Corrosion behavior of Al2024‐T3, Al5052‐H32, and Al6061‐T6 aluminum alloys coated with DLC films in aviation fuel medium, Jet A‐1 and AVGAS 100LL

Abstract

In aircraft and storage fuel tanks, many environmental corrosion factors can be present, which can cause breakdown to the passive film of aluminum causing severe localized corrosion. Aiming to a solution to this problem, diamond-like carbon (DLC) films were deposited on substrates Al 2024-T3, Al 5052-H32, and Al 6061-T6. The substrates with and without DLC films were submitted to a corrosive immersion test with aviation fuel Jet-A1 and AVGAS 100LL. The surface morphology from aluminum substrates with and without DLC films was analyzed before and after 7 and 30 days of corrosive immersion tests by SEM. The adhesion of the DLC films was evaluated according to the ASTM-C1624 scratching test standard, and the optical profilometry was used to measure the thickness and roughness. Silver nanoparticles were also added in DLC films samples due to its antibacterial properties to check the stability and resistance against corrosive fuel medium. The results indicated an improvement of corrosion resistance just with DLC films. The silver nanoparticles did not present any advantages in this corrosion protection, and the aluminum alloys suffered more corrosion than when protected by DLC films. K E Y W O R D SAl 2024-T3, Al 5052-H32, Al 6061-T6.

Tribocorrosion Susceptibility and Cell Viability Study of 316L Stainless Steel and Ti₆Al₄V Titanium Alloy With and Without DLC Coatings

“…The thickness values were similar, since the deposition parameters employed were the same, with deposition during 120 min at Vb of -700 V. The thicknesses of the DLC coatings deposited on SS316L and Ti6Al4V were 1.59 and 1.33 μm, respectively. The deposition rates were approximately 2-fold higher than those obtained using DLC in a previous study by the same research group [11]. The growth rates observed here were 0.013 and 0.011 μm/min for the SS316L and Ti6Al4V substrates, respectively.…”

“…The configuration of deposition parameters such as voltage, current, power supply, work cycle, working pressure, and precursor type should provide a plasma environment with high ion density and the pulsed power supply favored a low free path between ions and the substrate surface, avoiding strong collisions [11]. The aim is to achieve an optimal collection of charged particles with ideal electrical conductivity, which collectively responds to the electromagnetic forces and chemical reactions during deposition.…”

“…Inside the plasma reactor, the gas precursors undergoing ionization may take the form of bundles of neutral ions, while also acting as highly charged gas clouds that may contain particulate material in the form of dust. During the deposition process, these particles can be deposited onto the surface of the coating, causing the formation of porous dimples or pinholes [11][12] that act as sites for the permeation of corrosive liquids or vapors through the coatings onto the substrate. The pores generated by dust from the deposition process are starting points for corrosion that reduces the lifetime of the coating.…”

Enhancing UV Radiation Resilience of DLC-Coated Stainless Steel with TiO2: A Dual-Layer Approach

“…This interlayer improves adhesion by forming a strong bond between the metal and carbon layers, thereby enhancing the overall durability and performance of the coating system. This approach ensures that the DLC coating remains securely attached to the metal substrate, even under challenging conditions [26,27]. Acetylene gas (C 2 H 2 ) was employed as the carbon precursor for the DLC layer.…”

Tribocorrosion Susceptibility and Cell Viability Study of 316L Stainless Steel and Ti6Al4V Titanium Alloy with and without DLC Coatings

“…Table 1 shows the chemical compositions of the 316L steel and the titanium alloy, including metallic, nonmetallic, and semi-metallic (such as silicon) elements. It can be seen that SS316L contains 22% chromium, which, during the deterioration of implants, may be delivered to the body in the form of ions including Cr6+, which can cause the development of cancer [3]. Other chemical elements present in lower concentrations include nickel, carbon, silicon, manganese, cobalt, and molybdenum.…”