  
Element Distribution ◽  
Treatment Technique ◽  
X Ray Diffraction ◽  
High Stage ◽  
Micro Arc Oxidation ◽  
Anodic Voltage ◽  
Oxidation Technology ◽  
Plasma Electrolytic

Micro-arc oxidation (MAO), also called plasma electrolytic oxidation (PEO), anodic spark deposition (ASD), or micro-arc discharge oxidizing (MDO), is an effective surface treatment technique which come from anodic oxidation technology. Via increasing the anodic voltage breaking through faraday area to a high stage accompanied by micro-arc discharge phenomenon, It indicated the ceramic coatings thickness increase along with the scanning times increase, while the thickness increment reduces. The phase composition, morphology and element distribution was studied by X-ray diffraction, scanning electron microscopy and line scanning. The morphology of the ceramic coatings shows it divided into compact layer and loose layer. And it composes of α-Al2O3 and γ-Al2O3.

Effect of K2Cr2O7 on Anti-Biofouling Properties of MAO Coating on Titanium Alloy Surface

2014 ◽  
Vol 513-517 ◽  
pp. 173-176
Author(s):  
Qiang Yao ◽  
Si Rong Yu ◽  
Hong Chao Chu
Keyword(s):  
Titanium Alloy ◽  
Ceramic Coating ◽  
Average Diameter ◽  
Ceramic Coatings ◽  
Immersion Test ◽  
Alloy Surface ◽  
Concentration Increase ◽  
Composite Electrolyte ◽  
Aluminium Titanate ◽  
Micro Arc Oxidation

Ceramic coatings were prepared on Ti6Al4V alloy surface by applying micro-arc oxidation (MAO) technique. K2Cr2O7 was added into the aluminate-based composite electrolyte for preparing coatings containing Cr. The coatings' morphologies were observed using SEM and their composition was characterized using XRD and EDS. Research shows that the working voltage of MAO reaction was lower after adding K2Cr2O7. The SEM pictures show that the average diameter of micropores decreased while the number increased as the K2Cr2O7 concentration increase. The coatings contain rutile TiO2, anatase TiO2, aluminium titanate (Al2TiO5) and Cr0.222Ti0.778O1.889 (when adding 1.5g/L K2Cr2O7). The EDS results show that all coatings contained Cr after adding K2Cr2O7 into electrolyte. After immersion test for half year, results show that ceramic coating containing chromium has lower anti-biofouling properties than the substrate.

Variable Parameter Processes of Micro-Arc Oxidation for Aluminium Alloy

2011 ◽  
Vol 704-705 ◽  
pp. 1273-1278
Author(s):  
Cheng Gao ◽  
Jin Yong Xu ◽  
Xuan Yi Shi ◽  
Ya Juan Liu ◽  
Jing Chun Zhang ◽  
...  
Keyword(s):  
Growth Rate ◽  
Wear Rate ◽  
Ceramic Coating ◽  
Early Stage ◽  
Variable Parameter ◽  
Ceramic Coatings ◽  
Constant Current ◽  
Constant Voltage ◽  
Micro Arc Oxidation ◽  
The Way

In micro-arc oxidation process, ceramic coating had a rapid growth all along by the way of constant current oxidation, and ceramic coating had a low roughness by the way of constant voltage oxidation. But few research focus on the mixed control process of constant current oxidation and constant voltage oxidation. In this paper we propose a variable parameter process that can combine the advantages of constant current and constant voltage oxidation for the first time. The growth kinetics of different technics was analyzed according to the change law of current and voltage. Surface topographs of ceramic coating were observed using scanning electron microscopy (SEM). The friction tests were carried out using a self-made friction tester. The results show that ceramic coating has an upper growth rate and a low roughness by the process of constant current+constant voltage oxidation. The ceramic coating has a high growth rate by process of constant voltage+constant current oxidation. The results of friction test indicate that the wear rate and roughness of ceramic coating are positive correlation at early stage of friction. While the ceramic coatings treated by different technics have the close wear rate at stable friction stage, which embodies the inner layer of ceramic coating has a well antiwear behavior.

Preparation and performance of alumina ceramic coating doped with aluminum nitride by micro arc oxidation

2020 ◽  
Vol 46 (10) ◽  
pp. 17112-17116 ◽  
Author(s):  
Wei Yang ◽  
Shangkun Wu ◽  
Dapeng Xu ◽  
Wei Gao ◽  
Yuhong Yao ◽  
...  
Keyword(s):  
Aluminum Nitride ◽  
Ceramic Coating ◽  
Alumina Ceramic ◽  
Micro Arc Oxidation ◽  
And Performance

Anti-Wear Coating Grown by Micro-Plasma Oxidation on Aluminum Alloys in the Solution of Aluminate-Titania

2011 ◽  
Vol 239-242 ◽  
pp. 667-670 ◽  
Author(s):  
Li Gong Zhang ◽  
Gui Mei Zhao ◽  
Xiao Ming Lai
Keyword(s):  
Aluminum Alloys ◽  
Ceramic Coating ◽  
Ceramic Coatings ◽  
Wear Property ◽  
Plasma Oxidation ◽  
X Ray Diffraction ◽  
Electrolytic Solution ◽  
X Ray ◽  
Hardness Tester ◽  
Wear Coating

In this paper, Aluminum trioxide ceramic coatings were grown on surfaces of 2024 Aluminum alloys by micro-plasma oxidation in an aluminate electrolytic solution. In order to decrease the density of the pores and increase the anti-wear property of the ceramic coatings, Titania were added into the aluminate electrolytic solution. The struture and anti-wear property of the produced ceramic coatings were measured by X-ray diffraction, scanning electron microscope , hardness tester and frictionometer. The results show that the thickness of the ceramic coating is about 24±1 μm, surfaces of the ceramic coatings are very uniform. The hardness of the doped coating is up to 930 HV, and the wear property of the coating is the more excellent than that of undoped coating.

The Effects of Magnetic Field on Micro-Arc Oxidation Ceramic Coating on Magnesium Alloys

2014 ◽  
Vol 960-961 ◽  
pp. 143-147
Author(s):  
Jun Zhao ◽  
Jian Jun Xi ◽  
Zhi Gang Wang ◽  
Chun Ping Zhao
Keyword(s):  
Magnetic Field ◽  
Corrosion Resistance ◽  
Electron Microscope ◽  
Friction Coefficient ◽  
Ceramic Coating ◽  
Ceramic Coatings ◽  
Oxidation Method ◽  
Polarization Test ◽  
Micro Arc Oxidation ◽  
Scanning Electron

Ceramic coatings were prepared on ZM5 magnetism substrate by micro-arc oxidation method with and without magnetism filed in silicate electrolyte. The morphology of the MAO coatings was investigated by scanning electron microscope (SEM). The friction coefficient of the MAO coatings prepared with magnetism is about 0.2 and more stable than the coatings prepared without magnetism. The polarization test indicated that the coating prepared with magnetism has better corrosion resistance.

Corrosion Resistance of the Ceramic Coating Formed by Micro-Plasma Arc Oxidation on AZ91D Alloy

2007 ◽  
Vol 336-338 ◽  
pp. 2451-2453
Author(s):  
Shu Hua Li ◽  
Fu Chi Wang
Keyword(s):  
Magnesium Alloy ◽  
Ceramic Coating ◽  
Ceramic Coatings ◽  
Az91d Alloy ◽  
Plasma Arc ◽  
X Ray Diffraction ◽  
Compact Layer ◽  
Az91d Magnesium Alloy ◽  
Loose Layer ◽  
Salt Fog

The ceramic coating was formed by micro-plasma arc oxidation (MPAO) on AZ91D magnesium alloy. The surface and section morphology of coatings were observed using scanning electron microscopy. The phase composition of coatings was analyzed by X-ray diffraction. The method of salt fog experimental was carried out to proof-test performances of anti-corrosion of material. The results showed that the ceramic coating was composed by loose layer and compact layer. The coating surface has a large number of grains with various sizes. In addition, there is also a lot of pore in the loose layer, but the compact layer is tighter than the loose layer. Compact layer has a good combination with substrate magnesium alloy. The MPAO coating is mainly composed of silica oxide (MgAl2Si3O12 and β-Mg2SiO4 and (Mg4Al14) (Al4Si2)O20) and composite oxide of Mg and Al (δ-MgAl28O4). The performance of resistant corrosion of AZ91D coved by ceramic coating is higher than AZ91D magnesium alloy. The corrosion ratio of AZ91D alloy coved by ceramic coatings to AZ91D alloy is 1:8.61.

EFFECTS OF α-Al2O3 NANOADDITIVE ON THE PROPERTIES OF CERAMIC COATINGS PREPARED IN BORATE ELECTROLYTE BY MICRO-ARC OXIDATION

2012 ◽  
Vol 19 (04) ◽  
pp. 1250038 ◽  
Author(s):  
H. X. LI ◽  
H. H. ZHU ◽  
X. WU ◽  
Z. G. JI
Keyword(s):  
Phase Composition ◽  
Great Influence ◽  
Ceramic Coatings ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Micro Arc Oxidation ◽  
Edx Analyses ◽  
6063 Aluminum Alloy ◽  
Α Al2o3 ◽  
Wear Tests

Ceramic coatings have been synthesized on 6063 aluminum alloy by micro-arc oxidation (MAO) technique in the solution of Na2B4O7 electrolyte with and without α- Al2O3 nanoadditive. Effects of α- Al2O3 nanoadditive on the phase composition, micro-structure, micro-hardness, adhesion and wear resistance of the prepared ceramic coatings have been investigated in this paper. The phase composition and microstructure of the MAO coatings were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive spectroscopy (EDX) analyses, respectively. Micro-hardness, adhesion and tribological and wear tests were also performed. The results showed that the α- Al2O3 nanoadditive doped in the electrolyte had great influence on the structural and mechanical properties of the ceramic coatings.

Sign in / Sign up

Export Citation Format

Share Document