CRM is studying the possibility to comply with stringent PMregulations by improving the collection efficiency of existingdedusting systems, in order to avoid investments in expensiveadditional abatement means. The idea is to agglomeratefine dust particles together or onto coarser ones by applyingultrasound to the dust laden waste gas flow, upstream of thededusting unit.

Textures and local orientations have been determined in copper alloys after cold rolling and annealing. The measurements show that for a strain below a given threshold a mixed “deformation-recrystallization” texture is obtained after a static primary recrystallization : the {100}<001> cube orientation becomes stronger as annealing procedes, but is not dominating in the final microstructure. Global texture determinations by X-ray diffraction coupled with local orientation measurements by EBSD (Electron Back-Scattered Diffraction) show that in materials cold rolled by 70 and 80%, the orientation changes at the very beginning of the recrystallization process (i.e. at nucleation) are crucial for the formation of the recrystallization texture.

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.

A portable system to measure strip vibration at the nozzles level on continuous galvanizing lines is presented. It consists of three inductive sensors: two sensors are located near the strip edges and the last one is at the centre of the strip. This system has allowed reproducible results, provided the appropriate calibration procedure is used. The device has been successfully implemented on three lines of Arcelor. Considering the effect of strip tension and size, the frequency and amplitude measurements confirm the trends that can be expected from numerical modelling. Amplitude is always increased by the gas cooling power in the tower. Strip tension has a predictable effect on the frequency peaks; however its effect on amplitude is more ambiguous. Other observations have been made concerning the effects of pot roll bearings and roll intermesh.

An innovative modelling strategy has been developed and validatedto help the design of steel reheating furnaces. A set of complementarysimulation tools has been used to rethink the furnace concept,namely the Digit@l FurnaceTM, from the burners to the global energysystem optimisation. Several Digit@l FurnacesTM are now in operationon hot rolling mills. Advantages in terms of pollutant emissions,operation costs and flexibility have been demonstrated on site.

Steel is a universal material and has reached a high level of sophistication in applications and recycling potential. Rules are indicated for maintaining the sustainability of recycling (DfR concept). Consumer goods should be designed so as to maximize metal utilization, which is the only economical solution to meet ambitious recycling levels. The present level reached by recycling in France is compared to those targets in order to identify how much more progress has to be made.

The coefficient of friction is one of the tribological factors that characterizethe process of multi pass hot rolling. Friction is strongly dependenton inter-pass and in-pass rolling and cooling processingparameters. It can be improved by application of hot lubricationunder specific conditions. This paper builds upon previous studies onthe application of a Coulomb-Norton friction mathematical model, tostudy the influence of hot lubrication for a range of rolling conditions,with a view to define conditions where lubrication is most effective.

Steel making based on scrap melting is a substantial sourceof electric disturbances, such as voltage fluctuations, flicker,harmonics and unbalance between phases: unless mitigated,they all will spread over the feeding grid, violate the gridcode, and disturb other users connected to the same grid.With SVC (Static Var Compensator) and/or STATCOM, griddisturbances can be efficiently and cost effectively mitigated,enabling the plant owner to meet the valid grid codes. Atthe same time, productivity can be increased and productioneconomy can be improved.
The paper presents SVC and STATCOM for steel plantapplications; goes into the latest technology, and highlights acouple of recent, state of the art installations and their benefitsin steel manufacturing.

The aim of this work is to produce metallic coatings onto a steel substrate type E335 in order to hardening and improving the tribological properties of contact surfaces. In this study, two different coatings of stainless steel 18/8 and molybdenum realized with and without bond coat in Ni-Al were sprayed using a thermal flame spray technique. The microstructures of the two deposits are obtained using an optical microscope (OM), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Measures microhardness under a load of 200 g, are performed on the polished surfaces of these two types of deposits. The wear and the determination of the coefficients of friction of the two deposits tests were performed in dry conditions. A pin on disc configuration on a tribometer type TE 91 was used with different normal loads and a sliding speed of 0.5 m/s. The results showed that the microstructures obtained by OM and SEM of stainless steel present a dense and compact microstructure. It contains a low porosity and unmelted particles in comparison with the coatings of Mo. In addition, it was found that the spray-coated stainless steel 18/8 exhibited higher microhardness, higher wear resistance and significantly low friction coefficient in comparison with those of Mo coatings.

In order to improve the blast furnaces stability and productivity, industrial trials with the aim of reducing the circulating alkali load in the furnace and tests on a laboratory scale have been performed. The mechanical behaviour (fines generation) during reduction in presence of alkalis of various iron materials loaded in the blast furnace (sinter, pellets, iron ores) has been characterized with a set of Boris trials.

Freckle defects were found in electro-slag remelting (ESR) ingots, which severely limitthe development of the larger-diameter ingots. The macrostructure and the composition ofthe freckles in a low-alloy structure steel ESR ingot were investigated to clarify thefreckle formation mechanism. The results shows that the freckles in the ingot were causedby the upward solute-rich liquid flow in the mushy zone, and the composition of thefreckles corresponds to that of the liquid, with a liquid fraction of 0.36 to 0.43. Therelative Rayleigh number (Ra), a freckle criterion considering the effect of atilted solidification front, was adopted to evaluate the freckle formation tendency in theindustrial-scale ESR ingots based on the results of the experiments, kinetic simulationand thermophysical property calculation. The calculated results of Ra are in good agreementwith the actual distribution of the freckles in the ingot.

A comparative study between the mineral coals used byArcelorMittal Tubarão has been carried out, aiming atdetermining complementing criteria to the current energy modelfor the mineral coals purchasing qualification used for injectionin the blast furnace. Material characterization techniques wereemployed allowing the mapping of the characteristics of thecoals which potentially affect the stability of the pig ironproduction process.


Using recent and more accurate data, the thermodynamic model of Ma and Janke has been extended to a five element system. The content of non-metallic inclusions has been investigated for two grades of duplex stainless steels after solidification. The chemical and morphological features of the inclusions were determined by SEM observations and EDS analysis for different cooling rates. The results are interpreted on the basis of the chemical-physical interactions in the Fe-Cr-Ni-Si-Mn-O system. They can be used to define the optimal oxygen potential pattern for the casting of this type of steel in foundries.

Salzgitter AG has a crude steel production capacity of more than 8 million tons. Its subsidiary Salzgitter Flachstahl GmbH produces hot strip, thin sheets and surface finished products as well as input stock for heavy plates and sectional steel. In February 2003, Salzgitter Flachstahl GmbH awarded a contract to SMS Demag AG for the supply of a single-strand slab caster including the building portion and all ancillary equipment under SMS leadership. A range of as many as 400 steel grades is cast on the two already existing bow-type continuous casters. The new caster has enhanced the grade range by adding in particular phosphor-alloyed and high-tensile steel grades, including HIC resistant as well as IF and C steel. This caster had to be designed in such a way as to be suitable for taking over production of one of the two existing casters in the longer term. Other goals of constructing a new, third slab caster were to increase the annual production rate of all three casters to a total of 4.7 million tons, to cut production costs, to improve the product quality and to safeguard slab production during the standstill and scheduled maintenance of one of the existing casters.

This paper describes a model for the simulation of the process of direct reduction of iron ore for steel production. The model is implemented through stand-alone software and the simulation results have been compared with real experimental data. The very good agreement between the actual and simulated data proves that the model, despite its relative simplicity, takes into account all the fundamental phenomena of iron ore reduction.

This paper addresses several experimental techniques, which have been developed and validated with the aim of assessing the mechanical conditions of service-exposed primary plant components, particularly from the point of view of fracture toughness. Such techniques are based on the use of specimens of small or even miniaturized size, as an alternative to the "conventional" methodologies described by commonly used test standards.

In order to extend the RH lower vessel campaign life and to recycle used retractories, MgO-C bricks were applied for the RH lower vessel. As a result, the campaign life of the lower vessel has been extended by approximately 15 % , compared with magnesia- chromite bricks normally used. It was further ensured that it was possible to refine ultra-low carbon steel under these conditions.

Hot tearing defects appear during the last steps of casting solidification of dendrites.The crystalline structure traps a small amount of liquid metal, which is depressed, andcavities are spontaneously initiated. Molecular dynamics (MD) simulations of pure iron areable to predict, on one hand, the high temperature elastic modulus of crystals, and on theother hand, the cavitation event in liquid metal and near the solid-liquid growth front.High values of elastic tensor components are predicted close to the melting temperature.We conclude that a weakening of the mechanical properties of the crystal is not the reasonfor failure initiation. The crystals are thinned by partial melting as the effect ofnegative pressure increases. The cavitation is spontaneously initiated under a very highnegative pressure. The cavity expands very quickly and applies a pressure wave to thethinned crystals. We propose that this crystal thinning/pressure wave coupling is able toinitiate cracks inside the crystal.

A quantitative method is described for the measurememnt of displacements and strains by high-resolution electron microscopy. The image is considered to be composed of periodic sets characterized by Fourier analysis. The local amplitude and geometric phase of lattice fringes can be determined in this way. The analysis of the phase distribution leads to the determination of the local lattice configuration. The method is illustrated by different examples and its application conditions are discussed.

The mechanism of cleanness improvement with bubbles isreviewed. Bubbling through the down-leg snorkel of a RHhas been modelled. This process was then experimented ona RH in POSCO, allowing a significant reduction of theinclusion content of slabs.