rss_2.0KOM – Corrosion and Material Protection Journal FeedSciendo RSS Feed for KOM – Corrosion and Material Protection Journal – Corrosion and Material Protection Journal 's Cover on silver based coatings<abstract> <title style='display:none'>Abstract</title> <p>New trends in the automotive and construction industries are leading manufacturers to develop new materials with added value. In this article, we deal with the introduction of such a material, namely a silver-based emission coating, which is used in both architecture and the automotive industry. Silver-based coating thus makes it possible to increase the driver’s comfort, or to increase the comfort of working in the office on hot steamy days. This coating changes the transmittance of IR radiation from or to the building, or from or to the car. The coating is based primarily on the presence of layers of silver, which are able to provide the primary functions of modulation of incoming and outgoing radiation. Silver-based coatings can also be used to heat, for example, car windshields. The production of a silver-based coating is very demanding and sensitive to the formation of coating defects. In this article, we discuss common coating defects and discuss their possible origins.</p> </abstract>ARTICLE2022-07-07T00:00:00.000+00:00Experimental assessment of packaging paper properties effect in combination with storage conditions on the adhesion performance of automotive glass<abstract> <title style='display:none'>Abstract</title> <p>The aim of this work was an experimental comparison of different types of packaging paper, determining the effect of packaging material properties in combination with storage conditions on the purity of glass surface and the related quality of adhesion of bonded materials. In the automotive industry, the quality of adhesion is a key factor, as automotive glass must meet the safety requirements. During the experiments, the glass sheets were wrapped in four types of paper and stored according to the conditions that are common in a real production. The research was focused on the influence of different composition of packaging papers on the resulting adhesive properties of glass sheets. According to the results obtained in this work, it can be stated that during the storage there is an interaction between paper and glass. According to XRF analyzes, ongoing corrosion of the glass can be inferred. The resulting adhesion was assessed based on a peel test, which took place under defined conditions given by standard customer specifications. It has been observed that the negative effect of unsuitable paper increases over time. For optimal adhesion it is necessary to emphasize the packaging materials and the storage conditions of the glass. The results and knowledge achieved in this work can significantly improve the quality of production in which a material is glued to the glass surface.</p> </abstract>ARTICLE2022-07-07T00:00:00.000+00:00Metal Antik conservation coatings on iron specimens<abstract> <title style='display:none'>Abstract</title> <p>The surface treatment of historical iron artefacts involves application of right conservation coating to the material to prevent further corrosion deterioration. Among common conservation agent of iron belong tannate coating, which is considerably preferred with the desired black appearance of the surface. In this work the new potentional conservation agent Metal Antik was studied. The change of this possible surface treatment was evaluated over time. The comparison between long-term exposed samples (15 years), short-term exposed samples (1.5 year) and fresh cured samples was done by spectrocolorimetry measurement. This was also compared to standard samples prepared with tannate coating. Surface analysis for all types of samples was done by μ-Raman spectroscopy. Results proved that effect of time changes the surface of coatings. It was demonstrated by colour change of surface and by formation of areas with local corrosion. Another study of Metal Antik in order to improve corrosion resistance is open.</p> </abstract>ARTICLE2022-07-07T00:00:00.000+00:00Corrosion and tribological behaviour of Friction Stir Processed AA2024-T351 alloy<abstract> <title style='display:none'>Abstract</title> <p>AA2024-T351, a heat treatable aluminum alloy, has a high strength to weight ratio and good fracture resistance and has application mainly in the aircraft and aerospace sector. However, the alloy is susceptible to high corrosion because of the secondary phases (Al<sub>2</sub>Cu) present in the matrix. With an objective to increase the corrosion and wear resistance, Friction Stir Processing is applied to engineer the morphology and dispersion of the Al<sub>2</sub>Cu phase in the alloy. The friction stir processing trials are performed by varying the tool rotation speed, tool traverse speed, and shoulder diameter, as the properties of the friction stir processed region depend on the proper selection of process parameters. A hybrid linear-radial basis function model is developed to explore the effect of tool rotation speed, tool traverse speed, and shoulder diameter on the grain size, microhardness, corrosion rate, wear rate, and corrosion potential of the friction stir processed AA2024-T351 alloy. The predominant corrosion mechanism and wear regimes in AA2024-T351 alloy are understood from the characterization study on the surface morphology and elemental analysis of the corroded and worn specimens. The optimum friction stir processing parameters that improve the grain refinement, microhardness, corrosion resistance and wear resistance of AA2024-T351 alloy are established.</p> </abstract>ARTICLE2022-07-07T00:00:00.000+00:00Resistance of the welded joint of austenitic steel NEUTRONIT A 976 SM in the corrosive environment of boric acid<abstract> <title style='display:none'>Abstract</title> <p>The paper deals with the influence of the operating environment on the safe resistance of the welded joint of the construction material used in the nuclear power industry in the production of spent nuclear fuel containers. This material contains a higher percentage of alloying boron and is used as a shielding construction material for neutron and gamma radiation. It is used to produce baskets for spent nuclear fuel containers. When the containers are being filled, the welded joint of the basket structure are briefly exposed to an aqueous boric acid solution. The aim of this work was to determine the effects of exposure to the corrosive boric acid environment on the mechanical properties of the material. Tensile tests on the original weld and post weld exposure in H<sub>3</sub>BO<sub>3</sub> and corrosion cracking tests on unexposed welds were performed. The evaluation of the results revealed that the exposure to the corrosive environment of boric acid did not significantly affect the strength characteristics of the tested material NEUTRONIT A 976 SM.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Dissimilar weld joint corrosion in simulated boiler water environment<abstract> <title style='display:none'>Abstract</title> <p>This paper is focused on the problematics of weld joint corrosive degradation in the boiler water environment. The boiler water is commonly used in power industry. The corrosion experiment simulated the boiler water environment during shutdown, when chemicals may be concentrated in the deposits, or as a result of evaporation. The corrosion experiment was performed on heterogeneous weldments made of P265GH//X6CrNiTi18-9 steels in the environment of stagnant boiler water with the addition of NaCl for 53 days. The data showed only minimal weight losses, and small changes in the measured fracture toughness of the welded joint. At the same time, a tendency for a mechanical weakening of the welded joint with the increasing aggressivity of the boiler water environment was observed. The metallographic analysis was performed to describe the nature of corrosive degradation.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Prediction models for the kinetics of iron boride layers on AISI 316L steel<abstract> <title style='display:none'>Abstract</title> <p>The boronizing kinetics of AISI 316L steel has been analyzed by employing five prediction models. The boron diffusion coefficients as well as the growth rate constants in the FeB and Fe<sub>2</sub>B phases were firstly evaluated in the range of 1123-1223 K. Afterwards, the values of boron activation energies in FeB and Fe<sub>2</sub>B were secondly deduced by adopting the Arrhenius relationships.In addition, the prediction models have been validated experimentally for two boronizing conditions (1170 K for 1.6 h and 1210 K for 1.1 h). The predicted results were deemed very concordant with the experiments. Furthermore, advantages and limitations about the applicability of these models were also discussed.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Innovative accident tolerant nuclear fuel materials will help extending the life of light water reactors<abstract> <title style='display:none'>Abstract</title> <p>Nuclear power is a significant source of clean energy that can be used to mitigate climate change. In the western world, the average life of light-water power-reactors is increasing because no new reactors are being connected to the grid. In order to extend the life of the existing reactors innovative materials are being considered for the fuel of the reactors. The newer materials would be more resistant to a loss of coolant accident and allow for longer times between refueling plus permitting overall extended burn-ups, which will make the reactors safer and more economical to operate. This never used before in reactor materials include cladding concepts such as: 1) coated zirconium alloys, 2) monolithic iron-chromium-aluminum alloys, and 3) silicon carbide composites.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Growth kinetics of diiron boride (FeB) layer on a carbon steel by four approaches<abstract> <title style='display:none'>Abstract</title> <p>The pack-boriding kinetics of SAE 1020 steel has been addressed through utilizing four mathematical approaches in case of the formation of diiron boride layers. The values of boron diffusivities and activation energies in Fe<sub>2</sub>B were assessed in the interval of 1123 to 1223 K by using four models. Finally, the four models were experimentally verified by comparing the predicted results to the experimental value of Fe<sub>2</sub>B layer thickness determined at 1198 K for 6 hours. Finally, the simulated layers’ thicknesses agreed with the experimental result. In addition, similarities and differences observed in the models were also discussed.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Impact of the diffusion coefficient calculation on predicting FeB boride layer thickness<abstract> <title style='display:none'>Abstract</title> <p>In this study, a single-phase boride layer thickness Fe<sub>2</sub>B is predicted on two different substrates (Armco iron and XC38 steel) by following the integral method. This method is a mathematical model based on a system of differential algebraic equations that help to deduce the diffusion coefficient, which is the key factor on predicting the layer thickness. Literatures cover different diffusion coefficients for each substrate, albeit researchers usually extract from experimental data, variations of growth rate constants within only one time treatment and deduce the diffusion coefficient from them. This deduction is done via an estimation of a frequency factor and an activation energy from the growth rate constants. Therefore, our main aim is to illustrate the impact of the deduction of the diffusion coefficient on predicting the boride layer thickness. Lastly, the impact with and without incubation time on the boriding kinetics of both substrates was also examined.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Experimental studies on the corrosion inhibition of mild steel by 1-(phenylamino-1,3,4-thiadiazol-5-yl)-3-phenyl-3-oxopropan complemented with DFT Modeling<abstract> <title style='display:none'>Abstract</title> <p>1-(Phenylamino-1,3,4-thiadiazol-5-yl)-3-phenyl-3-oxopropan (PTPO) was selected as the investigated material for studying the protection performance for mild steel in 1 mol L-1 hydrochloric acid solution. The inhibitor was assessed using weight loss measurements complemented with morphological analytical techniques and density functional theory (DFT) modelling. The PTPO demonstrated significant inhibitive efficacy of 95.4% in the presence of 500 ppm at 303 K. The protection efficiency increases with the concentration increasing from 100 to 500 ppm, and no significant effect after 500 ppm. Furthermore, gravimetric findings reveal that the protection efficiency at 500 ppm PTPO increases with immersion period and increasing temperature (303-333 K), due to the effective adsorption of PTPO on the mild steel surface, and the protection efficiency value is 95.8% at 48 h of exposure and 95.4%, 95.4%, 95.7% and 95.9% at 303, 313, 323 and 333 K, respectively. The adsorption of PTPO on the mild steel surface obeyed the Langmuir adsorption isotherm model and revealing the mode of chemisorption adsorption. According to the DFT calculations, protection by PTPO is essentially performed by the heteroatoms in the inhibitor molecules which represented the adsorption sites, and the aromatic rings increase the electrostatic interaction between the PTPO molecules and the mild steel surface. The surface morphological studies, weight loss measurements, and DFT computational studies are in good agreement and that the selected corrosion inhibitor is adsorbed on the mild steel surface to form a protected layer on the surface of mild steel against the hydrochloric acid solution.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Corrosion assessment of a bronze equestrian statue exposed to urban environment<abstract> <title style='display:none'>Abstract</title> <p>This paper presents the characterization of the conservation state of a bronze equestrian statue exposed outdoor, through an in-situ, multi-analytical, and non-invasive approach. The artefact under study is a bronze equestrian statue, devoted to Alfonso La Marmora, placed in an urban environment in the city of Turin. The investigation was carried out in the framework of a restoration intervention, with the principal aim of characterizing the overall conservation state of the sculpture to provide the conservators with information useful to develop a tailored restoration plan. X-ray fluorescence spectroscopy (XRF) was carried out for the identification of the elements present in the artefact alloy, showing that the statue was made using mainly two bronze alloys. Electrochemical Impedance Spectroscopy (EIS) was performed to study the corrosion mechanisms and to define the protective effectiveness of the patina present on the surfaces. Eventually, Raman spectroscopy (RS) was performed to characterize the chemistry and microstructure of the corrosion products, mainly identified as sulphates. The combination of these techniques allowed to confirm the presence of wax layers from previous restoration work, still capable to protect the metal substrate against corrosion. In addition, it was possible to correlate the conservation state to the exposure conditions and location on the statue.</p> </abstract>ARTICLE2022-04-18T00:00:00.000+00:00Protective ability of lead corrosion products in indoor atmosphere with acetic acid vapours<abstract> <title style='display:none'>Abstract</title> <p>Lead corrosion products can undergo certain changes over the time in terms of composition. How these changes affect the corrosion of the underlying lead is an important question for protection of historical lead artefacts. In this work, we focus on characterization of changes in composition of lead corrosion products and how the composition affects corrosion of the lead substrate. Prepared model corrosion products on lead coupons were exposed to air at different relative humidity and concertation of acetic acid vapours. Composition of the corrosion products was analysed by XRD and corrosion rate was calculated from gravimetric data. Measurement of polarization resistance was implemented to get more insight into the protective ability of formate corrosion products. With lead formate covering the surface, the corrosion rate of lead coupons was minimal even in humid air with 400 ppb of acetic acid vapours. Acetic acid was however able to alter lead carbonate corrosion products resulting in increased corrosion rate.</p> </abstract>ARTICLE2021-12-30T00:00:00.000+00:00Indoor corrosivity classification based on lead coupons<abstract> <title style='display:none'>Abstract</title> <p>Air pollution in museums, libraries, churches, and other indoor environments of cultural heritage objects was studied since 1980s. For classification of corrosivity for such type of indoor environments the ISO 11844 series was developed in 2006. In 2020 the revision of this ISO 11844 series had been finished, where lead was included as standard specimen with high sensitivity to vapour organic acids. This paper gives results of exposure of lead standard coupons in museums and other similar indoor environments together with measurement of climatic parameters and air pollution to verify the new approach.</p> </abstract>ARTICLE2021-12-30T00:00:00.000+00:00Inspection possibilities of metallic material surface integrity by conventional ultrasonic technique<abstract xml:lang="en"><title style='display:none'>Abstract</title><p> The article is focused on the possibilities of ultrasound surfaces control on metallic materials by conventional ultrasonic techniques. Physical principles, types of ultrasonic waves to be used for surface control are described in the theoretical part. Three surface control techniques are listed in the experimental part of article. The first technique is a common control by angle ultrasonic probe with using transverse waves. The second technique is surface control by 30-70-70 creep waves and third techniques is surface testing by Rayleigh waves. Practical examples of ultrasonic testing for all techniques are illustrated. The conclusion of the article is devoted to the advantages and limitations of the individual testing methods.</p></abstract>ARTICLE2017-07-22T00:00:00.000+00:00The influence of deformation on the corrosion properties of the material<abstract xml:lang="en"><title style='display:none'>Abstract</title><p> This work was focused on changes of corrosion behaviour influence of deformation. The This work focuses on changes in corrosion behaviour under the influence of deformation. The main purpose is to observe the changes caused by tensile stress. The experimental material used is steel 1.4301 and titanium GRADE 2. The measurements were carried out using a potentiostat, which measures potential changes over time and electric current. The electrolyte used was 3.5% NaCl. Corrosion properties, especially polarization resistance, corrosion potential and corrosion rate, were evaluated from the measurements. The results demonstrate the changing corrosion properties depending on deformation. The corrosion properties worsened as the deformation increased.</p></abstract>ARTICLE2017-07-22T00:00:00.000+00:00Copper and copper patina<abstract xml:lang="en"><title style='display:none'>Abstract</title><p> This article is aimed at summarizing knowledge about copper and patina that is formed on the surface of copper. The article describes chemical processes in patina formation and explains the difference between natural and artificial patina, as well as some methods used in the investigation of patina such as XRD analysis, EIS analysis, Raman spectroscopy</p></abstract>ARTICLE2017-07-22T00:00:00.000+00:00The tribological properties of Al-brasses in various environments<abstract xml:lang="en"><title style='display:none'>Abstract</title><p> Tribological properties of Al-brass pipes of various producers were studied in different environments. The tested brasses have very similar chemical composition, but they differ in microstructure due to mainly by heat treatment after cold drawing. Microstructure as well as roughness of surface influence chemical and mechanical properties which are important in operating conditions. The experiments of tribological behavior were made in various environments, dry air, cooling treated water and 3.5 % solution of NaCl at room temperature 21 ± 2°C. The tribological tests were carried out on the Linear Tribometer at normal loading 5 N by the method ball on plate for the duration of 5500 s. The measured friction coefficients were evaluated by the program DIAdem and the diagrams were created from signal generated by software NSignal Express</p></abstract>ARTICLE2017-07-22T00:00:00.000+00:00Corrosion problems and solutions in oil, gas, refining and petrochemical industry<abstract xml:lang="en"><title style='display:none'>Abstract</title><p> The aim of this work is to describe and analyze corrosion problems and their solutions in oil, gas, and refining industry. Corrosion phenomena and factors influencing them are discussed. Corrosion control and monitoring methods are illustrated. Corrosion management plays vital role in the solving of corrosion problems. The results are summarized in new book of the author “Corrosion Problems and Solutions in Oil Refining and Petrochemical Industry” published by Springer in 2016.</p></abstract>ARTICLE2017-07-22T00:00:00.000+00:00Anchorage length of patented wire cables in prestressed bridge girders<abstract> <title style='display:none'>Abstract</title> <p>This paper briefly describes the methodology, performance and the obtained results of unique experiments performed on original I-73 precast bridge girders. The main objective of the experiments was to determine the actual anchorage length of corroded-through fully grouted prestressing reinforcement (prestressing wires), which is important for determination of the residual load-bearing capacity of prestressed structures. Observation probes leading all the way to the prestressing wires were drilled on selected sections of the girders along the length of the prestressing reinforcement. Optical image acquisition devices were then installed at these probes. Subsequently, controlled breakage of the patented wires (corrosion failure simulation) and observation of the changes that occurred in the prestressing wires after relief of stress were carried out. Evaluation of the experiments was then performed by analyzing the images obtained before and after the prestressing reinforcement failure.</p> </abstract>ARTICLE2021-12-30T00:00:00.000+00:00en-us-1