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A.M. Kooijman

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Authored

6 records found

Molybdate as corrosion inhibitor for hot dip galvanised steel scribed to the substrate

A study based on global and localised electrochemical approaches

Journal article - L. B. Coelho, E. B. Fava, A.M. Kooijman, Y. Gonzalez Garcia, M. G. Olivier, M. G. Olivier

The effect of sodium molybdate in inhibiting galvanic corrosion of Zn coating and mild steel is addressed. The inhibitor's performance was appraised by Zero Resistance Ammeter on HDG/mild steel galvanic coupling model in 0.05 M NaCl (+5 mM Na2MoO4) media. The effectiveness of Na2 ...

Multifunctional ZrB2-rich Zr1-xCrxBy thin films with enhanced mechanical, oxidation, and corrosion properties

Journal article - Babak Bakhit, Samira Dorri, Grzegorz Greczynski, A.M. Kooijman, Zhengtao Wu, Jun Lu, Johanna Rosen, J.M.C. Mol, Lars Hultman, Ivan Petrov, Ivan Petrov, Ivan Petrov, J. E. Greene, J. E. Greene, J. E. Greene

Refractory transition-metal (TM) diborides have high melting points, excellent hardness, and good chemical stability. However, these properties are not sufficient for applications involving extreme environments that require high mechanical strength as well as oxidation and corros ...

Local changes in the microstructure, mechanical and electrochemical properties of friction stir welded joints from aluminium of varying grain size

Journal article - Marta Orłowska, Florian Pixner, Andreas Hütter, A.M. Kooijman, Cezary Jasiński, Y. Gonzalez Garcia, Norbert Enzinger, Małgorzata Lewandowska

The present study shows results of friction stir welded (FSW) samples after different plastic deformation routes. The welds were made of coarse-grained and ultrafine-grained commercially pure aluminium. As a plastic deformation method a new hybrid process has been chosen, which r ...

LDH conversion films for active protection of AZ31 Mg alloy

Journal article - B. Pillado, B. Mingo, R. del Olmo, R. del Olmo, E Matykina, A.M. Kooijman, Y. Gonzalez Garcia, R. Arrabal, M. Mohedano

Zinc aluminium (Zn-Al) and lithium aluminium (Li-Al) – layered double hydroxides (LDH) coatings with incorporated inhibitors (Li−, Mo− and W−based) were successfully synthesized on AZ31 Mg alloy. Zn−Al LDH W and Li−Al LDH Li showed the highest corrosion resistance and were select ...

Vacuum Deposited Perovskites with a Controllable Crystal Orientation

Journal article - J. Yan, L.S. Stickel, L.S. Stickel, L. Mazzarella, O. Isabella, T.J. Savenije, L. van den Hengel, H. Wang, P. Ravi Anusuyadevi, A.M. Kooijman, X. Liu, B. Ibrahim, J.M.C. Mol, P. Taheri

The preferential orientation of the perovskite (PVK) is typically accomplished by manipulation of the mixed cation/halide composition of the solution used for wet processing. However, for PVKs grown by thermal evaporation, this has been rarely addressed. It is unclear how variati ...

Laying the experimental foundation for corrosion inhibitor discovery through machine learning

Journal article - C. Özkan, Lisa Sahlmann, Christian Feiler, M Zheludkevich, Sviatlana Lamaka, Parth Sewlikar, A.M. Kooijman, P. Taheri, J.M.C. Mol

Creating durable, eco-friendly coatings for long-term corrosion protection requires innovative strategies to streamline design and development processes, conserve resources, and decrease maintenance costs. In this pursuit, machine learning emerges as a promising catalyst, despite ...

Contributed

1 records found

Performance and mechanistic understanding of sodium galactarate as a green corrosion inhibitor and adhesion promoter for aluminium alloys

Master thesis - T. Potang, J.M.C. Mol, A.M. Kooijman, P. Taheri

Pretreatment has become a necessary process to enhance the surface chemistry and morphology of aluminium alloys before implementing subsequent corrosion protection measures, especially organic coating application. Traditionally, hexavalent-chromium-based pretreatment processes were frequently used in many industries, but hexavalent-chromium-based chemistries are now recognized as a potentially carcinogenic hazard and environmentally harmful. The development of alternative, non-toxic and eco-friendly corrosion inhibitor and pretreatment technologies has become of pivotal importance to industries as a basic license to operate and to reach a sustainable society as a whole. In this work, sodium galactarate (NaGal) was investigated as a potential green corrosion inhibiting chemical for hexavalent-chromium-free pretreatment and to serve as a coating adhesion promoter on aluminium alloy AW3003. The pretreatment layer formation was examined at five different pHs; 3, 4, 7, 10, and 11. The surface analysis was performed by Fourier transform infrared – reflection absorption spectroscopy (FTIR-RAS), contact angle measurement and white light interferometry (WLI). Samples with pretreatment layers formed in acidic and alkaline environment showed an increase in polar energy and surface roughness, which are strongly related to the coating adhesion properties, in line with the failure stresses obtained from the pull-off adhesion tests. The corrosion resistance was evaluated through the electrochemical behavior that was measured by linear polarization resistance (LPR), potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS) and open circuit potential (OCP) measurements. Immersion testing was performed to evaluate the pitting corrosion behavior. The pretreated sample exhibited less pitting than the reference sample, especially in an alkaline environment where aluminium alloys severely corrode due to limited protectiveness of the oxide layer. The pretreatment prevented the corrosion products from accumulating on the sample surface, limiting stain and smut layer redeposition, subsequently reducing the pitting corrosion.