Browse Topic: Corrosion

Items (7,226)
Corrosion of prestressed tendons endangers the safety of bridges, but until now, there has been no effective method to solve the problem of detecting corrosion damage in prestressed tendons of concrete beams. To address this, a magnetic flux leakage detection experimental apparatus for corrosion damage in prestressed tendons based on the principle of magnetic flux leakage inspection has been developed. Using this apparatus, magnetic flux leakage tests were conducted on prestressed tendons after electrochemical corrosion, and the results were compared with simulation analysis to conduct a comparative study. In the experiments, the influence of corrosion severity, corrosion width, and the effect of stirrups on the characteristics of the magnetic flux leakage signals were studied. Magnetic signal feature values were extracted, and a quantification neural network model for corrosion damage was established, which is used to quantify the degree of corrosion damage in prestressed tendons. The
Wang, PengGao, MinDong, LeiZhu, Junliang
The half-through arch bridge, known for its efficient structural design and seamless integration with the surrounding environment, is widely utilized in urban transportation infrastructure. However, during operation, the hangers of the through and half-through arch bridge are exposed to various factors, including environmental conditions and cyclic traffic loads, which often cause the hanger of these bridges to rust and fracture, will lead to structural damage or even the collapse of the entire bridge. Therefore, investigating the dynamic performance of half-through arch bridges, both before and after hanger damage, under vehicle-bridge coupling is of paramount importance for understanding the overall performance of the bridge. In this study, a half-through arch bridge was selected as the subject of investigation. A three-dimensional finite element model of the bridge was developed based on real-world engineering projects, and a numerical simulation of the vehicle-bridge coupling
Chen, XiaobingJi, Wei
This paper analyzes the potential of combining natural fibers with nanomaterials to develop advanced composites for automotive sector applications, providing a sustainable alternative to parts traditionally produced with metallic materials. The metallic alloy in the automotive industry is widely used in vehicle manufacturing, but faces significant challenges, such as high production costs, high weight, susceptibility to corrosion, and rigorous recycling processes. Natural fibers stand out for favorable mechanical properties, low cost, low weight, and eco-friendly material, making promising alternatives to metals and synthetic fibers. The combination of natural fibers and nanomaterials creates composites with improved mechanical and thermal, reducing any limitations inherent to natural fibers. Therefore, composites combined, called hybrid, have a high potential for use in various automotive components, such as in structural and non-structural applications. This study also analyzes the
Corrêa, KarythaCabral, GabrielSantiago, MarceloVeloso, VerônicaChaves, Matheus
The application of Thermal Barrier Coatings (TBC) has been widely utilized in aerospace turbines to enhance the operational temperature and thermal efficiency of titanium alloys, while preserving their properties such as low density, creep resistance, and corrosion resistance. TBC systems typically consist of a metallic substrate, a metallic coating (Bond Coat), a thermally grown oxide (TGO), and a ceramic topcoat (TC). This study investigated the fracture surface characteristics of Ti-6Al-4V with TBC after a creep test at a constant temperature of 600 °C, under stress levels of 125, 222, and 319 MPa, in order to understand the mechanisms involved. The TBC was composed of a NiCrAlY (BC) and a zirconia co-doped with yttria and nióbia (TC). The fracture characterization of the alloy after the creep test was conducted through stereoscopy and scanning electron microscopy. The fracture mechanism at 600 °C and 222 MPa was predominantly ductile, as evidenced by the presence of dimples and
Takahashi, Renata Jesuinade Assis, João Marcos KruszynskiRodrigues, Bianca Costade Andrade Acevedo Jimenez, Laila RibeiroReis, Danieli Aparecida Pereira
The study focuses on the management of deep foundation pit excavation, influenced by temporal and spatial factors, in the context of the challenging environmental circumstances posed by the high-water-level silty soft clay along the Yellow River's northern shore, as part of the Jinan urban rail transit initiative. The subsequent inferences have been made: (1) Throughout the digging phase, issues such as excessive digging and delays in installing steel reinforcements occur, while the subterranean diaphragm wall tends to shift significantly inward within the excavation area due to the disparity in pressure between the water and soil inside and outside. (2) During the building phase, managing wall distortion is imperative, and an enhanced preliminary force should be applied to the support's axial component at points of significant deformation, guaranteeing an excess coefficient for both the support rigidity and the continuous subterranean wall rigidity. (3) In the process of diaphragm
Gao, TiangangZhang, XuPan, FuyongZhang, Wenjun
Compared to steel, aluminum alloy has the advantages of light weight, high specific strength, corrosion resistance, and easy processing, and is widely used in structures such as aviation, construction, bridges, and offshore oil platforms. All along, Chinese construction aluminum profiles have been produced according to the GB/T5237-XXXX standard, which is determined based on the mechanical performance requirements of doors and windows and the actual processing of aluminum profiles. There are many problems. The author of this article has developed a new product 6063-T56, which has a tensile strength of 240-260Mpa and an elongation rate of not less than 8%, surpassing the latest technology level in Europe. It has been promoted and applied to the aluminum profile production industry in China, improving product performance, reducing production costs, improving production efficiency, and meeting the requirements of the "Aluminum Alloy Doors and Windows Standard" GB/T8478-2020, making
Qiao, Zhou
Producing 3D models of cooling water passages of outboard motors, and calculating distribution of electric potential on the water passage surfaces using BEM, we have developed the new method for simulation of electric potential distribution. The outboard motor is a propulsion system attached to the transom of the boat with steering function. As the water around the boat is drawn in for cooling of the engine, the engine parts are susceptible to severe corrosion. As a means to help prevent corrosion, a part referred to as the anode metal, which has a lower natural potential, is provided. Such a method is called the sacrifice protection because the anode metal corrodes before the engine parts due to the difference of electric potential. Since anti-corrosion currents occur preferentially to areas close to the anode metal, the anode metal is required to be located at the most effective place for corrosion protection. However, there are certain restrictions in the layout of anode metal from
Shibuya, RyotaSuzuki, Hiroki
With the rise of prefabricated metro stations in metro construction, the selection of its block type has become a key issue under specific stratigraphic conditions. In this paper, three types of prefabricated metro stations (Type 1, Type 2 and Type 3) are studied in the stratum of a metro station in Shenzhen as an example. Through MIDAS GTS NX, a single-ring stratum-structure model is established and the same calculation step is set to analyse the mechanical response of precast component assembly to the concrete at the bottom of the pit and the bottom slab. In terms of the concrete at the base of the footing, the stress of Type 3 has an advantage but the overall fluctuation is complicated, the stress of Type 2 fluctuates greatly and the stress of some nodes is high, and the change of Type 1 is relatively smooth; in terms of deformation, Type 2 and Type 3 settle symmetrically, and the influence of Type 2 is small. For precast structural base plate, stress on type 3 part of the stage of
Xie, JunJiang, WeiFan, XiaominZheng, PengpengHuang, ZhumingYang, Zhao
This specification covers flash welded rings made of corrosion and heat-resistant austenitic steels and austenitic-type iron, nickel, or cobalt alloys, or precipitation-hardenable alloys.
AMS F Corrosion and Heat Resistant Alloys Committee
Advanced ferritic nitrocarburizing process combined with a specialized post-oxidation treatment described as FNC + Smart ONC® [1] is developed for brake rotor applications. The process can be applied to standard grey cast iron brake rotors, significantly reducing PM 10 emissions to levels below the Euro 7 limits for most vehicles equipped with at least some recuperative braking capabilities, all without compromising performance. Finished grey iron brake rotors, ferritic nitrocarburized and post oxidized were evaluated according to several industry standards. The standards include SAE J2707B (Block Wear Test including Highway) [2], GRPE-90-24 Rev.1 Emission Test (Full WLTP Brake Cycle 6 Times) [3], and SAE J2522 (AK-Master Performance) [4]. Nitrocarburized post oxidized brake rotors were compared to untreated grey iron rotors exposed to several friction materials. Ferritic nitrocarburizing and post oxidation addresses the issue of corrosion, which is particularly relevant for brake
Winter, Karl-MichaelHolly, Mike
This study investigates the correlation between moisture behavior and corrosion stiction mechanisms in NAO friction materials. While previous studies on corrosion stiction have primarily focused on electrochemical approaches, this study aims to elucidate the mechanism by examining moisture behavior within the friction material. Although recent research has investigated changes in pad properties in humid environments, most studies have primarily focused on variations in pad stiffness and the friction coefficient. To date, no studies have investigated the behavior of moisture within pads using Fick’s Second Law and its impact on corrosion stiction. In this study, Fick’s Second Law was applied to model moisture behavior in friction materials. The diffusion coefficient and maximum moisture content were quantified, revealing that moisture behavior in the friction material can be divided into two distinct stages: one following Fick’s Second Law and the other not. For NAO friction materials
Choi, NakcheonJu, JoungsuYoun, Deokki
This specification covers an aluminum alloy in the form of extruded bars, rods, and profiles (shapes) from 0.375 to 1.300 inches (9.53 to 33.02 mm) in diameter or thickness, produced with cross-sectional area of 22.5 square inches (145 cm2), maximum, and a circumscribing circle diameter (circle size) of 17.4 inches (44.2 cm), maximum (see 2.4 and 8.8).
AMS D Nonferrous Alloys Committee
This specification, in conjunction with the general requirements for steel heat treatment in AMS2759, establishes requirements for thermal stress-relief treatments of parts manufactured from the following materials: a Carbon and low-alloy steels b Tool steels c Precipitation-hardening, corrosion-resistant, and maraging steels d Austenitic corrosion-resistant steels e Martensitic corrosion-resistant steels
AMS E Carbon and Low Alloy Steels Committee
This specification covers a corrosion- and heat-resistant cobalt alloy in the form of welding rods or wrought wire.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet, strip, and plate 0.002 inch (0.05 mm) and above in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet and strip over 0.005 inch (0.13 mm) in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion- and heat-resistant steel in the form of sheet, strip, and plate over 0.005 inch (0.13 mm) in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion- and heat-resistant nickel alloy in the form of sheet, strip, and plate up to 1.000 inch (25.40 mm) in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a high-strength, corrosion-resistant alloy in the form of bars up to 1.75 inches (44.4 mm) in diameter (see 8.2).
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a high-strength, corrosion-resistant alloy in the form of bar up to 1.75 inches (44.4 mm) in diameter (see 8.2).
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers an iron-nickel alloy in the form of strip 0.020 to 0.1874 inch (0.51 to 4.760 mm), inclusive, in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet, strip, and foil.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers an aluminum alloy in the form of plate 0.250 to 4.000 inches (6.35 to 101.60 mm), inclusive, in thickness (see 8.6).
AMS D Nonferrous Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet and strip over 0.005 inch (0.13 mm) in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet and strip over 0.005 inch (0.13 mm) in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers grease for use on aircraft wheel bearings. It also defines the quality control requirements to assure batch conformance and materials traceability and the procedures to manage and communicate changes in the grease formulation and brand. This specification invokes the Performance Review Institute (PRI) product qualification process. Requests for submittal information may be made to the PRI at the address in 2.2, referencing this specification. Products qualified to this specification are listed on a qualified products list (QPL) managed by the PRI. Additional tests and evaluations may be required by individual equipment builders before a grease is approved for use in their equipment. Approval and/or certification for use of a specific grease in aero and aero-derived marine and industrial applications is the responsibility of the individual equipment builder and/or governmental authorities and is not implied by compliance with or qualification to this
AMS M Aerospace Greases Committee
This specification covers a corrosion-resistant steel in the form of sheet and strip over 0.005 inch (0.13 mm) in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers grease for use within an aircraft. It also defines the quality control requirements to assure batch conformance and materials traceability and the procedures to manage and communicate changes in the grease formulation and brand. This specification invokes the Performance Review Institute (PRI) product qualification process. Requests for submittal information may be made to the PRI at the address in 2.2, referencing this specification. Products qualified to this specification are listed on a Qualified Products List (QPL) managed by the PRI. Additional tests and evaluations may be required by individual equipment builders before a grease is approved for use in their equipment. Approval and/or certification for use of a specific grease in aero and aero-derived marine and industrial applications is the responsibility of the individual equipment builder and/or governmental authorities and is not implied by compliance with or qualification to this specification.
AMS M Aerospace Greases Committee
This specification covers a corrosion-resistant steel in the form of cold-worked bars and wire up to 1.750 inches (44.45 mm), inclusive, in nominal diameter or least distance between parallel sides.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet and strip 0.005 inch (0.13 mm) and over in nominal thickness.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers a corrosion-resistant steel in the form of sheet and strip.
AMS F Corrosion and Heat Resistant Alloys Committee
There is a critical need to understand and optimize the extrudability of AA6xxx alloys, which are widely used in industries such as automotive and aerospace due to their favorable combination of strength, formability, and corrosion resistance. Surface cracking during the extrusion process remains a significant challenge, compromising the material’s mechanical properties and product quality. While previous studies have investigated surface cracking using various techniques, the underlying mechanisms remain elusive, especially regarding the role of important alloying elements such as copper. Therefore, this research provides a thorough investigation of the effect of copper additions on the solidus temperature, hot deformation behavior, and extrudability of AA6xxx alloys. Using experimental and numerical methods, the material’s solidus temperature and constitutive behavior were determined. Extrusion trials were conducted for alloys with different copper levels using a flat die over a
Wang, XiaoyingShehryar Khan, MuhammadWells, Mary A.Poole, Warren J.Parson, Nick
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
This specification covers a corrosion- and heat-resistant nickel alloy in the form of bars, forgings, flash-welded rings, and stock for forging, flash-welded rings, or heading.
AMS F Corrosion and Heat Resistant Alloys Committee
This specification covers an aluminum alloy in the form of plate 3.000 to 6.000 inches (76.20 to 152.40 mm), inclusive, in nominal thickness (see 8.5).
AMS D Nonferrous Alloys Committee
As a carbon-free molecule, ammonia is more and more considered as a relevant fuel for long distance and off-road applications. However, this gas has different combustion characteristics compared to conventional fuels, challenging the suitability of lubricants to such engines. In this work, the evolution of lubricants under conditions mimicking ammonia combustion was assessed. Mineral and polyester lubricant base oils were exposed to oxygen, nitrogen oxides, and ammonia in a pressurized reactor under stirring. Oil aliquots were sampled at regular intervals, and characterized using Fourier Transform Infrared Spectroscopy (FTIR), viscosity and total oxygen and nitrogen contents measurements. Exposure to air containing nitrogen oxides resulted in quicker accumulation of oxidation products compared to neat air, for both the mineral and complex polyester base oil. Besides, exposure to gaseous ammonia in air resulted in a slower oxidation rate for both oils, compared to neat air. A global
Doncoeur, CaroleGiarracca, LuciaCologon, PerrineRousselle, Christine
The aim of this work is to present the overviewing results of the low friction coating technology for modern automotive application with the themes, e.g. electric vehicle (EV), R&D trends and bioethanol fuel application. According to Forbes, China, armed with EV, could have several companies among the top 10 global brands by sales in 2030. EV’s friction is more severe than traditional powertrain friction. For the protection of EV’s wear and friction, the coatings, diamond like carbon (DLC) and CrCuN, are compared in the literature. Global coating companies developed with the keywords: hybrid process, low-temperature coating process for polymer material. Last coating conferences showed R&D trends: coating for polymer materials, tetrahedral amorphous carbon (taC) coating, low-temperature coating process and multi-elements containing coatings. In Korea, research institutions, universities and Hyundai Motor Group have a long-term project for the development of ultralow friction coatings of
Cha, Sung ChulMoon, Kyoung IlKim, JongkukPark, Chang HoKim, Dong Sik
A pacemaker is a small device that helps control your heartbeat so you can return to your normal life. It has three main parts: a pulse generator that creates electrical signals, a controller-monitor that manages these signals, and leads that deliver the signals to the heart. One key benefit of the pacemaker is its strong titanium casing. Titanium is very strong and lightweight, and it is biocompatible, meaning it works well with the body without causing harmful reactions. This metal is highly resistant to corrosion, which helps keep the casing intact and protective even when exposed to bodily fluids.
Aqueous zinc-ion batteries (ZIBs) have attracted extensive attention due to their high safety, abundant reserves, and environmental friendliness. Iodine with high abundance in seawater (55 μg L-1) is highly promising for fabricating zinc-iodine batteries due to its high theoretical capacity (211 mAh g-1) and appropriate redox potential (0.54V). However, the low electrical conductivity of iodine hinders the redox conversion for an efficient energy storage process with zinc. Additionally, the formed soluble polyiodides are prone to migrate to the Zn anode, leading to capacity degradation and Zn corrosion.
In electrified drivetrains, lubricants are commonly in contact with the motor and other electrical components as well as the gears and bearings. Copper, present in these electrical components, is susceptible to corrosion by fluids containing active sulfur, which can lead to catastrophic failure of the unit. Lubricating fluids for electric vehicles (referred to as e-fluids) must not cause corrosion and must maintain high performance while having suitable electrical conductivity, material compatibility, and heat transfer properties. We describe a new formulation without active sulfur that has recently entered the market, which can protect against copper corrosion. We show that this e-fluid can provide suitable wear protection under field trial conditions, and that the e-fluid provides improved wear protection in bearing (FE-8) tests compared to a traditional extreme pressure axle fluid (API GL-4). Surface analysis (X-ray photoelectron spectroscopy) measurements of the component surfaces
Hopper, Elizabeth R.Williams, Megan S.Gahagan, Michael
Southwest Research Institute is working to expand software normally used to model electrolytes and predict corrosion and turn it into a tool that can help determine whether ice-covered worlds have the right conditions for microbial life. The project is supported by NASA’s Habitable Worlds program, which seeks to use knowledge of the history of the Earth and the life upon it as a guide for determining the processes and conditions that create and maintain habitable environments.
Reducing CO2 emissions is now a major focus in India heading towards net zero emissions by 2070. India is the 3rd largest automobile market in the world and the transportation sector is the 3rd largest CO2 emitter. In this direction, it is necessary to reduce the carbon footprint from the automobile sector to combat climate change. The adoption of sustainable biofuels such as ethanol will enable us to reduce emissions, as ethanol is carbon neutral fuel. However, vehicle manufacturers are facing challenges in manufacturing flex fuel compatible parts in the vehicle mainly fuel systems. Ethanol has both nonpolar and polar bonds, making it miscible to both gasoline and water, thereby water contamination is inevitable in ethanol blend fuels. In addition, control of ethanol contamination by sulfates and chlorides during ethanol production is challenging. Thus, ethanol blend fuels are considered more corrosive and tendency towards deposit formation than normal gasoline fuels. Design and
Pandi, Dinesh BabuShanmugam, Gomathy PriyaNagarkatti, ArunGopal, ManishAnbalagan, Prathap
Gray cast iron is a cost-effective engineering material widely used for heavy duty engine blocks and brake rotor discs in vehicles. Thermomechanical fatigue (TMF) frequently occurs during vehicle operation due to temperature fluctuations in brake rotors. To speed up the design of the component, design structurally sounding brake rotors, and prevent premature thermally induced cracking, it is critical to investigate TMF behavior of the gray cast iron. This study presents a series of fatigue tests, including isothermal low cycle fatigue (LCF) tests at temperatures up to 700°C, as well as in-phase (IP) and out-of-phase (OP) TMF tests across various temperature ranges. Because of the asymmetric behavior in tension and compression, creep behaviors in both tension and compression and oxidation are also studied. These behaviors are the key to enable simulation of thermally induced cracks in rotors.
Liu, YiLee, HeewookHess, DevinCoryell, Jason
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