Electrochemical corrosion and anisotropic tribological properties of bioinspired hierarchical morphologies on Ti-6Al-4V fabricated by laser texturing

Abstract In this work, polyetheretherketone-based TiN/PEEK708 nanocomposite coatings on oxygen hardened Ti-6Al-4V titanium alloy substrates were fabricated by using cathodic electrophoretic deposition and post-heat treatment. The microstructure of coatings was investigated by using scanning electron microscopy, transmission electron microscopy, and X-ray diffractometry. The scratch resistance, tribological properties, and electrochemical corrosion resistance were also studied. The results show that homogeneous TiN/PEEK708 coatings may be deposited from ethanol-based suspensions containing cationic chitosan polyelectrolyte, which provides electrosteric stabilization of the suspension. Heat treatment densified the coatings and changed the PEEK structure from amorphous to semi-crystalline. The coatings were characterized by very good scratch resistance, with no cohesive and adhesive cracks being observed up to the load of 30 N. They reduced the coefficient of friction from 0.70 for the baseline alloy and 0.65 for the oxygen hardened alloy to 0.30. They also significantly increased the wear resistance of the alloy during dry sliding contact with an alumina ball. The wear rate of the coated oxygen hardened alloy was about 70 and 650 times lower in comparison with the oxygen hardened and baseline alloy, respectively. The corrosion studies demonstrated that the baseline and oxygen hardened alloy have comparable corrosion resistance. The TiN/PEEK708 coating enhanced the electrochemical corrosion resistance of the alloy in the NaCl aqueous solution.

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Laser Texturing as Substrate Preparation Technique for Improved Corrosion Performance on WC-Co HVOF Coatings on AZ91D

Asian Journal of Engineering and Applied Technology ◽

10.51983/ajeat-2018.7.2.950 ◽

2018 ◽

Vol 7 (2) ◽

pp. 80-86

Author(s):

Sachpreet Singh Aulakh ◽

Gagandeep Kausha ◽

Neeraj Bala

Keyword(s):

Chemical Properties ◽

Electrochemical Corrosion ◽

Surface Characteristics ◽

Vital Role ◽

Preparation Technique ◽

Corrosion Performance ◽

Substrate Preparation ◽

Laser Texturing ◽

Electrochemical Testing ◽

Good Surface

Substrate preparation plays a vital role in the performance of thermal spray coatings. Adherence of the coating to the substrate depends on surface characteristics like; mechanical interlocking, physio-chemical properties of surface and metallurgical bonding. The surface characteristics depend to great extent on the method used for substrate preparation. In the present study, WC-12Co and WC-17Co coatings were deposited on AZ91D samples prepared using laser texturing as substrate preparation technique. Laser textured substrate was characterized using scanning electron microscopy and surface roughness tester. Bond strength of the coating was determined using ASTM 633C pull off test. SEM was used to study the morphology of the coating; XRD/EDAX techniques were used to study the structure of the coatings. Porosity and micro-hardness of the coatings were also measured. Corrosion performance of the coatings was determined using Potentiodynamic and EIS electrochemical corrosion testing techniques. The coatings are found to have good surface and mechanical properties. Both WC-12Co and WC-17Co demonstrated good corrosion performance during electrochemical testing. However, WC-12Co was found to better protect the AZ91D compared to WC-17Co.

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Strengthening of Tribological Properties by Laser Texturing: Impact of Process Variables and Applications – Review and Future Trends

10.2174/9789815036305121010014 ◽

2021 ◽

pp. 175-197

Keyword(s):

Tribological Properties ◽

Future Trends ◽

Process Variables ◽

Laser Texturing

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Effect of Enhanced Ion Transfer in Process-Induced Electrochemical Corrosion on Surface Morphology and Tribological Properties

Journal of Microelectromechanical Systems ◽

10.1109/jmems.2016.2645903 ◽

2017 ◽

Vol 26 (2) ◽

pp. 424-432 ◽

Cited By ~ 1

Author(s):

Erik C. Anderson ◽

Alyssa L. Macuk ◽

Shannon J. Timpe

Keyword(s):

Surface Morphology ◽

Tribological Properties ◽

Electrochemical Corrosion ◽

Ion Transfer

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Influence of laser texturing on tribological properties of DLC coatings

Production Engineering Archives ◽

10.30657/pea.2021.27.15 ◽

2021 ◽

Vol 27 (2) ◽

pp. 119-123

Author(s):

Norbert Radek ◽

Dorota Tokar ◽

Artur Kalinowski ◽

Jacek Pietraszek

Keyword(s):

Tribological Properties ◽

Sliding Friction ◽

Surface Texturing ◽

Picosecond Laser ◽

Microstructure Analysis ◽

Surface Microstructure ◽

Radiation Wavelength ◽

Laser Texturing ◽

Dlc Coatings ◽

Surface Microgeometry

Abstract The work presents the use of laser texturing of DLC coatings to improve tribological properties. The coatings were applied by the PVD method to the rings made of 4H13 steel. The surface texturing was performed with the TruMICRO 5325c picosecond laser with the radiation wavelength λ = 343 nm. The surface microstructure analysis, surface microgeometry and microhardness measurements and tribological tests were carried out. The problem presented in the paper can be used to extend the knowledge of the areas of application of DLC coatings, especially in sliding friction pairs.

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Improving the Tribological Properties and Biocompatibility of Zr-Based Bulk Metallic Glass for Potential Biomedical Applications

Materials ◽

10.3390/ma13081960 ◽

2020 ◽

Vol 13 (8) ◽

pp. 1960

Author(s):

Victoria Sawyer ◽

Xiao Tao ◽

Huan Dong ◽

Behnam Dashtbozorg ◽

Xiaoying Li ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Tribological Properties ◽

Bulk Material ◽

Electrochemical Corrosion ◽

Optical Emission ◽

Transmission Electron ◽

Scanning Transmission ◽

The Coefficient Of Friction ◽

Hardened Case

Zr-based bulk metallic glasses (Zr-BMGs) are potentially the next generation of metallic biomaterials for orthopaedic fixation devices and joint implants owing to their attractive bulk material properties. However, their poor tribological properties and long-term biocompatibility present major concerns for orthopaedic applications. To this end, a novel surface modification technology, based on ceramic conversion treatment (CCT) in an oxidising medium between the glass transition temperature and the crystallisation temperature, has been developed to convert the surface of commercially available Zr44Ti11Cu10Ni11Be25 (Vitreloy 1b) BMG into ceramic layers. The engineered surfaces were fully characterised by in-situ X-ray diffraction, glow-discharge optical emission spectroscopy, scanning electron microscopy, transmission electron microscopy, and scanning transmission electron microscopy. The mechanical, chemical, and tribological properties were evaluated respectively by nano-indentation, electrochemical corrosion testing, tribological testing and the potential biocompatibility assessed by a cell proliferation assay. The results have demonstrated that after CCT at 350 °C for 40 h and at 380 °C for 4.5 h the original surfaces were converted into to a uniform 35–55-nm-thick oxide layer (with significantly reduced Ni and Cu concentration) followed by a 200–400-nm-thick oxygen-diffusion hardened case. The surface nano hardness was increased from 7.75 ± 0.36 to 18.32 ± 0.21 GPa, the coefficient of friction reduced from 0.5–0.6 to 0.1–0.2 and the wear resistance improved by more than 60 times. After 24 h of contact, SAOS-2 human osteoblast-like cells had increased surface coverage from 18% for the untreated surface to 46% and 54% for the 350 °C/40 h and 380 °C/4.5 h treated surfaces, respectively. The significantly improved tribological properties and biocompatibility have shown the potential of the ceramic conversion treated Zr-BMG for orthopaedic applications.

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Alumina Reinforcement of Inconel 625 Coatings by Cold Gas Spraying

Metals ◽

10.3390/met10091263 ◽

2020 ◽

Vol 10 (9) ◽

pp. 1263

Author(s):

Sergi Dosta ◽

Nuria Cinca ◽

Alessio Silvello ◽

Irene G. Cano

Keyword(s):

Tribological Properties ◽

Electrochemical Corrosion ◽

Corrosion Current ◽

Inconel 625 ◽

Homogeneous Distribution ◽

Nozzle Clogging ◽

Good Oxidation Resistance ◽

Mechanical And Tribological Properties ◽

Oxidation And Corrosion ◽

Cold Gas

Reinforced Inconel625 coatings have been successfully deposited by means of cold gas spray (CGS). Alumina has been simultaneously sprayed achieving a homogeneous distribution along the deposit with good cohesion between particles. The aim of this study was to investigate whether ceramic reinforcement could improve the mechanical and tribological properties of Inconel625 cold-sprayed coatings, while keeping the oxidation and corrosion resistance capacity. Furthermore, alumina particles were found to improve the spraying feasibility, by avoiding WC nozzle clogging during the process. A proper optimization of the spraying conditions was carried out in order to obtain the lowest possible porosity and best embedment of the alumina. Then, the mechanical and tribological properties as well as corrosion and oxidation behavior were characterized. Alumina acts as a reinforcement, improving the effects of abrasive and sliding wear. Regarding the oxidation and corrosion behavior, the coatings exhibit reasonably good oxidation resistance at temperatures up to 900 °C. The electrochemical corrosion performance in NaCl solution showed potentially lower noble corrosion values and corrosion current densities than bulk Inconel.

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