Adhesively bonded CFRP/Al joints: Influence of the surface pretreatment on corrosion during salt spray test

The selection of appropriate surface pretreatments is one of the pending issues for the industrial application of cerium-based chemical conversion coatings (CeCC) as an alternative for toxic chromate conversion coating (CrCC). A two-step surface pretreatment based on commercial products has been successfully used here to obtain CeCC on AA2024-T3 and AA7075-T6. Specimens processed for 1 to 15 min in solutions containing CeCl3 and H2O2 have been studied by scanning electron microscopy coupled with energy-dispersive X-ray analysis (SEM-EDX), glow discharge optical emission spectroscopy (GDOES), potentiodynamic linear polarization (LP), electrochemical impedance spectroscopy (EIS), and neutral salt spray (NSS) tests. SEM-EDX showed that CeCC was firstly observed as deposits, followed by a general coverage of the surface with the formation of cracks where the coating was getting thicker. GDOES confirmed an increase of the CeCC thickness as the deposition proceed, the formation of CeCC over 7075 being faster than over 2024. There was a Ce-rich layer in both alloys and an aluminum oxide/hydroxide layer on 7075 between the upper Ce-rich layer and the aluminum matrix. According to LP and EIS, CeCC in all samples offered cathodic protection and comparable degradation in chloride-containing media. Finally, the NSS test corroborated the anti-corrosion properties of the CeCC obtained after the commercial pretreatments employed.

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Research on Shear Bearing Capacity of Reinforced Concrete Short Beam in Salt-Fog Environment

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.455-456.1079 ◽

2012 ◽

Vol 455-456 ◽

pp. 1079-1083

Author(s):

Wei Jun Yang ◽

Hong Jia Huang ◽

Wen Yu Jiang ◽

Yi Bin Peng

Keyword(s):

Reinforced Concrete ◽

Bearing Capacity ◽

Salt Spray ◽

Test Chamber ◽

Shear Capacity ◽

Salt Spray Test ◽

Concrete Members ◽

Short Beam ◽

Shear Bearing Capacity ◽

Salt Fog

Shantou atmospheric salt-fog environment is simulated with the comprehensive salt spray test chamber. By using reinforced concrete short beams under different water-cement radio, different corrosion time, the inclined section degradation rules of the corrosive reinforced concrete members are researched for establishing shear capacity of short beam formulas in salt-fog environment.

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ANTICORROSION PERFORMANCE OF SELF-HEALING POLYMERIC COATINGS ON LOW CARBON STEEL SUBSTRATES

Jurnal Teknologi ◽

10.11113/jt.v79.12268 ◽

2017 ◽

Vol 79 (7-4) ◽

Cited By ~ 1

Author(s):

Muhammad Ashraff Ahmad Seri ◽

Esah Hamzah ◽

Abdelsalam Ahdash ◽

Mohd Fauzi Mamat

Keyword(s):

Steel Substrate ◽

Salt Spray ◽

Immersion Test ◽

Salt Spray Test ◽

Test Method ◽

The Self ◽

Self Healing ◽

Pure Epoxy ◽

Steel Substrates ◽

Epoxy Paint

Recently, self-healing coating is classified as one of the smart coatings which has the ability to heal or repair damage of the coating to prevent further corrosion. The aim of this study is to synthesize the self-healing coatings from polymeric material and evaluate the performance and their corrosion behavior when coated on steel substrates. The corrosion tests were performed using immersion test and salt spray test method at room temperature. The immersion test shows that self-healing coating gives lower corrosion rate compared to pure epoxy paint, with a value of 0.02 and 0.05 mm/year respectively. Also, salt spray test shows similar trend as the immersion test, which is 0.11 and 0.19 mm/year for self-healing coating and pure epoxy paint respectively. While uncoated samples without any protection corroded at 0.89 mm/year. It was also found that the damage on self-healing coating was covered with zeolite from the microcapsules indicating that the self-healing agent was successfully synthesized and could function well. In other words, self-healing coating shows better corrosion resistance compared to the pure epoxy coating on steel substrate.

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The study of the effectiveness of corrosion protection of zinc-rich coating on the base of water sodium silicate

Practice of Anticorrosive Protection ◽

10.31615/j.corros.prot.2020.98.4-4 ◽

2020 ◽

Vol 25 (4) ◽

Keyword(s):

Corrosion Protection ◽

Sodium Silicate ◽

Electrochemical Impedance ◽

Paint Film ◽

Salt Spray ◽

Salt Spray Test ◽

Test Method ◽

Liquid Sodium ◽

Research Station ◽

Marine Research

The study is examines the assessment of the corrosion-protective properties of zinc-rich coating based on water sodium silicate (ZRC) using the Electrochemical Impedance Spectra (EIS) with AutoLAB PGSTAT204N. The system consists of three electrodes: Ag/AgCl reference electrode in 3 M solution of KCl, auxiliary electrode – Pt (8x8 mm) and working electrodes for determination potential (Ecorr) and impedance measurement, salt spray test method and natural teszzt method at Dam Bay Marine Research Station, Nha Trang, Khanh Hoa, Viet Nam. ZSC can provide good cathodic protection when zinc content is 70% by weight or more. ZSC with a mixing ratio of High Modulus Liquid Sodium Glass / Zinc Powde : 25/75 by weight (working title – TTL-VN) has good corrosion protection after 16 cycles salt spray test and after 18 months natural test in seawater. The paint film has basic parameters as adhesion – 4,41 MPa, flexural strength – 2 mm, pendulum hardness – 0,62 conventional units and initial coating potentia l – 0,96 V Ag/AgCl.

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Investigation on dual corrosion performance of magnesium-rich primer for aluminum alloys under salt spray test (ASTM B117) and natural exposure

Corrosion Science ◽

10.1016/j.corsci.2009.11.032 ◽

2010 ◽

Vol 52 (4) ◽

pp. 1453-1463 ◽

Cited By ~ 31

Author(s):

Shashi S. Pathak ◽

Michael D. Blanton ◽

Sharathkumar K. Mendon ◽

James W. Rawlins

Keyword(s):

Aluminum Alloys ◽

Salt Spray ◽

Salt Spray Test ◽

Corrosion Performance ◽

Natural Exposure

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Corrosion behavior of Al film on uranium in salt spray test

RSC Advances ◽

10.1039/c6ra28407h ◽

2017 ◽

Vol 7 (25) ◽

pp. 14981-14988

Author(s):

Yanping Wu ◽

Shengfa Zhu ◽

Peng Shi ◽

Biaojie Yan ◽

Dingzhou Cai ◽

...

Keyword(s):

Corrosion Behavior ◽

Salt Spray ◽

Salt Spray Test ◽

Neutral Salt

The corrosion behavior of Al film coated uranium and bare uranium under neutral salt spray conditions are evaluated.

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Surface and Fracture Surface Analysis of Thermally Bonded Metal/FRP Joints

Materials Science Forum ◽

10.4028/www.scientific.net/msf.825-826.328 ◽

2015 ◽

Vol 825-826 ◽

pp. 328-335 ◽

Cited By ~ 2

Author(s):

Daisy Nestler ◽

Claudia Döhler ◽

Bernhard Wielage ◽

Guntram Wagner

Keyword(s):

Fracture Surface ◽

Surface Morphology ◽

Joint Strength ◽

Chemical Bonds ◽

Chemical Condition ◽

Adhesively Bonded ◽

Surface Pretreatment ◽

Reinforced Plastics ◽

Fracture Surface Analysis ◽

Fractured Surface

The increasing implementation of fibre-reinforced plastics (FRP) leads to a broad utilization of metal/FRP joints. The examination of adhesively bonded metal/FRP joints is focusing on the maximum joint strength and the surface pretreatment used to promote it. A deeper understanding of the mechanisms behind the correlation is lacking. Along with the chemical condition of the surface (free chemical bonds, polarity, etc.) the surface morphology plays an important role. This study addresses the connection between the surface morphology and joint strength. The investigation of the surface morphology of the metallic joining area and the fractured surface of both joining partners by means of imaging and tactile methods and the results are presented.

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