Construction of lubricant composite coating on Ti6Al4V alloy using micro-arc oxidation and grafting hydrophilic polymer

In this study, the phase transition of secondary phase particles in a composite coating is used to estimate the temperature field of the molten pool on a Ti6Al4V alloy in the micro-arc oxidation (MAO) process. The behavior of the sparks and the molten pool during the MAO process was observed in real-time by a long-distance microscope. The microstructures and compositions of the composite coatings were studied by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The results revealed that, for the temperature field distribution range of the molten pool in the active period, the lower limit is 2123 K and the upper limit is not lower than 3683 K. The reason for the multiphase coexistence is that the high-temperature phase is retained by the rapid cooling effect of the electrolyte, and the low-temperature phase is formed due to secondary phase transformation during the long active time of the molten pool temperature field. The strengthening mechanism of the composite coating prepared by adding the secondary phase particles is elemental doping rather than particle enhancement. The secondary phase particles are able to enter the composite coating by adhering to the surface during the cooling process. The secondary phase particles will then be wrapped into the coating in the next active period.

Download Full-text

Formation mechanism and adhesive strength of a hydroxyapatite/TiO2 composite coating on a titanium surface prepared by micro-arc oxidation

Applied Surface Science ◽

10.1016/j.apsusc.2015.11.086 ◽

2016 ◽

Vol 362 ◽

pp. 109-114 ◽

Cited By ~ 53

Author(s):

Shimin Liu ◽

Baoe Li ◽

Chunyong Liang ◽

Hongshui Wang ◽

Zhixia Qiao

Keyword(s):

Composite Coating ◽

Formation Mechanism ◽

Adhesive Strength ◽

Titanium Surface ◽

Micro Arc Oxidation

Download Full-text

Biological and antibacterial properties of the micro-nanostructured hydroxyapatite/chitosan coating on titanium

Scientific Reports ◽

10.1038/s41598-019-49941-0 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 10

Author(s):

Baoe Li ◽

Xiaomei Xia ◽

Miaoqi Guo ◽

Yu Jiang ◽

Yu Li ◽

...

Keyword(s):

Composite Coating ◽

Antibacterial Property ◽

Antibacterial Properties ◽

Dip Coating ◽

Ha Coating ◽

Coating Method ◽

Micro Arc Oxidation ◽

Promising Application ◽

Sbf Solution ◽

Dip Coating Method

Abstract Titanium (Ti) is the widely used implant material in clinic, however, failures still frequently occur due to its bioinertness and poor antibacterial property. To improve the biological and antibacterial properties of Ti implants, micro-nanostructured hydroxyapatite (HA) coating was prepared on Ti surface by micro-arc oxidation (MAO), and then the antibacterial agent of chitosan (CS) was loaded on the HA surface through dip-coating method. The results showed that the obtained HA/CS composite coating accelerated the formation of apatite layer in SBF solution, enhanced cell adhesion, spreading and proliferation, and it also inhibited the bacterial growth, showing improved biological and antibacterial properties. Although, with the increased CS amount, the coverage of HA coating would be enlarged, resulting in depressed biological property, however, the antibacterial property of the composite coating was enhanced, and the cytotoxicity about CS was not detected in this work. In conclusion, the HA/CS coating has promising application in orthopedics, dentistry and other biomedical devices.

Download Full-text

Fabrication and Characterization of Porous Micro-arc Oxidation/Al Composite Coating: Bio-inspired Strategy from Cancellous Bone Structure

Journal of Materials Engineering and Performance ◽

10.1007/s11665-019-04533-x ◽

2019 ◽

Vol 29 (1) ◽

pp. 87-97 ◽

Cited By ~ 1

Author(s):

Shi-lin Ming ◽

Dong Qin ◽

Zheng-yang Li ◽

Yuan Ding ◽

Ming Liang ◽

...

Keyword(s):

Composite Coating ◽

Cancellous Bone ◽

Bone Structure ◽

Al Composite ◽

Micro Arc Oxidation ◽

Fabrication And Characterization ◽

Cancellous Bone Structure

Download Full-text

Study on Thermal-Shock-Resistance of the Composite Coating of 20 Steel Substrate by Hot Dip Aluminum and Micro-Arc Oxidation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.723.450 ◽

2016 ◽

Vol 723 ◽

pp. 450-453

Author(s):

Xiao Feng Sun ◽

Yuan Lin Huang ◽

Wei Song ◽

Ming Ming Sun

Keyword(s):

Residual Stress ◽

Thermal Shock ◽

Composite Coating ◽

Thermal Shock Resistance ◽

Steel Substrate ◽

Steel Plates ◽

Micro Hardness ◽

Combined Process ◽

Micro Arc Oxidation ◽

Shock Resistance

By combined process of hot dip aluminum and micro–arc oxidation, a multilayer composite coating was obtained on the surface of 20 steel plates. The micro-hardness, morphology, residual stress and thermal-shocking performance of the coating were investigated by HVS-1000 micro-hardness instrument, SEM, X-350 stress instrument and etc. The results showed that the micro-hardness of the coating appeared hard-soft-hard from surface to inner, the effective thermal-shock times of the coating was 130, its residual stress of the coating was 181.7 MPa after hot shock 80 times.

Download Full-text

Corrosion and Oxidation Protection of Ti6Al4V Alloy by an Inorganic Metal Modified Silicate Composite Coating

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.1952 ◽

2010 ◽

Vol 654-656 ◽

pp. 1952-1955 ◽

Cited By ~ 1

Author(s):

Cheng Wang ◽

Sheng Long Zhu ◽

Fu Hui Wang

Keyword(s):

Thermal Shock ◽

Composite Coating ◽

Salt Spray ◽

Mass Gain ◽

Isothermal Oxidation ◽

Ti6al4v Alloy ◽

Coated Alloy ◽

Oxidation Properties ◽

Oxidation And Corrosion ◽

Corrosion And Oxidation

An inorganic metal modified silicate composite coating was developed to protect the corrosion and oxidation of Ti6Al4V alloy at 650°C. The properties of the coatings were investigated by oxidation and corrosion experiments, and the microstructure of the coatings was studied by SEM. The isothermal oxidation results indicated that the Ti6Al4V alloy suffered serious oxidation after exposed for 100h at 650°C and the mass of the alloy gained almost lineally, while the coated alloy had almost no mass gain and the coatings keep intact after oxidation. The salt spray test for 20h and oxidation at 650°C for 2h was carried out to investigate the corrosion and oxidation properties of the coatings. The results indicated that the alloy experienced serious corrosion after experiment for 20 cycles, while the coated alloy did not corrode after the experiments. The thermal shock experiments indicated that the coatings could withstand 50 times thermal shock when kept for 5min at 700°C and then immediately put into 3.5%NaCl solution at room temperature.

Download Full-text