Siloxane-polyacrylic sol-gel coatings with alkyl and perfluoroalkyl chains: Synthesis, composition, thermal properties and long-term corrosion protection

2021 ◽  
pp. 151578
Author(s):  
Ingrid Milošev ◽  
Damir Hamulić ◽  
Peter Rodič ◽  
Charly Carrière ◽  
Sandrine Zanna ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Corrosion Protection ◽  
Sol Gel ◽  
Synthesis Composition

scholarly journals Corrosion Protection of 6061 Aluminum Alloys by Sol-Gel Coating Modified with ZnLaAl-LDHs

Coatings ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 478
Author(s):  
Youbin Wang ◽  
Qiuyu Huang ◽  
Bingtao Zhou ◽  
Zengyin Yuan ◽  
Yuezhou Wei ◽  
...  
Keyword(s):  
Aluminum Alloys ◽  
Corrosion Protection ◽  
Sol Gel ◽  
Precipitation Method ◽  
Corrosion Mechanism ◽  
Corrosion Performance ◽  
The Stability ◽  
Co Precipitation ◽  
Double Hydroxides

In this work, ZnLaAl layered double hydroxides (LDHs) were prepared by the co-precipitation method, and the ZnLaAl-LDHs nanosheets were embedded in sol-gel coating for the corrosion protection of 6061 aluminum alloys. The structure, morphology, and long-term anti-corrosion performance of sol-gel coating modified with ZnLaAl-LDHs were investigated. The structure and morphology analysis showed that nanosheets of ZnLaAl-LDHs are finer than those of ZnAl-LDHs, with the results suggesting that the La can refine the size of LDHs’ nanosheets and improve their nucleation rate. The results of long-term corrosion tests showed that the sol-gel coating with ZnLaAl-LDHs exhibits higher corrosion resistance and better stability compared with the sol-gel coating with ZnAl-LDHs, which indicates that the addition of La enhances the anti-corrosion performance of the LDHs and improves the stability of sol-gel coating with LDHs. Finally, the formation mechanism of ZnLaAl-LDHs and the corrosion mechanism of sol-gel coating with ZnLaAl-LDHs on 6061 aluminum alloys are both discussed in detail.

scholarly journals Photocatalytic Activity Enhancement of Low-pressure Cold-Sprayed TiO2 Coatings Induced by Long-term Water Vapor Exposure

2021 ◽  
Author(s):  
Seremak Wioletta ◽  
Baszczuk Agnieszka ◽  
Jasiorski Marek ◽  
Gibas Anna ◽  
Winnicki Marcin
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Activity ◽  
Water Vapor ◽  
Sol Gel ◽  
Low Pressure ◽  
Oxygen Depletion ◽  
Amorphous Structure ◽  
Industrial Applications ◽  
Additional Parameter

AbstractThis work shows that the titanium dioxide coatings obtained by low-pressure cold gas spraying with the use of the sol–gel amorphous TiO2 powder are characterized by photocatalytic activity despite their partial amorphous content. Moreover, the research outcome suggests that the decomposition rate of organic pollutants is enhanced after long-term exposure to moisture. The condensation humidity test is not detrimental to the continuity and integrity of the coating, but the phase composition of coatings changes—with the exposure to water vapor, the portion of the amorphous phase crystallizes into brookite. The mechanism responsible for the conversion of amorphous TiO2 into brookite is attributed to the water-driven dissolution and reprecipitation of TiO6 octahedra. It has been shown that an additional parameter necessary for the stabilization of the brookite is the oxygen depletion of the amorphous structure of titanium dioxide. Considering the results presented in this paper and the advantages of a portable, low-pressure cold spray system for industrial applications, it is expected that TiO2 coatings produced from a sol–gel feedstock powder can be further developed and tested as efficient photocatalysts.

scholarly journals 3C-SiC Nanowires In-Situ Modified Carbon/Carbon Composites and Their Effect on Mechanical and Thermal Properties

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 894 ◽  
Author(s):  
Hongjiao Lin ◽  
Hejun Li ◽  
Qingliang Shen ◽  
Xiaohong Shi ◽  
Tao Feng ◽  
...  
Keyword(s):  
Shear Strength ◽  
Thermal Properties ◽  
Sol Gel ◽  
Interlaminar Shear Strength ◽  
Mechanical And Thermal Properties ◽  
Initial Oxidation ◽  
Sic Nanowires ◽  
Out Of Plane ◽  
Interlaminar Shear

An in-situ, catalyst-free method for synthesizing 3C-SiC ceramic nanowires (SiCNWs) inside carbon–carbon (C/C) composites was successfully achieved. Obtained samples in different stages were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman scattering spectroscopy. Results demonstrated that the combination of sol-gel impregnation and carbothermal reduction was an efficient method for in-situ SiCNW synthesis, inside C/C composites. Thermal properties and mechanical behaviors—including out-of-plane and in-plane compressive strengths, as well as interlaminar shear strength (ILLS) of SiCNW modified C/C composites—were investigated. By introducing SiCNWs, the initial oxidation temperature of C/C was increased remarkably. Meanwhile, out-of-plane and in-plane compressive strengths, as well as interlaminar shear strength (ILLS) of C/C composites were increased by 249.3%, 109.2%, and 190.0%, respectively. This significant improvement resulted from simultaneous reinforcement between the fiber/matrix (F/M) and matrix/matrix (M/M) interfaces, based on analysis of the fracture mechanism.

Sign in / Sign up

Export Citation Format

Share Document