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Wyniki wyszukiwania dla: corrosion, hull steels, acoustic emission, corrosion tester
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Application of the corrosion tester in corrosion tests using the acoustic emission method.
PublikacjaThe article presents an innovative method of corrosion tests using the acoustic emission method and the corrosion tester. The problem of corrosion occurring in ballast tanks and tanks carrying petroleum products is discussed. The acoustic method is presented which, due to the use of a unique corrosion tester, is used to monitor the course of corrosion processes in steel. The principle of operation of the corrosion tester, its construction...
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The evaluation methodology of corrosion protection of tanks from hull structural steels with Acoustic Emission use and first results of investigations
PublikacjaW referacie przedstawiono metodykę badań mającą na celu ocenę stopnia ochrony przed korozją konstrukcji zbiorników ładunkowych i balastowych wykonanych ze stali kadłubowych z wykorzystaniem Emisji Akustycznej (EA). W metodyce wykorzystano wymagania obowiązujących norm, standardów oraz doświadczenia zdobyte w dotychczasowych badaniach poświęconych zastosowaniu metody EA do wykrywania i lokalizacji źródeł korozji na statkach. Do...
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Monitoring of underdeck corrosion by using acoustic emission method
PublikacjaThis paper presents first short characteristics of underdeck corrosion process as well as a problem of its monitoring. Next is described an acoustic emission (AE) method elaborated by Department of Ship Technology , Quality Systems and Material Engineering, Gdańsk University of Technology in cooperation with partners of CORFAT project realized within 7th EU Frame Program . Further are presented short characteristics of the emission...
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Electrochemical and acoustic emission studies of aluminum pitting corrosion
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Electrochemical and acoustic emission studies of aluminium pitting corrosion
PublikacjaBadania metodą potencjokinetyczną i emisjii akustycznej przeprowadzono w typowej trójelektrodowej celce elektrochemicznej. Elektrodę badaną przygotowano z stopu aluminium 1050A. Badania metodą cyklicznej polaryzacji i emisjii akustycznej wykonywano jednocześnie. Na podstawie wyników akustycznych i polaryzacyjnych wyznaczono potencjał korozji wzerowej.
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Application of acoustic emission in evaluation of pitting corrosion insteel
PublikacjaPrzedstawiono przegląd różnych zastosowań emisji akustycznej (AE) w badaniach korozji wżerowej stali austenitycznej. Wykorzystanie emisji akustycznej w przypadku tego rodzaju korozji nie jest przypadkowe, ponieważ korozja wżerowa jest najgroźniejszym typem korozji, atakującym różne materiały konstrukcyjne takie jak stal. Prezentowana praca przeglądowa dostarcza przydatnych informacji o naturze pomiarów akustycznych, które wykazują...
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Investigations of pitting corrosion of magnesium by means of DEIS and acoustic emission
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Investigation of pitting corrosion of stainless steel by means of acoustic emission and potentiodynamic methods
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Detection of corrosion process in marine environment by means of acoustic emission technique
PublikacjaW pracy przedstawiono możliwość detekcji procesu korozyjnego nieniszczącą metodą emisji akustycznej konstrukcji metalowych pracujących w środowisku wody morskiej. Pewną alternatywą wobec technik elektrochemicznych w monitorowaniu korozji zaproponowano nieniszczącą technikę emisji akustycznej. Emisja akustyczna znana jako zjawisko fizyczne i technika pomiarowa znalazły zastosowanie w detekcji korozji obiektów morskich. W związku...
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Detection and localisation of corrosion process effect by means of acoustic emission technique
PublikacjaW pracy przedstawiono możliwość wykorzystania techniki emisji akustycznej do detekcji i lokalizacji skutków procesu korozyjnego - wycieku. Wyniki badań wykonanych w warunkach laboratoryjnych, zbliżonych do rzeczywistych, potwierdziły akustyczne wykrycie oraz ustalenie położenia wycieku. Położenie wycieku obliczono również na podstawie techniki interkorelacji i porównano z lokalizacją uzyskaną bezpośrednio z pomiarów akustycznych....
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Acoustic Emission Monitoring of Structural Elements of a Ship for Detection of Fatigue and Corrosion Damages
PublikacjaUszkodzenia korozyjne i pęknięcia zmęczeniowe są głównymi przyczynami defektów strukturalnych we wszystkich środkach transportu takich jak statki, cysterny drogowe i kolejowe. Oba typy degradacji tzn. degradacja materiału i konstrukcji są przedmiotem badań przeprowadzanych w projekcie badawczym VII Programu Ramowego Unii Europejskiej o nazwie ''Monitorowanie efektywnych kosztów korozji i zmęczenia w środkach transportu'' (akronim...
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Experimental study of corrosion in reinforced concrete by acoustic emission and electrochemical noise techniques
PublikacjaTechnika emisji akustycznej jest znaną metodą badań korozji zbrojenia żelbetu. Źródłem aktywności akustycznej są zawsze zjawiska o naturze mechanicznej. Przedstawiono wynik badań akustycznych zbrojonego betonu w warunkach polaryzacji anodowej, przyspieszającej procesy korozyjne. Symultanicznie prowadzona była rejestracja szumu elektrochemicznego. Dla umożliwienia korelacji wyników, uzyskanych obiema technikami, wykonana została...
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Results of acoustic emission tests of corrosion protection degree of ship steel tanks covered by means of protective coatings (Phase I)
PublikacjaThis paper presents methods and results of the 1st series of tests of acoustic emission (AE) signals, aimed at assessing degree of corrosion protection of a tank made of hull structural steel, protected by means of a protective coating combined from polyurethane layer and concrete filler. The tests were carried outin compliance with a method specially elaborated for application to the work in question. In the method were used requirements...
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Instantaneous impedance monitoring of AA 7075 aluminum alloy corrosion in borate buffer with admixed chloride ions
PublikacjaThe study presents a research capabilities of Dynamic Electrochemical Impedance Spectroscopy (DEIS) as a tool used for instantaneous on-line monitoring of corrosion processes on the example of AA 7075 aluminum alloy. A borate buffer with admixed chloride ions in a quantity ranging from 0.05 to 25 mM was used to represent different types of corrosion attack. The surface of samples specimens was evaluated before and after the tests...
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The Influence of Gas Mixture in the Glow-Discharge Nitriding Process of Austenitic Stainless Steel on Characteristic of Nitrided Cases
PublikacjaAustenitic stainless steels characterize with excellent corrosion resistance, although low mechanical properties. In many cases that limits their exploitation in industrial applications. Moreover, austenitic stainless steel is susceptible to local corrosion in the presence of halide ions. In present works, it was emphasized that the nitriding of austenitic stainless steels gives some potential abilities to obtain beneficial effect...
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Wpływ azotowania jarzeniowego i laserowego nadtapiania na odporność kawitacyjną stali X5CrNi18-10
PublikacjaNierdzewne stale austenityczne charakteryzują się doskonałą odpornością korozyjną, aczkolwiek niskimi właściwościami mechanicznymi. W wielu przypadkach ogranicza to ich eksploatację w warunkach przemysłowych. Ponadto, nierdzewne stale austenityczne są wrażliwe na korozję lokalną w obecności jonów halogenkowych. Technologie materiałowe, które dają potencjalne możliwości otrzymywania korzystnego wpływu na właściwości mechaniczne...
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Corrosion of evaporator tubes in low emission steam boilers
PublikacjaPurpose of this paper is to reveal the mechanisms of corrosion processes of outer surfaces of low-emission steam boiler evaporator tubes. Examinations were performed to find the reasons of different corrosion susceptibility of tubes situated at combustion chamber on various levels. Examinations were conducted on several segments of 57 x 5.0 mm evaporator tubes made of 16M (16Mo3) steel grade. Segments were taken from level of...
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A methodology for ultimate strength assessment of ship hull girder accounting for enhanced corrosion degradation modelling
PublikacjaThe presented work shows a methodology for the ultimate strength assessment of a ship hull, considering enhanced corrosion modelling. The approach is based on the classical Smith method. However, the recent findings regarding the impact of corrosion degradation on ultimate strength are incorporated. To this end, the stress–strain relationships for particular elements composing ship hull cross-section are modified using a specially...
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Analysis of features of stainless steels in dissimilar welded joints in chloride inducted corrosion
PublikacjaStainless steels of femtic-austenitic microstructure that means the duplex Cr-Ni-Mo steels, in comparison with austenitic steel includes less expensive nickel and has much better mechanical properties with good formability and corrosion resistance, even in environments containing chloride ions. Similar share of high chromium ferrite and austenite, which is characterized by high ductility, determines that the duplex steels have...
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Influence of pitting corrosion on fatigue and corrosion fatigue of ship structures. Part I: pitting corrosion of ship structures.
PublikacjaThe paper is a literature survey focused on pitting corrosion and its influence on fatigue of ship and offshore steels. Mechanisms of short- and long-term pitting corrosion in marine environment have been described including pit nucleation and growth phases. Some models of pit growth versus time of exposure have been presented. Some factors which influence the pit growth have been discussed briefly.
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Influence of process of straightening ship hull structure made of 316L stainless steel on corrosion resistance and mechanical properties
PublikacjaThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries, for architectural elements, and many others. The chemical composition of corrosion-resistant...
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Determination of causes of accelerated local corrosion of austenitic steels in water supply systems
PublikacjaThis paper concerns an inspection of a water supply system, made of AISI 304 steel, which showed signs of local corrosion at the weld. Such corrosion caused material perforation after very short periods of operation. It was revealed that steel was sensitised during the welding process. It was also proven that chromium micro-segregation occurred in the alloy leading to galvanic cell formation which initialised the process of pitting...
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Te use of acoustic emission for assessment of the oil lubricity in a four-ball tester
Publikacjain view of the increased dynamic and temperature load in the compression-ignition engine tribological systems, particular attention is drawn to the problem of such lubrication of the friction nodes that after breaking the boundary layer it could be restored without any wear occurring. therefore, an idea has been devised of introducing to friction nodes, with the lubrication oils, of new substances (operational preparations) modifying...
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Aspects of intergranular corrosion of AISI 321 stainless steel in high-carbon-containing environments
PublikacjaPurpose – The purpose of this paper is to present a case study of unexpected sensitization to intergranular corrosion of highly resistant AISI 321 steel in petrochemical conditions, where it was subjected to the simultaneous influence of elevated temperature of 250°C and vapors from the asphalt production process. Design/methodology/approach – Corrosion coupons were exposed in an installation carrying asphalt vapors. To identify...
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Potential changes in an electric field and electrolytic corrosion.
PublikacjaSources have been described of corrosively hazardous electric fields and methods of determination of the corrosion hazard to metal structures caused by electrolytic corrosion. Results of potential and impedance investigations in the field of stray currents flowing out of a tram traction and in the presence of a defined electric field of low frequency have been presented. Uncertainties have been indicated relating to the generally...
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High temperature corrosion and corrosion protection of porous Ni22Cr alloys
PublikacjaIn this work corrosion kinetics of the porous IN625 alloy is studied in the temperature range of 700 °C – 800 °C in air and humidified hydrogen for up to 1000 hours. Moreover, an effective and simple method of reducing corrosion rates of porous alloys by the infiltration of the rare earths elements is shown. Modification by the yttrium containing precursor reduces the corrosion rate by a factor of 50 in air at 700 °C so that the...
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Effect of native air-formed oxidation on the corrosion behavior of AA7075 aluminum alloys
PublikacjaThe microstructure of aluminum alloys plays a key role in their corrosion resistance. In particular, the presence of intermetallic precipitates differing in the potential from the alloy matrix induces local corrosion. The study presents the effect of native air-formed oxidation on the corrosion behavior of AA 7075 aluminum alloy. Various microscopic and spectroscopic techniques were used to examine the changes occurring in the...
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Analysis and assessment of the acoustic emission suitability for determination of the energy states of a tribological system in the form of a four-ball tester friction node
PublikacjaThe present operating safety and cost reduction requirements of the compression ignition engines make it necessary to search for new methods of detecting their defects, e.g. by the analysis of acoustic emission signals coming from the slide bearings. The paper presents non-destructive measurements of acoustic emission (AE) in order to obtain information on the processes taking place in a tribological system under the continuously...
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Aqueous Molybdate Provides Effective Corrosion Inhibition of WE43 Magnesium Alloy in Sodium Chloride Solutions
PublikacjaCorrosion and corrosion inhibition of WE43 magnesium alloy were investigated in NaCl solutions containing different amounts of sodium molybdate. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the mechanism of corrosion inhibition by molybdates. Electrochemical data showed that Na2MoO4 inhibitor provides reliable inhibition at concentrations at and above 100 mM. Raman and XPS spectroscopy demonstrated...
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Sintered Duplex Stainless Steels Corrosion Properties
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Sintered Duplex Stainless Steels Corrosion Properties
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Hydrogen-enhanced stress corrosion cracking and corrosion fatigue of HSLA steels in sea-water
PublikacjaPrzedstawiono ocenę podatności stali o wysokiej wytrzymałości na naprężeniowe pękanie korozyjne i zmęczenie korozyjne wspomagane przez wodór. Wykonano próby powolnego rozciągania i zmęczenia niskoczęstotliwościowego na stalach 17HMBVA i 14HNMBCu oraz ich złączach spawanych, w środowisku wody morskiej, przy polaryzacji katodowej. Zamieszczono wyniki badań elektrochemicznych oraz przełomów na skaningowym mikroskopie elektronowym.
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Wet H2S corrosion and degradation of pipeline in amine regeneration system
PublikacjaThe paper presents the results of NDT examinations, metallographic tests and risk assessment of degradation related to corrosion of amine regeneration unit in a desulphurisation system. Intensive corrosion resulting from acid gases environment upon water condensation causes perforation of the pipeline. Detailed analysis reveals cracking related to the mechanism of wet H2S. Hydrogen penetration, resulting from the wet H2S process,...
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Microstructure and corrosion behaviour of carbon steel and ferritic and austenitic stainless steels in NaCl solutions and the effect of p-nitrophenyl phosphate disodium salt
PublikacjaThe microstructure and corrosion behavior of carbon steel (CSA516) and ferritic (SS410) and austenitic (SS304L) stainless steels were studied and compared. Corrosion tests were carried out in 0.5 M NaCl solutions. Rates of corrosion were monitored based on weight loss, Tafel extrapolation and linear polarization resistance (LPR) methods. Rates of corrosion were ranked following the order: CSA516 >> SS410 > SS304L. The impact of...
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The Impact of Crushed Rock Spoil on Pitting Corrosion of Selected Stainless Steel
PublikacjaThe paper presents the results of the pitting resistance investigations of selected stainless steels in the chloride environment and the simultaneous impact of erosive factors using the cyclic polarization technique. Additionally, using electrochemical techniques, ie: electrochemical impedance spectroscopy (EIS) and measurement of corrosion potential, the behavior of the passive layer of selected stainless steels in the environment...
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Corrosion hazards and inhibitor protection in the seawater injection system on the Baltic sea rig
PublikacjaOil extraction efficiency in LOTOS Petrobaltic Company is increased by means of injection of seawater into an oilfield aquifer, which is implemented on the Baltic Beta rig, operating on the Baltic Sea. Operational experience has shown a significant degree of corrosion aggressiveness in the injected water, which necessitates frequent repairs of the seawater injection installation. Evaluation of the corrosion phenomena is crucial...
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Multi-sensor monitoring of the corrosion rate and the assessment of the efficiency of a corrosion inhibitor in utility water installations
PublikacjaThis paper presents an implementation of the monitoring of the corrosion rate and the assessment of the efficiency of a corrosion inhibitor in a utility water installation using an automated corrosion monitoring system. Due to the fact that the corrosion inhibitor was added to water intended for human consumption, it was necessary to build a multi-sensor monitoring system. In order to implement corrosion monitoring using a linear...
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Surface and Corrosion Properties of AA6063-T5 Aluminium Alloy in Molybdate-containing Sodium Chloride Solutions
PublikacjaCorrosion properties of aluminium alloy AA6063-T5 were investigated in molybdate-containing NaCl solutions. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the mechanism of corrosion inhibition by molybdates. SEM-EDX, magnetic force, and intermodulation electrostatic force microscopy data suggested that the inhibition initiation preferentially occurred over Fe-rich cathodic IMPs. Spectroscopic...
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Corrosion fatigue crack propagation rate characteristics for weldable ship and offshore steels with regard to the influence of loading frequency and seawater temperature
PublikacjaAfter Vosikovsky (1975), the corrosion fatigue crack growth rate (CFCGR) characteristics have been divided into three regions. The region-III rates are very close to mechanical fatigue crack growth rates. CFCGR formulae, including the long-crack length effect (in region I only), the loading frequency effect (in region II only), and the saltwater temperature effect, have been proposed. It has been assumed that CFCGR is proportional...
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The Application of Dynamic Electrochemical Impedance Spectroscopy (DEIS) Technique in Corrosion and Corrosion Inhibition Studies
Publikacjaorrosion studies have attracted considerable interest in the areas of materials chemistry and industrial chemistry, as it affects the direct and indirect costs of industry, leading to huge economic setbacks due to the need for repair, maintenance, and even shutdowns due corrosion damage. This new volume is a comprehensive resource that presents new and up-to-date, theoretical, and experimental corrosion inhibition studies.
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DETERMINATION OF THE EFFECT OF ENVIRONMENTAL FACTORS ON THE CORROSION OF WATER DISTRIBUTION SYSTEM BASED ON ANALYSIS OF ON-LINE CORROSION MONITORING RESULTS
PublikacjaCorrosion of water distribution system is a significant issue causing problems with quality, safety and continuity of distribution. The changes of corrosion rates of the water distribution systems in Cracow made of carbon steel were investigated by analysis of online corrosion monitoring system results. Corrosion rates were determined using the linear polarization method. The impact of rain, temperatures, conductivity, dissolved...
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Corrosion behavior of vacuum sintered duplex stainless steels
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The corrosion resistance of laser surface alloyed stainless steels
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Effect of the Post-Weld Surface Condition on the Corrosion Resistance of Austenitic Stainless Steel AISI 304
PublikacjaSurfaces of welded elements made of corrosion-resistant (stainless) steels develop temper colours. The removal of thickened oxide layers off steels exposed to temperatures below 300°C is necessary and entails the restoring of high corrosion resistance of the stainless steel. The article presents tests concerned with the effect of a method applied to remove post-weld temper on the corrosion resistance of austenitic stainless steel...
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Development Of Dynamic Method For Evaluation Of Corrosion Rate On The Example Of Organic Corrosion İnhibitor
PublikacjaMeasurements of the corrosion rate belong to the most important aspects of materials science. In order to reduce material loss corrosion inhibitors are used. However selection of proper inhibitor should be based on evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character so physicochemical parameters are changing in time. Most of actually used methods...
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High-temperature Corrosion of ~ 30 Pct Porous FeCr Stainless Steels in Air: Long-Term Evaluation Up to Breakaway
PublikacjaIn this work, a long-term (up to 6000 hours) corrosion evaluation of three porous (~ 30 pct of initial porosity) ferritic iron-chromium alloys with different Cr contents (20, 22, and 27 wt pct of Cr) was carried out at 600 C, 700 C, 800 C, and 900 C in air. Mass gain measurements and SEM analyses revealed that at temperatures above 600 C, all alloys exhibit breakaway corrosion, whereas at 600 C, none of the alloys were heavily...
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Experimental and numerical identification of corrosion degradation of ageing structural components
PublikacjaThe study presents experimental and numerical identification of corrosion degradation of thin-walled structural components employing guided wave propagation. The steel structural components are subjected to through-thickness varying corrosion degradation levels. The developed approach using the non-destructive guided wave-propagation quantifies the equivalent average corrosion degradation level by exploring a limited number of...
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Influence of pitting corrosion on fatigue and corrosion fatigue of ship and offshore structures. Part II: Load - pit crack interaction
PublikacjaIn the paper has been discussed influence of stresses on general corrosion rate and corrosion pit nucleation and growth rate, whose presence has been questioned by some authors but accepted by most of them. Influence of pit walls roughness on fatigue life of a plate suffering pit corrosion and presence of so called "non damaging" pits which never lead to initiation of fatigue crack, has been presented. Possibility of prediction...
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Corrosion monitoring by harmonic analysis in aqueous environments
PublikacjaThis paper presents tests concerning the rate of corrosion in non-alloy steel (type S235JR) in an aqueous environment, with an additive of sodium chloride by means of polarization resistance measurements and harmonic analysis. The tests have been carried out for steel samples exposed to the testing environment for six weeks, in order to obtain a constant rate of corrosion in the function of time. The measurements have aimed at...
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Corrosion resistance of dissimilar austenite and duplex steels welded joints
PublikacjaW artykule przedstawiono wpływ warunków spawania, a zwłaszcza energii liniowej, na odporność korozyjną złączy różnoimiennych stali austenitycznej 316L i typu duplex 2203. Przedstawiono wyniki testów korozyjnych:korozji wżerowej wg ASTM G48 oraz korozji naprężeniowej badanej w próbach odkształcania z małą pędkością w środowisku roztworu chlorku magnezowego.