A new 400,000 ton/year 2-stand temper and double reduction mill has started production in April 1999 at Dongbu Steel Asan Bay Works in Korea. This facility produces skin-passed and double reduced tin mill black plates. The line incorporates state of the art technologies including AC motor driven 4-high CVC mills and computer integrated automation systems. The line has the capability of producing products 600 mm to 1,250 mm wide and in gauges from 0.15 mm to 1.0 mm for skin-passed products and from 0.15 mm to 0.36 mm for double-reduced products. An outline and the features of the line as well as the quality characteristics of the products are presented.

In regard to the sustainability of future cities, an increase in sustainable energysources needs to be managed. Therefore, the German government decided on increasing theratio of green energy up to 20% by 2020. In accordance with this, offshore wind energyparks will be constructed, as they provide the advantage of lasting air cleanliness andpreserving natural resources. To ensure construction safety, wind energy mills areconstructed using ductile steels of large thickness. Here, an application of high-strengthsteels provides the possibility of reducing the amount of material while constructionsafety is still ensured. Considering the long life cycle of wind energy mills’ foundationstructures and the recyclability of the steel grades used, their construction becomes arelevant factor in reducing CO2 emissions. Furthermore, the use of less material reducesCO2 emissions.Due to existing safety concepts, however, the application of high-strength steels is onlyconditionally allowed. Thus, the current study concerns the development of a safetyconcept based on the existing concepts to allow the application of high-strength steels.Furthermore, as the structural steel parts need to be joined, an energy-efficient weldingprocess is utilised: electron beam welding. The structural steel parts and weld joints areinvestigated with respect to their mechanical properties by analysing their loadability incombination with safety concepts. The load on the material is evaluated to ensureconstruction safety. In addition to the investigation of safety requirements, the suppliedmechanical properties are investigated. As the weld joints show different properties fromthe base material, the joints are considered the critical part. The joints areinvestigated concerning strength and toughness. Afterwards the mechanical properties arecorrelated with the wind energy structures. The prevention of failure is fulfilled whenthe mechanical properties of the weld joints exceed the required mechanicalproperties.

The Clean Development Mechanism Project elaboration is reviewed,considering every step from the project design document conception,through validation, the approval by the national authorities andthe verification process.The whole development is pioneered by CST ArcelorMittal Brasil,aiming at carbon credits generation and GHG emission reduction.An associated objective is the promotion of sustainable development.The potential of carbon credits generation is estimated to be440,263 tons of CO2 over a CDM project period of 10 years.

Steel rolling technology has achieved such fantastic progress in the 20th century that it might be considered to have come to maturity.Actually, it remains nowadays the object of intense development thataffords further impressive improvements. The progress of rollingtechnology is fostered by a drastic global growth of the number ofrolling equipments on the order of 40% over the last 15 years. Itbenefits from a dedicated R&D effort based upon a large scope ofscientific knowledge. The 9th Steel Rolling Conference illustrates thispotent innovative approach and it offers a unique opportunity forfruitful exchanges between steel producers, equipment suppliersand steel users.

The fire resistance of structures is one of the main brakes concerning the development of steel in buildings. This handicap of steel is in order to disappear due to the results of recent researches that permit to dimension the steel structures by considering the natural fire and the active fire fighting measures. In the frame of an ECSC financed research, an interactive calculation software has been developed with the aim of enabling engineering offices to perform easily calculations under natural fire conditions. This paper describes this new tool that should contribute to the promotion of steel by making the dimensioning under fire conditions easier and more competitive.

Several parts of degraded organ pipes belonging to some organs produced in different periods (from the 18th to 20th century) and from different Italian geographical areas have been examined and investigated in order to identify the possible causes of the degradation phenomena. An analysis through DSC-DTA measurements has been performed to define the crystallographic transformation of the studied alloys and a metallographic analysis has been realized to point out the microstructural characteristics. The morphological analysis has been improved by SEM equipped with an EDS device which permits a quantitative chemical characterization of the intact zones and of the degraded ones. The presence of chlorides has been identified as the starting factor of the degradation phenomena.

A physical limit to the galvanizing speed exists over which the liquid film explodes completely and prevents any further wiping. This limit is presently estimated around 180-200 m/min. A dimensionless approach including the Weber and Reynolds numbers is proposed to be able to predict the occurrence of the phenomenon. Practically it comes out that nozzles tilted by 30° down to the pot can pushback the limit by 30 %. A maximal line speed around 220 m/min could thus be reached.

Fe-Al alloys containing 25 and 31.5 at. % Al have been studied by internal friction, X-ray diffraction and dilatometric analyses. These techniques show for the first time that two internal friction peaks appear during the change in long range order type which occurs during the precipitation at 300°C of the metastable phase B2(FeAl). These peaks correspond to the formation of two phases: the equilibrium phase Fe3Al and a new intermediate tetragonal phase θ.

In 2003, the blast furnaces in Sollac Lorraine faced the challenge ofensuring self sufficiency in coke while maintaining a constant productionlevel. This challenge has been taken up successfully byreducing the coke ratio and by increasing PCI. This was achieved bychanging the tuyeres conditions, by optimizing burden quality andburden charging and improving the wall heat control.

In spite of an extensive bibliography available, the solubility limit of carbon in ferrite is still uncertain (between 50 and 100 ppm at 600°C for example), and this is not sufficient for the improvement of steel processing. Therefore we have tried to establish as accurately as possible the solubility of carbon between 500 and 750°C in a low carbon aluminium killed steel using a thermoelectric power protocol, which enables to calculate the amount of free interstitials in a ferritic matrix from the amount of interstitials that segregate on dislocations after strain. The solubility limit has been determined at ± 2 ppm between 550 and 730°C, and described by the relation: C(%wt) = 6.63 exp(-11.8 kcal/mol/RT). At a time when metallurgical phenomena are more and more simulated, we believe that a similar procedure should be used for other experimental studies providing basic data for modelling.

CRM developed a probe determining the raw material trajectories in bell-less top charging, by measuring the force generated by the material stream on a beam, in function of its position in the furnace. A prototype probe was tested on an industrial blast furnace during its first charging after a relining. These trials allowed the determination of both coke and sinter trajectories for the various chute angles. These results were validated by measurements carried out simultaneously by Irsid with painted bars.

The finite difference method of the low-alloy wear-resistant steel quenching process wasstudied. The temperature field and cooling rate variation of thickness of 45-mmwear-resistant steel (NM450) were calculated for different quenching practices. Themicrostructure and hardness of quenched plates were examined. The results indicate thatwhen quenching started, the cooling rate was highest on the subsurface and decreasedgradually until the center of the plate. However, as the quenching progressed, the coolingrate distribution along the plate thickness was reversed. The cooling rate increasedlinearly when the heat transfer coefficient (HTC) increased from 0–10 000W/m2 K, and then the speed gradually slowed down until achieving the maximumcooling rate. Close to the plate mid-thickness, the maximum cooling rate was easilyreached. Compared with high-pressure (HP) quenching and low-pressure (LP) quenching, underthe HP + LP continuous quenching mode, it is possible to obtain a high critical coolingrate in the temperature range of 900 °C–400 °C and small temperature difference betweenthe surface and center below 400 °C. The microstructure and hardness distribution on theplate surface for the HP + LP quenching mode indicated 100% martensite on the surface andmartensite with a little granular bainite in the plate center, while the hardnessdifference in the entire steel plate was less than 7%. This study provided guidance forthe formulation and optimization of wear-resistant steel.

In March 2000, a new compact steelmaking plant of Suez Steel (Adabia, Egypt), erected by VOEST-ALPINE Industrieanlagenbau (VAI), has successfully been started up. With a Finger Shaft type electric arc furnace (FUCHS system), a ladle furnace and a 5-strand caster, this highly modern plant has a capacity of 600,000 t/year of structural steel billets. Since the start up, new production records are continuously established.

EU regulations to be proclaimed will insist on product life cycle, Health-Safety-Environment issues and they will further enforce new ecotaxes. Anticipating these demands would afford Steel a competitive advantage and would further improve its image. The objectives of coated steel products, both in terms of process and properties are presented. The new developments of high performance steel surfaces are highlighted.

This communication presents experimental observations of plastic deformation in submicronic metallic multilayers. As the length scale decreases down to the nanometer range, we evidence a major change in deformation mechanisms, plasticity becoming less localized as in traditional slip bands of dislocations. AFM and nanoindentation techniques are used in conjonction with more standard techniques to characterize plastic deformation.

In this paper, the effect of an annealing treatment on the microstructure, mechanicalproperties and electrical conductivity of a deformed Cu-12.8 wt%Fe composite prepared bythe “casting/cold working” process is investigated. The Fe filaments exhibit the shapecharacteristic in the as-drawn composite as the annealing temperature is lower than 500°C. When the annealing temperature is above 500 °C, the Fe filaments undergo theinstability process in terms of boundary splitting, coarsening and breakup gradually. Thetensile strength gradually decreases with increasing annealing temperature due to thecoarsening of filament spacing. The work hardening for the composite annealed above 600 °Cis slower than that annealed at a lower temperature. The electrical conductivity reaches amaximum of 60%IACS at a temperature of 450 °C for one hour of annealing, and it furtherincreases with increasing annealing time at 450 °C to reach a plateau of 68% IACS. Thecurve between the tensile strength and electrical conductivity under different annealingprocesses indicates that the optimum annealing temperature for the Cu-Fe composite is 450°C.

The demand for improvements in surface quality and increased productivity in industrial cold metal rolling requires a good understanding of lubrication mechanisms. The limitations are due to boundary friction, controlled by the physico-chemistry of lubricant additives. The phenomena are complex and require a simplified approach. Consequently, a new method was developed by using an UHV tribometer associated with surface analytical tools to simulate the molecule chemical reactivity toward surfaces.

Le but est d’innover dans le domaine des liaisons au sol en remplaçant une traverse d’un essieu arrière en acier à haute limite élastique par une traverse en matériaux composites : Fibre de verre et Epoxy; tout en conservant les mêmes fonctions qui sont : assurer une rigidité de torsion, lier et maintenir en position les bras de suspension, résister aux sollicitations mécaniques du cahier des charges (nid de poule, choc trottoir, ...), reprendre les points de fixation du bras de suspension. Cette étude tient compte de la problématique de la grande série : minimiser le nombre de pièces, géométrie simple, procédé de fabrication simple avec des cadences élevées, facilité de montage. La démarche employée est la suivante : étape de présélection et intégration des profilés dans le modèle numérique, choix de l’empilement du composite et optimisation, choix d’une solution, conception des interfaces, réalisation d’un prototype. Le gain de masse est significatif puisque la traverse composite avec fixation ne pèse que 3,9 kg à comparer avec les 12,4 kg de la traverse initiale.

A new SSMR process to produce ultra-fine-grained hot strip is introduced,featuring: closely spaced rolling stands, continuous highspeed rolling with moderately large reductions rolling, rapid interpasscooling and rapid finish rolling cooling. An ultra-fine-grained CMnsteel strip (1μm) is obtained with a 700 MPa yield stress. Aproper choice of the work roll diameter and a careful control of thefriction coefficient should make it possible to keep the rolling forceat a level compatible with the design capacity of a conventional rollingmill.

Cementite decomposition leading to the formation of the whiteetching layer (WEL) on the surface of rail tracks was investigated byelectron energy loss spectroscopy (EELS) in the TEM and by threedimensionalatom probe (3D-AP). It is shown that the carbonconcentration inside cementite laths undergoing severe plasticdeformation in the transition zone between the pearlitic substrateand the WEL remains stoechiometric. However there exists a boundarylayer at the ferrite/cementite interface where the carbon compositiondecreases, indicating that decomposition is an interfacialphenomenon. Carbon atoms diffuse into the ferrite and segregatealong structural defects leading to a heterogeneous supersaturatedcomposition in the white etching layer.