Improvement of corrosion resistance of AA2024-T3 using femtosecond laser peening without protective and confining medium

Abstract

This work reports for the first time the effect of femtosecond laser shock peening (fLSP) without a sacrificial overlay under atmospheric conditions (no confinement) on the corrosion behaviour of AA2024-T3. After fLSP and additional exposure to air a superhydrophobic state (   ± 4°) is achieved. Moreover, fLSPed corrosion-resistant surface contributes to increased polarization resistance, reduced corrosion current and lower anodic dissolution, with long-term stability in aggressive chloride solution. Furthermore, SEM/EDS /2/ characterisation reveals reduction in pitting and complete eradication of intergranular corrosion (IGC) attack due to reduced metal/electrolyte contact area and homogeneous, refined microstructure which prevents chain-link IGC propagation.

Preparation of transparent nanocomposites from UV‐ and thermo‐curable epoxyacrylate and graphene oxide for the application of corrosion protection coatings

“…From the EIS measurement, generally, the larger the axial radius of the impedance arc shown in the Nyquist pattern is, the better are the corrosion protection properties for coatings. In addition, the impedance value at the lowest frequency ( f = 0.01 Hz) of the Bode plots has also been commonly used as a good indicator of a coating's shielding performance . The Nyquist and Bode plots of the EA/GO‐coated steel plates are presented in Fig.…”

Energy Density Effect of Laser Alloyed TiB2/TiC/Al Composite Coatings on LMZ/HAZ, Mechanical and Corrosion Properties

“…Increased resistance to anodic dissolution and reduced pitting propagation rate can be attributed to more chemical stable surface state and to the development of surface CRS [43,65]. Figure 11 shows typical SEM/BEI micrographs of the surface condition after polarization tests of LSA TiC/TiB2/Al composite coating sample (Figure 11a) and the untreated/substrate Al alloy sample Afterwards, to obtain additional insight of general resistance against anodic dissolution in a Clē nvironment, the ∆E/∆i gradient, proposed by Trdan et al [63,64], was considered. Analysis confirmed a distinctive shift in ∆E/∆i gradient with the LSA samples, with more than 211% higher value compared to the untreated one.…”

“…Results of ΔE trends in Figure 10 confirm that both laser-alloyed samples provide lower dissolution in the anodic scan and better and faster ability for repassivation in the cathodic scan afterwards the corrosion has occurred. Afterwards, to obtain additional insight of general resistance against anodic dissolution in a Cl¯ environment, the ΔE/Δi gradient, proposed by Trdan et al [63,64], was considered. Analysis confirmed a distinctive shift in ΔE/Δi gradient with the LSA samples, with more than 211% higher value compared to the untreated one.…”

Enhancing the Corrosion Protection of AA2024-T3 Alloy by Surface Treatments Based on Piperazine-Modified Hybrid Sol–Gel Films

“…The AA2024-T3 aluminum alloy is widely used in aerospace, automotive and transportation industries generally due to their high strength-to-weight ratio, age-hardening, increased damage tolerance and durability, excellent fracture toughness and fatigue crack propagation and low manufacturing costs [1,2]. However, AA2024-T3 presents high contents of copper making it more susceptible to corrosion related to the distribution and composition of intermetallic particles [2,3]. These particles are considered the initiation sites for localized corrosion acting either as anodic or cathodic regions [4,5].…”