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Article
Publication date: 15 February 2022

Zhenhuan Gao, Yongxuan Liu, Chong Wang, Huisheng Yang, Lining Xu and Lijie Qiao

This study aims to report the CO2 corrosion performance of 3Cr steel and 3Cr2Al steel and reveal the role of aluminum in mitigating corrosion of low-Cr steel.

Abstract

Purpose

This study aims to report the CO2 corrosion performance of 3Cr steel and 3Cr2Al steel and reveal the role of aluminum in mitigating corrosion of low-Cr steel.

Design/methodology/approach

Aluminum was added to 3Cr steel to prepare a new type of 3Cr2Al steel, and the effect of aluminum on the corrosion resistance of pipeline steel was studied using morphology observation and composition analysis, weight loss tests and electrochemical test.

Findings

In the CO2/O2 coexistence environment, the average corrosion rate of the 3Cr2Al steel was obviously lower than that of the 3Cr steel. The addition of aluminum expanded the range of prepassivation, and the dynamic potential polarization curve of 3Cr2Al steel showed duplex prepassivation phenomena. 3Cr steel underwent severe local corrosion, and 3Cr2Al steel underwent uniform corrosion. The addition of aluminum contributed to the formation of a dense corrosion product layer and greatly reduced the localized corrosion sensitivity.

Originality/value

The studies on CO2 corrosion of aluminum containing low-Cr steel are quite rare. This study clarifies the role of aluminum by comparing the corrosion behavior of 3Cr2Al and 3Cr steel. The effect of aluminum on the growth of corrosion product film was discussed, and the duplex prepassivation phenomena of Cr and Al were revealed.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 18 July 2022

Thac Quang Nguyen, Xuan Tung Nguyen, Tri N. M. Nguyen, Thanh Bui-Tien and Jong Sup Park

The strength and stiffness of steel deteriorate rapidly at elevated temperatures. Thus, the characteristics of steel structures exposed to fire have been concerned in…

Abstract

Purpose

The strength and stiffness of steel deteriorate rapidly at elevated temperatures. Thus, the characteristics of steel structures exposed to fire have been concerned in recent years. Most studies on the fire response of steel structures were conducted at uniformly distributed temperatures. This study aims to evaluate the buckling capacity of steel H-beams subjected to different loading conditions under non-uniform heating.

Design/methodology/approach

A numerical investigation was conducted employing finite element analysis software, ABAQUS. A comparison between the numerical analysis results and the experimental data from previous studies was conducted to verify the beam model. Simply supported beams were loaded with several loading conditions including one end moment, end equal moments, uniformly distributed load and concentrated load at midspan. The effects of initial imperfections were considered. The buckling capacities of steel beams under fire using the existing fire design code and the previous study were also generated and compared.

Findings

The results showed that the length-to-height ratio and loading conditions have a great effect on the buckling resistance of steel beams under fire. The capacity of steel beams under non-uniform temperature distribution using the existing fire design code and the previous study can give unconservative values or too conservative values depending on loading conditions. The maximum differences of unconservative and conservative values are −44.5 and 129.2% for beams subjected to end equal moments and one end moment, respectively.

Originality/value

This study provides the buckling characteristics of steel beams under non-uniform temperature considering the influences of initial imperfections, length-to-height ratios, and loading conditions. This study will be beneficial for structural engineers in properly evaluating structures under non-uniform heating conditions.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 11 July 2022

Xiaomin Zhao, Fuminobu Ozaki, Takeo Hirashima, Kei Kimura, Yukio Murakami, Jun-ichi Suzuki and Naoya Yotsumoto

The main purpose of this study was to propose theoretical calculation models to evaluate the theoretical bending strengths of welded wide-flange section steel beams with…

Abstract

Purpose

The main purpose of this study was to propose theoretical calculation models to evaluate the theoretical bending strengths of welded wide-flange section steel beams with local buckling at elevated temperatures.

Design/methodology/approach

Steady-state tests using various test parameters, including width-thickness ratios (Class 2–4) and specimen temperatures (ambient temperature, 400, 500, 600, 700, and 800°C), were performed on 18 steel beam specimens using roller supports to examine the maximum bending moment and bending strength after local buckling. A detailed calculation model (DCM) based on the equilibrium of the axial force in the cross-section and a simple calculation model (SCM) for a practical fire-resistant design were proposed. The validity of the calculation models was verified using the bending test results.

Findings

The strain concentration at the local buckling cross-section was mitigated in the elevated-temperature region, resulting in a small bending moment degradation after local buckling. The theoretical bending strengths after local buckling, evaluated from the calculation models, were in good agreement with the test results at elevated temperatures.

Originality/value

The effect of local buckling on the bending behaviour after the maximum bending strength in high-temperature regions was quantified. Two types of calculation models were proposed to evaluate the theoretical bending strength after local buckling.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 19 July 2022

G. Jaya Kumar, Tattukolla Kiran, N. Anand and Khalifa Al-Jabri

Most of the industrial buildings which are designed to moderate loads are constructed using light gauge cold-formed steel (CFS) sections. Residual mechanical properties of…

Abstract

Purpose

Most of the industrial buildings which are designed to moderate loads are constructed using light gauge cold-formed steel (CFS) sections. Residual mechanical properties of CFS sections exposed to elevated temperature need to be investigated as it is necessary to predict the deterioration of elements to avoid failure of the structure or its elements. Also, it would be helpful to decide whether the structural elements need to be replaced or reused. The use of fire-resistant coatings in steel structures significantly reduces the cost of repairing structural elements and also the probability of collapse. This study investigates the effect of fire-resistant coating on post-fire residual mechanical properties of E350 steel grade.

Design/methodology/approach

In this study, an attempt has been made to evaluate the residual mechanical properties of E350 steel. A tensile coupon test was performed for the extracted specimens from the exposed CFS section to determine the mechanical properties. Four different fire-resistant coatings were selected and the sections were coated and heated as per ISO 834 fire temperature curve in the transient state for time durations of 30 minutes (821°C), 60 minutes (925°C), 90 minutes (986°C), and 120 minutes (1,029°C). After the exposure, all the coupon specimens were cooled by either ambient conditions (natural air) or water spraying before conducting the tension test on these specimens.

Findings

At 30 min exposure, the reduction in yield and ultimate strength of heated specimens was about 20 and 25% for air and water-cooled specimens compared with reference specimens. Specimens coated with vermiculite and perlite exhibited higher residual mechanical property up to 60 minutes than other coated specimens for both cooling conditions. Generally, water-cooled specimens had shown higher strength loss than air-cooled specimens. Specimens coated with vermiculite and perlite showed an excellent performance than other specimens coated with zinc and gypsum for all heating durations.

Originality/value

As CFS structures are widely used in construction practices, it is crucial to study the mechanical properties of CFS under post-fire conditions. This investigation provides detailed information about the physical and mechanical characteristics of E350 steel coated with different types of fire protection materials after exposure to elevated temperatures. An attempt has been made to improve the residual properties of CFS using the appropriate coatings. The outcome of the present study may enable the practicing engineers to select the appropriate coating for protecting and enhancing the service life of CFS structures under extreme fire conditions.

Details

Journal of Structural Fire Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 13 April 2015

Spyros Papaefthymiou, Constantinos Goulas and Vasiliki Panteleakou

Identification of the critical process conditions that enhance Cu diffusion in ferrite grain boundaries and promote precipitation of Cu-rich particles in the proximity of…

154

Abstract

Purpose

Identification of the critical process conditions that enhance Cu diffusion in ferrite grain boundaries and promote precipitation of Cu-rich particles in the proximity of steel semi-finished products surface is crucial for every steel maker as it leads to the creation of hot shortness cracks in final products deteriorating surface condition. The purpose of this paper is to reveal the possible effect of Cu segregation in the metal/oxide interface, its role in surface crack initiation and, finally, to propose actions to prevent from hot shortness issues throughout the production chain of steel products.

Design/methodology/approach

The here presented study was based on S355 steel plate production starting from re-melting of scrap in an EAF, followed by metallurgical treatment in a Ladle Furnace, continuous casting, re-heating (RH) and thermo-mechanical rolling in a reversing mill. For the purposes of this study, more than ten heats, 100 t of steel each, were analyzed. Here presented are depicted steels in the high and low end of the permitted Cu-wt-% spectrum, 0.4 wt-% Cu (0.15 wt-% C, 1.1 wt-% Mn, VTi micro-alloyed steel) and 0.25 wt-% Cu (0.09 wt-% C, 1.2 wt-% Mn, NbTi micro alloyed steel), respectively.

Findings

Although Cu levels of 0.25-0.40 wt-% are well below the Cu solubility in austenite and ferrite (8 percent wt-% and 3 wt-% Cu, respectively) and within specifications, precipitation of Cu-rich particles is observed in industrial semi-finished and/or final products. Cu-rich precipitates and Cu segregation along grain boundaries near the steel surface lead to hot shortness cracks in industrial products.

Research limitations/implications

Hot shortness surface defects related to Cu presence in steel having significantly lower Cu amounts than its maximum solubility in austenite and ferrite does not make sense in first place. Correctly, Cu is expected to remain in solid solution. Identification of Cu-rich particles is explained on the basis of the development of double diffusion actions: interstitial diffusion of carbon (decarburization) and substitution diffusion of copper. Root cause analysis and reliable countermeasures will save financial and material resources during steel production.

Originality/value

Automobile scrap re-melting results in noticeable Cu amounts in EAF produced steel. Presence of Cu-rich particles in grain boundaries near the surface of intermediate or final products deteriorates surface quality through relevant surface defects. Identification of Cu-rich particles is explained on the basis of the development of double diffusion actions: interstitial diffusion of carbon and substitution diffusion of copper. Pre condition for metallic Cu precipitation in ferrite is the Cu amount to be above 3 wt-%, which is ten times higher than the usual permitted Cu amount in such steel grades. This pre-condition is met through austenite oxidation during RH.

Details

International Journal of Structural Integrity, vol. 6 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 23 May 2008

Frederico Guilherme Dantas dos Santos, Carlos Roberto Araújo and Vanessa de Freitas Cunha Lins

The purpose of this paper is to study the corrosion of the coupling of two different types of stainless steel, austenitic and ferritic, used in the fabrication of water…

1393

Abstract

Purpose

The purpose of this paper is to study the corrosion of the coupling of two different types of stainless steel, austenitic and ferritic, used in the fabrication of water reservoirs in the solar energy industry.

Design/methodology/approach

Potentiodynamic polarization and gravimetric immersion tests were used to evaluate corrosion of the coupling of two different types of stainless steel, austenitic and ferritic.

Findings

The galvanic corrosion was not significant in the case of the coupling of AISI 304 and 444 steels. The difference of the open circuit potentials obtained for the AISI 304 and AISI 444 steels was 28 mV for the polished samples. The galvanic current density (ig) was 55 nA/cm2. The corrosion observed in the stainless steel couple was in the weld area.

Research limitations/implications

The methodology used is adequate to evaluate generalized galvanic corrosion. The problem of the corrosion in the coupling of the stainless steels is a problem of localized corrosion and the observed 28 mV potential difference was lower than the dispersion of results usually obtained from readings of corrosion potentials in electrochemical cells.

Practical implications

The use of two different types of steel in contact with each other may lead to galvanic corrosion, and the welding of steel pieces may lead to several corrosion problems. Since the boiler may be used in different countries, subject to a great diversity of water quality, corrosion may be a significant problem.

Originality/value

Literature data of the AISI 444 steel corrosion behaviour are still scarce. The coupling of two different stainless steels (AISI 304 and 444) in the water reservoir manufacturing was a necessary requirement of the solar energy industry. The manufacturers of boilers must evaluate and quantify the corrosion processes, which occur in the equipment used in the solar energy industry. As the solar energy industry has matured in the last ten years, the corrosion of this equipment may be a significant problem in due course.

Details

Anti-Corrosion Methods and Materials, vol. 55 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 June 1997

Keith Charles Bendall

States that duplex (austenitic/ferritic) stainless steels offer properties of interest and a cost‐effective material selection solution for plant and equipment in the pulp…

1259

Abstract

States that duplex (austenitic/ferritic) stainless steels offer properties of interest and a cost‐effective material selection solution for plant and equipment in the pulp and paper industry. Reviews characteristics of duplex steels leading to successful long‐term applications of 22 Cr duplex and a copper containing 25 Cr super duplex stainless steel. Concludes that, applied correctly, two‐phase stainless steels can provide long‐term reliable maintenance‐free service in many pulp and paper plant environments.

Details

Anti-Corrosion Methods and Materials, vol. 44 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 July 2012

Jill M. Gradwell, Jonathan Amidon, Danielle LaJudice and Mary Westlake-Douds

This lesson uses Steel Town to explore the making of steel and life in a steel mill town during the Great Depression. Moving through four centers, students explore…

Abstract

This lesson uses Steel Town to explore the making of steel and life in a steel mill town during the Great Depression. Moving through four centers, students explore resources such as photographs, first-hand accounts, recipes, and songs from the era to learn what life was like at a steel mill, in a steelworker’s home and neighborhood, and throughout the town. Based on their analyses of the resources provided, students compare the benefits and drawbacks of technology to answer the ultimate question regarding steel production: “Is it worth it?” This lesson was created for use in a second or third grade classroom but can be adjusted for older students with the extensions provided.

Details

Social Studies Research and Practice, vol. 7 no. 2
Type: Research Article
ISSN: 1933-5415

Article
Publication date: 1 January 2006

Egnalda Pereira da Silva, Evandro de Azevedo Alvarenga, Maria das Mercês Reis de Castro and Vanessa de Freitas Cunha Lins

The purpose of this study was to select an atmospheric corrosion evaluation methodology and to establish a range of relative corrosion penetration and/or progress values…

Abstract

Purpose

The purpose of this study was to select an atmospheric corrosion evaluation methodology and to establish a range of relative corrosion penetration and/or progress values, which could be used as reference in the selection of materials for the civil construction industry.

Design/methodology/approach

Salt spray, field tests, accelerated cyclic tests and accelerated field tests were used to evaluate atmospheric corrosion resistance of civil construction materials. The cyclic accelerated test and the field test with saline solution spray were found to be appropriate for atmospheric corrosion resistance evaluation.

Findings

The corrosion resistance of aluminium killed mild steel, aluminium killed copper added steel, and electrogalvanized steels, all phosphatized and painted, were evaluated by field and accelerated corrosion tests. Of the materials studied, aluminium killed mild steel showed the least resistance to atmospheric corrosion. The use of aluminium killed copper added steel is recommended for material specification in the civil construction industry.

Research limitations/implications

Salt sprays are not adequate to evaluate atmospheric corrosion resistance. There are other cyclic tests that could be tested in future work.

Practical implications

Brazilian technical standards, which specify the metallic materials used in the civil construction industry, will be changed in order to include the construction steel corrosion resistance evaluation methodology, which is proposed in this paper. As a result, the tendency of the construction materials lifetime is set to increase.

Originality/value

This paper contributes to the improvement of the Brazilian Technical Standard by the inclusion of an atmospheric corrosion resistance requirement.

Details

Anti-Corrosion Methods and Materials, vol. 53 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 October 2003

H.Y. Leung and R.V. Balendran

Use of fibre‐reinforced polymer (FRP) composite rods, in lieu of steel rebars, as the main flexural reinforcements in reinforced concrete (RC) beams have recently been…

2517

Abstract

Use of fibre‐reinforced polymer (FRP) composite rods, in lieu of steel rebars, as the main flexural reinforcements in reinforced concrete (RC) beams have recently been suggested by many researchers. However, the development of FRP RC beam design is still stagnant in the construction industry and this may be attributed to a number of reasons such as the high cost of FRP rods compared to steel rebars and the reduced member ductility due to the brittleness of FRP rods. To resolve these problems, one of the possible methods is to adopt both FRP rods and steel rebars to internally reinforce the concrete members. The effectiveness of this new reinforcing system remains problematic and continued research in this area is needed. An experimental study on the load‐deflection behaviour of concrete beams internally reinforced with glass fibre‐reinforced polymer (GFRP) rods and steel rebars was therefore conducted and some important findings are summarized in this paper.

Details

Structural Survey, vol. 21 no. 4
Type: Research Article
ISSN: 0263-080X

Keywords

1 – 10 of over 34000