The processes for direct and smelting-reduction of iron ores have, compared to the blast furnace, the advantage of being independent from coke. They will gain importance for mini mills based on the EAF steelmaking route. DRI capacity and production have steadily increased worldwide over the past three decades. DRI production in 2002 was 45 Mt and utilization of installed capacities reached 97%. A further increase in capacity and production is expected. The only smelting-reduction process under industrial application is the Corex process. The four operated plants in the world have in 2002 produced 2.66 Mt hot metal.

Model metal matrix composites are fabricated on purpose in this study in order to analyse damage initiation in heterogeneous metals. The materials consist in titanium matrices reinforced with SiC cylinders or aluminum matrices containing spherical zirconial/silica inclusions. The damage mechanisms of these materials are studied qualitatively and quantitatively using 3D non destructive imaging techniques (X-ray absorption radiography or tomography). In the case of the cylinders, the strain to failure of the SiC fibres as well as the interface shear strength can be directly measured. These measurements are the first attempts of direct determination of such parameters in heterogeneous materials. In the particulate composites, the strain to failure of the particles is determined using an inverse finite element calculation which validates the normal stress and stored elastic energy criteria for the rupture of the ceramic spheres.

In the last few years, CPM developed a first generation of charging model for coke ovens to improve the uniformity of oven filling and to reduce charging emissions. A new charging model has been recently built to simulate all kinds of charging process with 3, 4 or 5 charging holes and to obtain a more reliable representation of the levelling operation. More particularly, coal accumulation in each compartment of the leveller bar is represented, in order to have a better idea of the gas free space during the levelling operation. By using this model, it is now possible to suppress or reduce coal accumulation in the oven free space during the levelling operation and to obtain a constant and uniform coal profile at the end of charging, without gas emissions.

La Revue de Métallurgie is forever associated with the name of the great French Scientist who created it in 1904: Henry Le Chatelier. On the occasion of the centenary of the Revue, the authors draw an overview of its history that is intimately linked with the one of Metallurgy. More recently, la Revue de Métallurgie has been able to evolve permanently with a view to afford a better service to its readers. Other French journals have merged with the Revue and an electronic version has been introduced in 2000 as a tribute to the new century. Nevertheless other circumstances must now be allowed for, in an ever more global World with new European industrial groups and universities or engineering schools ever more focused on the international. From now on, Industry and Science, the preferred couple of Henry Le Chatelier, must be considered on a European basis. This shows the way for la Revue de Métallurgie in the Future.

During the normal growth of recrystallized grains in the metastable beta titanium alloy called Beta III, several parameters have an influence on the size of the recrystallized grains. The parameters considered in this study are: the amount of cold work, the initial grain size, the annealing temperature and time. The grain size distribution is determined by image analysis. The influence of each parameter is identified using a Taguchi type of experimental planning. From the results, the growth constants A and n are derived, as well as the activation energy Q of a growth model of the beta grain size as a function of annealing time and temperature for fixed initial conditions (amount of cold work, initial grain size).

After presentation of the historical background, the present structure of the Arab steel industry is described and its main characteristics discussed: insufficient domestic steel production, based on hot metal, scrap and mainly prereduced iron, high imports of semi-products, important development of the use of electric arc furnaces. Indications are then given on the rapid evolution of the steel industry in Egypt, Morroco and Saudi-Arabia, and on new, modern and larger capacity installations, in particular electric arc furnaces and rolling mills.

Since systems for examining coke quality are labour-intensive and time-consuming, automatic coke sizing and shaping equipment has been assessed. Variations in coke shape as well as size affect blast furnace permeability, so potential for replacing abrasion-resistance testing has been investigated by examination of size and shape changes between the oven wharf and the furnace. Results demonstrate the ability of on-line monitoring to facilitate coke quality assessment, permitting identification/correction of problems.

Steel slag is historically utilized as road pavement. However, there are many identified cases of problems related to cracks on the roads caused by steel slag volume expansion. In order to solve the volume expansion problem of the steel slag and to guarantee its use as road pavement with quality control even in high technical requirement projects with asphalt layer, Companhia Siderúrgica de Tubarão (CST) developed with a Road Consulting Company a treatment process to fit the steel slag to the characteristics demanded in road construction.

The dynamical resonant technique in free bending mode used for the determination of constants of elasticity has been developed in view to characterize coated materials. It has first been applied to homogeneous single coatings from room temperature up to 1,100°C for thicknesses varying from 2 to 200 μm with the help of a formalism of composite beam. This formalism has then been extended analytically to three and four layers in order to characterize multicoated materials. For thermochemical treatments presenting a gradient of mechanical properties, a simplified n-layer model allows to estimate the modulus gradient as a function of depth.

Blast furnace No. 1 of Companhia Siderúrgica de Tubarão has been in continuous operation for 20 years, accomplishing a high operational performance with high productivity and low fuel consumption. With a view to reach the major objective of 18,500 t/m3/IV of productivity, several works have been carried out in order to extend the furnace campaign until 2008. This paper presents the results of these activities along with a proposal for a new concept of hearth wear.

The discovery of Duralumin took place in a military context. The Prussian engineer Alfred Wilm had been mandated in Neubabelsberg near Berlin to develop such an improved alloy, the name of which is as much due to the fact that it is hard as to the fact it has first been industrially produced in Düren. International cooperations as well as harsh competitions have accompanied the first researches on this alloy in the beginning of the twentieth century.

In 2003, Sidmar commissioned the renewed blast furnace A at the Ghent works. It will operate together with the existing blast furnace B to provide an ironmaking capacity of 4.5 million t/year under optimal circumstances. The furnace was designed and constructed under an engineering contract with Paul Wurth and by a joint Sidmar engineering and project team. This will be the fifth campaign of blast furnace A. This paper describes the relining operations.

From his own experience, the author discusses the need of Metallurgy for theoretical models and their limits. The development of simple but less accurate models has provided a semi-quantitative approach of many complex metallurgical phenomena that has proven useful to orientate research as well as to afford interpretation-based prediction. Such models can be validated within a narrow range only. These approximate models could be substituted for by elaborated and comprehensive calculations that would provide reliable predictions with the help of ever more efficient computers. It remains a difficult task to take satisfactorily into account every internal parameter and boundary condition of a global system. Furthermore, any new observation requests another calculation that gives a clear picture but no comprehensive understanding of the underlying phenomena. Combining experiments, interpretation and prediction modeling along with few dedicated calculations may eventually allow further progress in such a complex domain as Metallurgy.

This article synthesizes a number of studies involving both quantitative characterization of precipitate microstructures (size and volume fraction) and modelling of precipitation kinetics. The main experimental methods used are Small Angle X-ray and Neutron Scattering and Transmission Electron Microscopy. The modelling is based on semi-analytical models (coupled differential equations) and on numerical models (based on the discretization of the precipitate size distribution). A variety of systems are studied, both aluminium alloys and steels. After considering isothermal precipitation, the issues of dynamic and non-isothermal precipitation are discussed. Finally, precipitation phenomena occurring during welding are characterized.

Belgo-Mineira, Arcelor Group, has at Monlevade Works one sinterplant with 120 m2 of strand area and its own iron ore mine (Andrade mine). Aiming to increase sinter production combined with the use of 100% of its own iron ore, the Hybrid Pelletized Sinter (HPS) process, developed by JFE (former NKK), was chosen among other alternatives. The HPS process started up at Monlevade Works in December 2002 and since January 2003 100% of Andrade iron ore has been used at the sinterplant. The contractual sinterplant productivity target (42 t/m2.24h) has been achieved.

We have developed an original method allowing to determine the elasticity constants of thin crystalline films deposited on substrates, which combines X-ray diffraction and in situ tensile testing. This technique has been successfully applied to measure the Poisson's ratio in tungsten thin films (150 nm) and molybdenum sublayers (8 nm) of a Mo/Ni multilayer. This paper gives the principles and experimental requirements for the Young's modulus determination.

The InterNOx project was carried out over a period of three years from October 2000. It benefited from a financial support by ADEME. The consortium of the project included Arcelor, Stein-Heurtey and Gaz de France. The purpose of this project was to promote the industrial implementation of these new burners in France and in Europe. It will make it possible to reduce CO2 and NOx emissions and to improve the performance of the reheating treatment of industrial products with new prediction models that have been validated on industrial or pilot furnaces.

Thermodynamic calculations have shown that chlorine can accumulate and cycle in the shaft of the blast furnace in the form of alkalis chlorides. Cycling of chlorine and alkalis in the upper part of the shaft was simulated at laboratory scale with a countercurrent reduction furnace (BORIS furnace) and also directly investigated at an industrial blast furnace. Experiments and calculations have shown the superposition of two cycles: one “pure” alkalis cycle in a large temperature domain, and a KCl cycle in a narrower range (600-1,000°C). According to the trials, effects of KCl on reduction and disintegration behaviour of sinter are similar to those of “pure” alkalis.