Protective Layer Research Articles

Evaluation of N80 Carbon Steel Corrosion in 15 wt.% HCl Using Isatin-hydrazones: A Comprehensive Approach with Chemical, Electrochemical Techniques, and DFTB Calculations

The adverse effects of corrosion on industrial metals, particularly N80 carbon steel under acidic conditions, call for developing effective corrosion inhibitors. Due to their structural and electrical properties, isatine-hydrazones have emerged as possible corrosion inhibitors. This study investigates the corrosion inhibition capabilities of two specific Isatin-hydrazones, (E)-1-octyl-3-(2-(5-oxo-4,4-diphenyl)-4,5-dihydro-1H-imidazol-2-yl)hydrazono)indolin-2-one (OPHIHI) and (E)-3-(2-(5-oxo-4,4-diphenyl)-4,5-dihydro-1H-imidazol-2-yl)hydrazono)indolin-2-one (OIHIHI), on N80 carbon steel in a highly acidic medium. The study assessed the corrosion inhibition efficacy of OIHIHI and OPHIHI using both computational and experimental approaches. Weight loss measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy were used in the experiments. In contrast, density functional theory (DFT), molecular dynamics (MD), and tight-binding density functional theory (DFTB) were used in the computational analyses to elucidate the interaction mechanisms between the inhibitors and metal surfaces. The experiment demonstrated that both OPHIHI and OIHIHI effectively reduce corrosion rates in a 15 wt.% HCl solution at 303 K, achieving an inhibition efficiency of 96 % and 92 %, respectively, at an optimal 5 × 10−3 mol/L concentration. These inhibitors were discovered to form protective layers on the N80 carbon steel surface, offering mixed protective qualities (cathodic and anodic protection) with a preponderance of cathodic protection against carbon steel corrosion in 15 wt.% HCl. Computational studies supported the experiment's findings by demonstrating that isatin-hydrazones' superior electronic properties enabled them to form robust covalent bonds with the Fe (110) surface. Based on these results, OPHIHI and OIHIHI could be used as corrosion inhibitors in the oil and gas industry, particularly under highly acidic conditions.

Long cycle life aqueous zinc-ion battery enabled by a ZIF-N protective layer with electron-withdrawing group and zincophilicity on the Zn anode

Aqueous zinc-ion batteries (AZIBs) have garnered attention from researchers for their high theoretical capacity, safety, and low cost. However, the uncontrolled growth of zinc (Zn) dendrites and spontaneous corrosion reactions on the Zn anode significantly compromise the cycle life of AZIBs. This paper proposes the utilization of a novel zeolitic imidazole framework (ZIF-N) material with zincophilicity and hydrophilicity for modifying the Zn anode of AZIBs. ZIF-N incorporates numerous electron-withdrawing nitro groups at the Zn/ZIF-N interface to regulate the uneven electron distribution on the Zn anode. The modified Zn anode (Zn@ZIF-N) exhibits a lower polarization ratio (32.18 mV at 4 mA cm−2) and an extended cycle life (over 700 h at 4 mA cm−2). At a current density of 1 mA cm−2, the battery composed of a Zn@ZIF-N anode and NVO (NaV3O8) achieves a cycle life of 1600 cycles. This work provides a straightforward and cost-effective strategy for modifying the Zn anode to prolong the cycle life of AZIBs.

A comprehensive study on dry sliding wear and in-vitro degradation of AZ31 composite with 6 wt% Sn and 1.5 wt% TiO2 fabricated by stir casting

Abstract This experimental study investigates the dry sliding wear behaviour of novel AZ31 composite with 6 wt% Sn and 1.5 wt% TiO2 samples, focusing on the influence of sliding distance and normal load. Additionally, the research examines degradation rates during a 120-hour immersion period in simulated body fluid (SBF). The wear volume loss increased significantly with higher loads and longer sliding distances, showing a 142% rise from 1000 m to 2000 m and 76% from 2000 m to 3000 m under a 5 N load, peaking at a 25 N load over 5000 m. The specific wear rate dropped by 39% from 5 N to 15 N but increased with distance due to thermal softening, while the coefficient of friction decreased from 0.284 at 1000 m to 0.213 at 5000 m under 5 N. FESEM analysis revealed a transition from abrasive to delamination wear, with a protective oxide layer forming during sliding. Sn in the composite formed hard Mg2Sn intermetallic compounds, affecting crack formation and propagation under higher loads. Wear debris analysis showed both abrasive and delamination wear mechanisms, highlighting the protective role of the oxide layer. The degradation rate increased rapidly during the initial immersion stage in simulated body fluid (SBF), reaching 15.9 mm year−1 after 24 h, and then stabilizing after 48 h. Hydrogen evolution rose sharply from 0.28 ml cm−12 at 2 h to 7.6 ml cm−12 within 24 h, with a 92% increase by 48 h and an additional 38% increase from 48 to 72 h. Post-immersion FESEM analysis showed corroded surfaces with protective layers, cracks, and pitting corrosion. Magnesium hydroxide (Mg(OH)2) and hydroxyapatite played crucial roles in inhibiting corrosion. This analysis provides insights into the wear, and degradation dynamics of the AZ31-6Sn/1.5TiO2 composite, with implications for engineering applications and the development of biodegradable implants in biomedical fields.

An Utrastable Mg/Zr Modified P2‐Type Na2/3Ni1/3Mn2/3O2 Cathode Material for High‐Power Sodium‐Ion Batteries

AbstractP2‐Na2/3Ni1/3Mn2/3O2 demonstrates high energy density owing to its high specific capacity and high discharge voltage, but suffering from rapid performance decay due to severe structural degradation and aggravated surface side reaction during high‐voltage cycling. Herein, a Mg/Zr modified Na0.67Ni0.25Mg0.08Mn0.64Zr0.03O2 cathode is proposed with good structural stability and excellent cycling performance, showing reversible capacity of 123.2 mAh g−1 (0.1 C) and capacity retention of 99.1% after 100 cycles. The cycling stability is outstanding among P2‐type cathodes reported so far. In situ XRD analyses reveal a suppressed P2‐O2 phase transition after Mg modification, further incorporation of Zr greatly stabilizes the layered structure as some Zr ions reside in the Na layer providing a pinning effect to reduce the slide of TMO2 layer. First‐principles calculations suggest that oxygen loss in Na0.67Ni0.25Mg0.08Mn0.64Zr0.03O2 cathode is suppressed as Zr incorporation prevents the formation of oxygen vacancies. XPS analyses verify a Zr─O protective layer self‐segregated on particle surface during material synthesis. The expanded Na+ transport channel confirmed by the XRD analysis well explains the favored Na‐ion mobility verified by a high reversible capacity of 105.5 mAh/g at 20 C. This work sheds new light on providing a practical P2‐structured cathode material for high‐power sodium ion batteries.

The oxidation resistance of Ni nanoparticle incorporated SiOC coating for TiAl alloy

In this work, SiOC coatings incorporated with Ni nanoparticles were fabricated on γ-TiAl alloy by dip-coating. The microstructure and high temperature oxidation behavior of the SiOC-Ni coatings with different Ni contents were investigated. Results showed that the incorporation of Ni nanoparticles improved the oxidation resistance of the SiOC coating at 850 ℃. During thermal exposure to air, the incorporated Ni particles would react with both oxygen and the SiOC coating, forming NiO and Ni2Si, respectively, therefore changing the structure of the SiOC coating. The generation of NiO and Ni2Si is beneficial in reducing the oxygen partial pressure at the coating/substrate interface, thereby facilitating the formation of a protective aluminum oxide layer.

In situ p-block protective layer plating in carbonate-based electrolytes enables stable cell cycling in anode-free lithium batteries.

'Anode-free' Li metal batteries offer the highest possible energy density but face low Li coulombic efficiency when operated in carbonate electrolytes. Here we report a performance improvement of anode-free Li metal batteries using p-block tin octoate additive in the carbonate electrolyte. We show that the preferential adsorption of the octoate moiety on the Cu substrate induces the construction of a carbonate-less protective layer, which inhibits the side reactions and contributes to the uniform Li plating. In the mean time, the reduction of Sn2+ at the initial charging process builds a stable lithophilic layer of Cu6Sn5 alloy and Sn, improving the affinity between the Li and the Cu substrate. Notably, anode-free Li metal pouch cells with tin octoate additive demonstrate good cycling stability with a high coulombic efficiency of ~99.1%. Furthermore, this in situ p-block layer plating strategy is also demonstrated with other types of p-block metal octoate, as well as a Na metal battery system, demonstrating the high level of universality.

Robust Nitrogen/Sulfur Co‐Doped Carbon Frameworks as Multifunctional Coating Layer on Si Anodes Toward Superior Lithium Storage

AbstractSilicon (Si)‐based anodes hold great potential for next‐generation lithium‐ion batteries (LIBs) due to their exceptional theoretical capacity. However, their practical application is hindered by the notably substantial volume expansion and unstable electrode/electrolyte interfaces during cycling, leading to rapid capacity degradation. To address these challenges, we have engineered a porous nitrogen/sulfur co‐doped carbon layer (CBPOD) to uniformly encapsulate Si, providing a multifunctional protective coating. This innovative design effectively passivates the electrode/electrolyte interface and mitigates the volumetric expansion of Si. The N/S co‐doping framework significantly enhances electronic and ionic conductivity. Furthermore, the carbonization process augments the elastic modulus of CBPOD and reconstructs the Si‐CBPOD interface, facilitating the formation of robust chemical bonds. These features collectively contribute to the high performance of the Si‐CBPOD anodes, which demonstrate a high reversible capacity of 1110.8 mAh g−1 after 1000 cycles at 4 A g−1 and an energy density of 574 Wh kg−1 with a capacity retention of over 75.6% after 300 cycles at 0.2 C. This study underscores the substantial potential of the CBPOD protective layer in enhancing the performance of Si anodes, providing a pathway for the development of composite materials with superior volumetric energy density and prolonged cyclic stability, thereby advancing high‐performance LIBs.

Preparation and Properties of Waterborne Acrylic-Modified Epoxy Phosphate Resin and Its Coating

An acrylic acid-modified epoxy phosphate resin coating was synthesized by a four-step method marked “A-B-C-D”, and it was used as an efficient protective layer for steel structures. The coating exhibited good properties, mainly including water resistance (≥240 h), salt spray resistance (≥300 h), surface drying time (≤1 h), and adhesion (≥6.5 MPa).

Grain size effect on tribocorrosion kinetics in ultrahigh-purity magnesium

Tribocorrosion readily removes the protective corrosion product, creates new reactive corrosion sites and thus accelerates material loss in metallic materials. This is evidenced by a pronounced or gradual decline in open circuit potential (OCP) during tribocorrosion assessments. Here we report that grain refinement can not only enhance wear resistance in dry conditions, but also induce an anomalously stable OCP variation and fortify tribocorrosion resistance in ultrahigh-purity magnesium during tribocorrosion. The tribocorrosion tests revealed that the fine-grained Mg (FG-Mg) sample exhibited a wear rate (4.56 × 10−4 mm3/Nm) approximately half that of the coarse-grained Mg (CG-Mg) sample (7.87 × 10−4 mm3/Nm). CG-Mg showed a gradual OCP decrease, associated with a thin, unprotective tribocorrosion layer, even thinner than that resulting from dry sliding. Conversely, FG-Mg exhibited stable OCP evolution and quasi-linear tribocorrosion kinetics over time, attributed to a thick, protective tribocorrosion layer. Transmission electron microscopy data suggest that high-diffusivity pathways for oxygen along grain boundaries at the early tribocorrosion stages facilitate the formation of a continuous, protective MgO layer and an adjacent oxidized layer with a depth-dependent oxygen content gradient, enhancing tribocorrosion resistance in FG-Mg. Our findings offer valuable insights for strategically tailoring tribocorrosion resistance by modulating the OCP variation of highly active metals and alloys.

Nano‐ZnFe2O4 Facilitates Lithium Metal Anode Achieving High Stability

AbstractDue to its remarkably low redox potential and high specific capacity, the lithium metal anode has long been regarded as the ultimate choice for anode in lithium‐ion cells. However, its practical application has been impeded by two major challenges: poor Coulomb efficiency and the inevitable formation of lithium dendrites during charging/discharging processes. In this study, we propose a method to address these issues by fabricating a protective layer for the lithium metal anode using a polyethylene separator that has been modified with a composite of zinc nanoferrite and porous carbon (referred to as ZnFe2O4@PE). By employing this approach, we aim to achieve enhanced stability during anode cycling. The ZnFe2O4@PE serves multiple purposes. Firstly, it effectively reduces the local current density, thereby mitigating the drastic volume changes that occur during charging and discharging. Additionally, the nano‐ZnFe2O4 possesses a favorable affinity for lithium ions, facilitating their homogeneous deposition and suppressing the growth of lithium dendrites. As a result, the lithium metal anodes coated with the ZnFe2O4@PE protective layer exhibit excellent cycling stability, maintaining stable performance for 250 h. This innovative strategy offers a promising application pathway for lithium metal anodes.

Nafion/ZrO2 Modified NiTi Orthodontic Wire: Preparation, Material Characterization, and Corrosion Studies

Background: Nickel-titanium (NiTi) orthodontic wires are widely used in dental corrective procedures due to their high mechanical properties and cost-effectiveness. However, they are prone to oral corrosion, leading to mechanical deterioration, aesthetic issues, and potential health concerns. Objective: This study aims to improve the corrosion resistance and durability of NiTi orthodontic wires by employing zirconium dioxide (ZrO2) and Nafion coating with the goal of enhancing wire performance. Methods: Two types of NiTi wires were evaluated: a standard, unmodified wire as a control and another wire treated with electrodeposited ZrO2 film and Nafion (Naf) coating. Surface analysis was conducted using various techniques, including Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray Spectroscopy (EDX) analysis. Results: The uncoated NiTi wire exhibited a corrosion rate of 4.436× 10-1 mm/year, whereas the Naf/ZrO2-coated NiTi wire showed a corrosion rate of 4.068× 10-1 mm/year, indicating that the Naf/ZrO2 coating acted as a protective layer. Additionally, the ZrO2 layer provided poor electrical conductivity, resulting in slightly higher impedance compared to bare NiTi. The coating served as a barrier, which significantly enhanced corrosion resistance and improved the wire lifespan. Conclusion: Electro-modification through ZrO2 deposition and Nafion coating significantly improved the corrosion resistance and overall durability of NiTi orthodontic wires, offering a promising advancement for their use in dental orthodontics. This study underscores the potential of ZrO2 and Nafion coating to enhance the corrosion resistance and longevity of NiTi orthodontic wires.

The corrosion expansion force and cracking separation between corroded section steel arch frame and shotcrete in tunnel primary support

High chloride content in the subsea tunnel environment leads to inevitable corrosion of I-shaped steel in primary support. Corrosion generates expansive force between I-shaped steel and concrete, eventually cracking the concrete protective layer, and weakening the bond strength, severely impacting the tunnel support system’s durability. The main purpose of this article is to obtain the corrosion expansion force generated at the interface between corroded I-shaped steel and concrete, as well as the mechanical response characteristics of concrete under the action of corrosion expansion force. Firstly, nine I-shaped steel concrete components were fabricated for electro-accelerated corrosion test, obtaining the variation curve of corrosion expansion force with corrosion rate and protective layer thickness. The experimental results indicated that the development of corrosion expansion force can be divided into three stages: initial free corrosion stage (corrosion rate ρ = 0.5 % – 0.7 %), stage with a noticeable increase in corrosion expansion force (corrosion rate ρ = 0.7 % – 12 %), and expansion-induced cracking (corrosion rate ρ > 12 %). Meanwhile, a three-stage corrosion expansion force model for concrete and corroded I-shaped steel was proposed, which was correlated to the experimental curve well. Finally, the mechanical characteristics of the surrounding concrete during the development process of different corrosion expansion forces were explored through ANSYS software. The numerical results indicated that these cracks due to corrosion expansion force primarily occurring in the contact region between the concrete and the I-shaped steel flange, specifically in three areas: the central part of the flange and its two corners; The tensile stress in the concrete surrounding the web plate is less than that at the flange, leading to the initial longitudinal cracking observed on the outer surface of the flange.

Effects of laser shock peening on silicon nitride ceramic with varying sintering additive ratios

Silicon nitride ceramic (Si3N4) for industrial applications is conventionally manufactured with sintering additives, and the properties of Si3N4 change significantly based on the contents of these additives. In this study, we investigate the effects of laser shock peening (LSP) on Si3N4 sintered with varying ratios of sintering additives.The Si3N4 samples were sintered with a mixture of Y2O3, MgO, and SiO2 sintering additives at 5, 7, 9, and 11 wt%. A Nd:YAG laser (wavelength = 532 nm, maximum pulse energy = 1.4 J, repetition rate = 10 Hz, pulse duration = 8 ns, beam diameter = 11 mm, top-hat profile) was used to irradiate the Si3N4 samples. The samples were coated with a protective layer (100 μm thick aluminum foil) and a water layer to confine plasma. LSP of Si3N4 with 5% sintering additives resulted in a slight change in surface hardness but a 77% decrease in surface compressive residual stress. In contrast, LSP of Si3N4 with 11% sintering additives led to a simultaneous increase in surface hardness (7.3%) and surface compressive residual stress (67%), indicating a significant difference in the effectiveness of LSP depending on the ratio of sintering additives. Additionally, the surface of Si3N4 with 11% sintering additives showed evidence of grain refinement after LSP. It was demonstrated that the bending strength of Si3N4 with 11% sintering additives increased by 15.2%, and the depth of the fracture origin was significantly deepened.

Study of ultrasonic parameters for quality monitoring of plate heat exchanger

Abstract Heat exchangers are crucial heat transfer devices widely used in energy industries such as power generation, oil production, and engine cooling. The plate heat exchanger is one of the most economical and efficient types of exchangers. It transfers heat using metal plates and has a high heat transfer efficiency because the fluid is exposed to a higher plate surface area. However, due to the presence of dissolved or suspended particles in the heat-exchanging fluids, a layer of deposit (fouling layer) is formed on the heat exchanger plates. It results in reduced efficiency of the device. Thus, a common cleaning method, such as chemical-based or manual methods, is employed. However, it always poses a risk of over-cleaning or removal of the protective oxide layer. Thus, an efficient mechanism to monitor the onset of the fouling layer would greatly help to achieve increased efficiency and cost reduction in the cleaning of the plates. Recent advances show ultrasound as one of the promising non-destructive inspection techniques to monitor the growth of the fouling layer. However, the variation in heat-exchanging fluid temperature affects the investigated acoustical parameter measurement. Thus, this research aims to study the linear and nonlinear ultrasonic parameters incorporating temperature-dependent effects from the fluid to provide an accurate real-time monitoring tool. The nonlinear acoustics analysis is experimentally employed in the research using the Second harmonic generation method (SHGM). The proposed research will help design ultrasound-assisted plate heat exchangers for maximum heat transfer efficiency.

High temperature oxidation resistance behavior of Ti3SiC2/Cu composites under migration of Ti and Cu atomic

The oxidation behavior and oxidation mechanism of Ti3SiC2/Cu composites were investigated using constant temperature oxidation method. The Ti3SiC2/Cu composites were prepared at different sintering temperatures. Results showed that the relationship between the oxidation reaction rate of Ti3SiC2/Cu composites in air at 700°C∼900°C and the oxidation temperature was in accordance with the parabolic law of oxidation kinetics. The oxidation weight gain and oxide layer thickness of Ti3SiC2/Cu composites at 700 °C and 800 °C were insignificant, with oxidation reaction rates of 3.0692×10-9 kg2m-4h-1 and 6.9856×10-9 kg2m-4h-1, respectively, and the oxidation rate of Ti3SiC2/Cu composites at 900 °C was enhanced to 1.00907×10-8 kg2m-4h-1. Ti3SiC2/Cu composites oxidized at 900°C formed a protective oxide layer, which was mainly a multilayer structure composed of different kinds of oxides: the outer layer was mainly composed of TiO2; the intermediate layer mainly consisted of CuO; the inner layer mainly made up of TiO2 and SiO2.

Scalable Fabrication of Black Phosphorous Films for Infrared Photodetector Arrays.

Bulk black phosphorous (bP) exhibits excellent infrared (IR) optoelectronic properties, but most reported bP IR photodetectors are fabricated from single exfoliated flakes with lateral sizes of <100µm. Here, scalable thin films of bP suitable for IR photodetector arrays are realized through a tailored solution-deposition method. The properties of the bP film and their protective capping layers are optimized to fabricate bP IR photoconductors exhibiting specific detectivities up to 4.0×108cm Hz1/2 W-1 with fast 30/60 µs rise/fall times under λ = 2.2µm illumination. The scalability of the bP thin film fabrication is demonstrated by fabricating a linear array of 25 bP photodetectors and obtaining 25×25pixel IR images at ≈203ppi with good spatial fidelity. This research demonstrates a commercially viable method of fabricating scalable bP thin films for optoelectronic devices including room temperature-operable IR photodetector arrays.

Oxidation of Sintered Refractory Alloy (Ni3Al)

Ni3Al is a superalloy which is of particular interest at high temperatures due to its high resistance to oxidation with the formation of a protective oxide layer that performs better than NiO and Cr2O3. Among the factors likely to affect the reaction mechanism and modification of the oxidation kinetics, the surface state appears to be a very important parameter. In the case of sintered materials, the surface condition will be linked to the porosity of the material and therefore to densification. This work essentially has two parts. The first consists of developing Ni3Al sinters intended for oxidation, studying the densification mechanisms and bringing together the results obtained by dilatometry at variable temperature and by differential thermal analysis which made it possible to demonstrate sintering in a reactive liquid phase extremely fast SHS type, with instantaneous formation of the Ni3Al phase. The second part is devoted to the isothermal oxidation between 1100 and 1350°C of cubic-shaped sinters (4mm edge) under a flow of oxygen for 24 hours. The shape of the parabolic curves is correlated with morphological and microstructural observations to deduce the diffusional kinetic regime which controls the speed of the reaction. On the other hand, these observations highlighted a very strong adhesion due to the indentations of the Al2O3 oxide in the metal at the oxide/metal interface. Various techniques (Density – XRD – SEM and Microanalysis) to characterize the sinters and the oxidation products complete our study.

Rapid calibration plan for NIF's Near Backscatter Imager (NBI).

A rapid calibration system is under development for the Near Backscatter Imager (NBI) in use at the National Ignition Facility (NIF). NBI is an optical diagnostic that quantifies the stimulated Brillouin and Raman backscatter produced by NIF's targets. Specifically, NBI measures the light that does not fall directly back into the laser aperture, which is measured by the Full Aperture Backscatter System (FABS). When working in tandem with FABS, NBI allows for the full characterization of backscattered light. This informs Hohlraum laser coupling, optical damage, and laser-plasma interaction models. NBI uses a large Spectralon plate covered by a protective glass layer and is mounted inside the target chamber where it is exposed to high energy backscatter, neutrons, and build-up debris left over from the exploded targets. This gradually alters the reflectivity of the plate, meaning that NBI needs to be calibrated regularly. Described here is NIF's design for a system capable of rapid in situ calibration of NBI that is to be installed in FY25.

Development of electrode and electrolyte materials for solid-state batteries based on Li1.3Al0.3Ti1.7(PO4)3

The dependence of the electrochemical characteristics of a layered cathode material containing LiNi0.5Mn0.3Co0.2O2 on the method for applying a protective layer of nanoparticles of the lithium-conducting material Li1.3Al0.3Ti1.7(PO4)3 with a NASICON structure to its surface has been studied. The surface modification has been found to improve the capacity retention in prolonged charge/discharge cycling (up to 15%) and to allow fast charge/discharge processes. The possibility of using a composite electrolyte consisting of a porous ceramic matrix of aluminum-substituted lithium titanium phosphate Li1.3Al0.3Ti1.7(PO4)3 with a transition layer of liquid electrolyte LP-71 has been shown. The use of a thick composite solid electrolyte results in a slight reduction (∼5–7 mAh g−1) in initial capacity compared to laboratory cells with the widely used Celgard 2400 separator impregnated with liquid electrolyte. Laboratory cells assembled with a composite electrolyte showed higher stability during charge/discharge cycling: after 80 deep charge/discharge cycles, the capacity reduction was ∼12% for cells with a composite electrolyte, while for the reference cell it was ∼23%.

Investigation of Rosemary Oil as Environmentally Friendly Corrosion Inhibitor of Aluminum Alloy

The inhibitory effect of Rosemary oil on the corrosion of aluminum alloy EN AW-2011 in 1M H2SO4 solution was studied by weight loss and electrochemical methods such as open circuit potential (OCP), linear sweep voltammetry (LSV) and linear polarization resistance (LPR). The inhibition efficiency increases with increasing the concentration and shows maximum inhibition efficiency (70.7 %) at optimum concentration (0.05 g.L-1). The linear polarization resistance measurements show that the presence of Rosemary oil in 1M H2SO4 solution influences polarization resistance increasing and corrosion current decreasing. The voltammetric curve shows that Rosemary oil reduces the anodic process. Open circuit potential results confirmed that organic compounds present in Rosemary oil can form a protective layer on aluminum surfaces. The inhibitive effect was probably caused by the adsorption of organic compounds such as 1,8-cineole, α-pinene, borneol, limonene, and myrcene on aluminum surfaces which are non-toxic and environmentally friendly. This study showed that the essential oil of Rosemary could be used as an environmentally friendly inhibitor of the corrosion of alloy EN AW-2011 in an acidic medium.