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The purpose of this paper is to present results of an evaluation of dual‐phase and galvanized steel reinforcements in corrosive environments.

Low carbon steels were intercritically annealed at 740°C followed by water quenching to obtain dual‐phase structures with 37 per cent volume fraction of martensite dispersed in ferrite matrix. Dual‐phase and galvanized steel rebars were embedded in concrete cubes and immersed in 5 per cent NaCl solution for up to 100 days. Corrosion rate, tensile and macro as well as microhardness tests were performed. The dual‐phase and galvanized zinc layers were observed under scanning electron microscopy (SEM).

From all of the tests carried out it was found that dual‐phase steels exhibited better corrosion resistant properties and superior strength compared to galvanized steels.

The results reported show that dual‐phase steel can be a good candidate for reinforcement in concrete especially in aggressive and corrosive environments.

The present research work aims to study the effect of average beam power (laser process parameters) on the overlapping factor, depth of penetration (DOP), weld bead width, fusion zone and heat affected zone (HAZ) in laser welding of 304L and st37 steel. Back side and top surface morphology of the welded joints have also been studied for varying average beam power.

Laser welding of austenitic stainless steel (304L) and carbon steel (st37) was carried out using Nd:YAG laser integrated with ABB IRB 1410 robot in pulse mode. The selection of laser process parameters was based on the specification of available laser welding machine. Dissimilar laser welding of 304L and st37 carbon steel for full depth of penetration have been performed, with varying average beam power (225-510W) and constant welding speed (5mm/s) and pulse width (5ms).

Recrystallized coarse grains were observed adjacent to the fusion zone and nucleated grains were seen away from the fusion zone towards carbon steel. Overlapping factor and HAZ width st37 side increases with increase in average beam power whereas top weld bead width increases first, attains maximum value and then subsequently decreases. Bottom weld bead width increases with increase in average beam power. The mechanical properties namely microhardness and tensile strength of the welded joints have been investigated with varying average beam power.

In the recent development of the automobile, power generation and petrochemical industries the application of dissimilar laser welding of austenitic stainless steel (304L) and carbon steel (st37) are gaining importance. Very limited work have been reported in pulsed Nd:YAG dissimilar laser welding of austenitic stainless steel (304L) and carbon steel (st37) for investigating the effect of laser process parameters on weld bead geometry, microstructural characterization and mechanical properties of the welded joint.

Corrosive agent constitutes a major problem for constructions located in coastal areas, since it keeps affecting their durability. This phenomenon, in synergy with moisture and high temperatures, leads to premature deterioration of the structures. Under these conditions, the need for management of the problem of resistance of steel against corrosion is an issue of paramount importance and a challenge to the structural integrity and reliability. The paper aims to discuss these issues.

The need for management of the problem of resistance of steel against corrosion is an issue of paramount importance and a challenge to the structural integrity and reliability. In the present study, an effort was made to increase the corrosion resistance of the high strength and ductility dual-phase steel B500c category, with the use of different shot blasting processes, without any interference in the chemical composition or in the production mode. In particular, shot blasting treatment was used for both cleaning and creating compressive stresses on the surface of steel bars, according to the pertinent protocols. The modified samples were studied via both conventional characterization methods and electrochemical techniques.

Through the whole surface treatment process of B500c steel, a positive impact came about not only the corrosion resistance, but also the mechanical performance.

Shot blasting process aims to increase the corrosion resistance of high ductility dual-phase steel (B500c), without any interference in the chemical composition or in the production mode.

The purpose of this papaer is to study the effects of corrosion on bare and embedded in concrete steel bars and additionaly to study the impact on their mechanical behavior.

The mechanical properties on bare and embedded specimens of dual phase steel bar B500c were measured after tensile tests, before and after corrosion.

The results show superficial severe localized pitting corrosion of embedded specimens in contrast to bare specimens. Also recorded a significant influence of corrosion on the mechanical behavior of the embedded steel specimens in contrast to the corresponding bare specimens. The mechanical behavior of dual phase steel bar B500c, due to chloride induced corrosion, seems to be significantly influenced by the existence of local interactions and the intense of external pit depths of different inclusions (MnS and the FeS etc) close to the outer surface.

The originality in this paper is the research on bare and embedded specimens and the comparison between them and additionaly are presented SEM and EDX analysis with interesting findings.

The poor corrosion resistance of the ferrite-pearlite steel limits its application in marine engineering because of the enhanced galvanic effect caused by continuously accumulated cementite. Cr as one principal alloying element is commonly used to improve the corrosion resistance of steels. This paper aims to study the effect of Cr on corrosion behaviors of ferrite-pearlite steels in an acidic environment.

The tested steels were immersed in a simulated solution of 10 Wt.% NaCl with pH 0.85 for 72 h to evaluate the corrosion rate. After the immersion test, the corrosion morphologies and products were tested by scanning electron microscopy, energy dispersive X-ray analysis and X-ray diffraction. Meanwhile, an electrochemical workstation was used to study the electrochemical behaviors of samples.

At the initial corrosion stage, the corrosion rate increased in the sequence of Cr₀, Cr_0.5 and Cr₁ steels, which was because of the competitive effect between the area ratio and the driving force caused by alloyed Cr. However, Cr₁ steel exhibited the best corrosion resistance after a 72-h immersion test. This was because the alloyed Cr promoted the formation of protective Fe₂O₃ and FeCr₂O₄, which suppressed the preferential dissolution of ferrite and, thus, reduced the accumulation rate of carbides, resulting in the weakened galvanic corrosion.

This paper reports the role that Cr plays in the galvanic corrosion of ferrite-pearlite steels, which is important for the engineering application of ferrite-pearlite steels in marine environment.

The purpose of this paper is to investigate the ballistic impact response of square clamped fiber-metal laminates and monolithic plates consisting of different metal alloys using the ANSYS LS-DYNA explicit nonlinear analysis software. The panels are subjected to central normal high velocity ballistic impact by a cylindrical projectile.

Using validated finite element models, the influence of the constituent metal alloy on the ballistic resistance of the fiber-metal laminates and the monolithic plates is studied. Six steel alloys are examined, namely, 304 stainless steel, 1010, 1080, 4340, A36 steel and DP 590 dual phase steel. A comparison with the response of GLAss REinforced plates is also implemented.

It is found that the ballistic limits of the panels can be substantially affected by the constituent alloy. The stainless steel based panels offer the highest ballistic resistance followed by the A36 steel based panels which in turn have higher ballistic resistance than the 2024-T3 aluminum based panels. The A36 steel based panels have higher ballistic limit than the 1010 steel based panels which in turn have higher ballistic limit than the 1080 steel based panels. The behavior of characteristic impact variables such as the impact load, the absorbed impact energy and the projectile’s displacement during the ballistic impact phenomenon is analyzed.

The ballistic resistance of the aforementioned steel fiber-metal laminates has not been studied previously. This study contributes to the scientific knowledge concerning the impact response of steel-based fiber-metal laminates and to the construction of impact resistant structures.

To provide a selective bibliography for researchers working with bulk material forming (specifically the forging, rolling, extrusion and drawing processes) with sources which can help them to be up‐to‐date.

A range of published (1996‐2005) works, which aims to provide theoretical as well as practical information on the material processing namely bulk material forming. Bulk deformation processes used in practice change the shape of the workpiece by plastic deformations under forces applied by tools and dies.

Provides information about each source, indicating what can be found there. Listed references contain journal papers, conference proceedings and theses/dissertations on the subject.

It is an exhaustive list of papers (1,693 references are listed) but some papers may be omitted. The emphasis is to present papers written in English language. Sheet material forming processes are not included.

A very useful source of information for theoretical and practical researchers in computational material forming as well as in academia or for those who have recently obtained a position in this field.

There are not many bibliographies published in this field of engineering. This paper offers help to experts and individuals interested in computational analyses and simulations of material forming processes.

As it is widely known, corrosion constitutes a major deterioration factor for reinforced concrete (RC) structures which are located on coastal areas. This phenomenon combined with repeated loads, as earthquake events, negatively affects their service life. Moreover, microstructure of steel reinforcing bars has significant impact either on their corrosion resistance or on their fatigue life.

In the present manuscript an effort has been made to investigate the effect of corrosive factor on fatigue response for two types of steel reinforcement; Tempcore steel reinforcing bars and a new generation dual phase (DP) steel reinforcement.

The findings of this experimental study showed that DP steel reinforcement led to better results regarding its capacity to bear repeated loads to satisfactory degree after corrosion, although this type of steel has less stringent mechanical properties.

Additionally, a fatigue damage material indicator is proposed as a parameter that could rank material quality and its suitability for a certain application. The results of this investigation showed that the fatigue damage indicator can be used as an appropriate index in order to evaluate the overall performance of materials, in terms of strength and ductility capacity.

The secondary phase decreased the corrosion resistance because of the segregation of Cr and Mo. Therefore, this paper aims to study the precipitation condition and the effect of secondary phase with volume fraction on corrosion behavior.

Secondary phase precipitated approximately from 375°C to 975°C because of saturated Cr and Mo at grain boundary by growth of austenite. Therefore, heat treatment from 800°C to 1,300°C was applied to start the precipitation of the secondary phase.

The secondary phase is precipitated at 1,020°C because of segregation by heterogeneous austenite. The growth of austenite at 1,000°C needs the time to saturate the Cr and Mo at grain boundary. When the volume fraction of austenite is 56 per cent (14 min at 1,000°C), the secondary phase is precipitated with grain boundary of austenite. The secondary phase increased the current density (corrosion rate) and decreased the passivation. That is checked to the critical pitting temperature (CPT) curves. The 1 per cent volume fraction of secondary phase decreased CPT to 60°C from 71°C.

The precipitation of secondary phase not wants anyone. Casted super-duplex stainless steel (SDSS) of big size precipitates the secondary phase. This study worked the precipitation condition and the suppression conditions of secondary phase.

Manufacturers need precipitation condition to make high-performance SDSS.

The corrosion resistance of SDSS is hard the optimization because SDSS is dual-phase stainless steel. The precipitation of the secondary phase must be controlled to optimize of the corrosion resistance of SDSS. Anyone not studied the precipitation condition of secondary phase and the effect of secondary phase with volume fraction on corrosion behavior of SDSS.

In this study, super duplex stainless steel (SDSS) was heat-treated. The purpose of this study is to assess the effect of the cooling rate after heat treatment on the pitting corrosion of SDSS.

The heat treatment from 1,000°C to 1,300°C was applied to SDSS to check the effect of the cooling rate.

The heat treatment temperature produced a different SDSS microstructure, and the cooling rate led to the growth of austenite. The casted SDSS indicated the presence of heterogeneous austenite, and the precipitation secondary phase under 1.6 per cent precipitated to bare metal. By applying heat treatment and cooling SDSS, its corrosion resistance changes because of the change in the chemical composition. The cooling rate at 5,600 J/s has the highest critical pitting temperature (CPT) at 1,100°C, and the cooling rate at 1.6 J/s has the highest CPT at 1,200°C. Low cooling rate (0.4 J/s) made the secondary phase at all temperature range.

The effect of secondary phase not consider because that is well known to decreasing corrosion resistance.

Solution annealing is taken into account to optimize the corrosion resistance. But that is not consider the cooling rate at each temperature. This study assessed the effect of the cooling rate at each temperature point.

Manufacturers need to know the effect of the cooling rate to optimize the corrosion resistance, and this study can be applied in the industrial scene.

SDSS is hard the optimization because SDSS is a dual-phase stainless steel. Corrosion resistance can be optimized by controlling heat treatment temperature and the cooling rate. Anyone not studied the effect of the cooling rate at each temperature. The effect of the cooling rate should be considered to optimize the corrosion resistance.