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This study aims at investigating the effect of bolt hole-making processes on the post-fire behavior of S235 steel plates.

A total of nine steel plates with a single bolt hole are tested. The single bolt holes are fabricated using three different hole-making processes: drilling, waterjet and plasma. Among the nine steel plates, three fabricated specimens are control specimens and are tested at ambient temperature. The six remaining steel plates with a single bolt hole are subjected to a complete heating-cooling cycle and then monotonically loaded until failure. The six fabricated specimens are first heated up to two different temperatures 800 and 925 °C, and then cooled back to the ambient prior to loading.

The results show that after being exposed to post-fire temperatures (800 and 925 °C), the maximum decrease in strength of the S235 steel plate was 6% (at 925 °C), 14% (at 925 °C) and 22% (at 800 °C) when compared to the results of ambient specimens for waterjet, drilled and plasma bolt holes, respectively. For post-fire temperature tests, drilled and waterjet bolt hole-making processes result in having approximately the same load-displacement response, and both have larger strength and ductility than those obtained using plasma cutting.

This study provides preliminary data to guide the steel designers and fabricators in choosing the most suitable hole-making process for fire applications and to quantify the post-fire reduction in capacity of S235 plates.

This study aims to report the oxidation behaviors of the T91 ferritic/martensitic steel (T91 steel) and 304 austenitic stainless steel (304 steel) in supercritical water (SCW) at 600°C.

The microstructure, elemental distribution and phase structure of the oxidation layers derived from the corrosion of the T91 steel and 304 steel were analyzed by scanning electron microscopy, Oxford Instrument X-ray spectroscopy, electron scattered diffraction and transmission electron microscopy.

The oxidation layers on the T91 steel and 304 steel have duplex structure. The two steels all suffer internal oxidation, and the phase of the internal oxidation layers are indexed as Fe-Cr spinel, although their morphologies are different. The formation of a continuous Cr-rich layer is not detected because of the relatively low Cr content of the steels, which is attributed to the corrosion property.

The accelerated corrosion and corrosion mechanism of the T91 steel and 304 steel with low Cr occurring in SCW at 600°C was clarified.

This paper aims to investigate the effect of characteristic parameters of pits on the mechanical properties and fracture model of cable steel wires.

The tensile test and finite element analysis of steel wires with corrosion damage were carried out. The stress development of corroded steel wire under corrosion morphology was studied by the 3D reverse reconstruction technology. The internal relationship between the stress triaxiality, equivalent plastic strain and pit depth, depth-width ratio of corroded steel wire was discussed.

With the increase of corrosion degree, the neck shrinkage phenomenon of steel wire was not significant, and the crack originated near the pit bottom and expanded to the section inside of specimen. The fiber area of corroded steel wire decreased while the radiation area increased, and the ductile fracture gradually changed to brittle fracture. The pit size significantly changed the triaxial degree and distribution of stress and accelerated the initiation and propagation of internal cracks at the neck shrinkage stage.

The proposed fracture model based on the void growth model could accurately simulate the fracture behavior of steel wires with corrosion damage.

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.

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.

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.

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.

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.

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.

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

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 (i_g) was 55 nA/cm². The corrosion observed in the stainless steel couple was in the weld area.

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.

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.

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.

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.

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.

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.

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.

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.

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

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.

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

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.

Stainless steel is rapidly achieving pre‐eminence as a favoured material of construction due, no doubt, to the fact that for many applications in chemical plant it is the only material that can fulfil the stringent requirements as well as ensuring minimum maintenance costs. This article describes the constitution of stainless steels and their physical, mechanical and corrosion properties. Finally, their importance to the chemical plant designer is surveyed.