Today, the numerical simulation of fluid dynamic phenomena(CFD) in steelmaking applications is state of the art. Thelatest simulation results for the BOF and AOD as well asthe thin strip casting process are described. The basicinfluence of the process parameters, e.g. blowing andstirring rate, vessel dimension, location of top lance, numberand arrangement of porous plugs, on the converter meltflow and mixing time is simulated. In the case of thin stripcasting, the free melt flow on the moving belt is influencedby an induced electromagnetic field. The respective MHD(magneto-hydrodynamic) is presented.

The performance of lubrication systems for cold double reductionrolling has been investigated. Pilot mill trials have been achievedwith direct and recirculated emulsion application as well as with pureoil to analyse the effect of lubrication by emulsion on role bite frictionand the associated speed effect. It is then attempted to define anoptimized lubrication system that combines the advantages affordedby the direct and recirculated application systems.

Deux grandes classes de procédés ont été employées par les forgerons d’aciers dès lepremier millénaire av. J.-C. A partir de deux exemples typiques nous montrons commentl’interprétation des examens métallographiques avec des outils modernes tels que MEB etMEBFEG permet de reconstituer ces techniques. Un échantillon de l’époque mérovingienneillustre la fabrication de lames figurées par multiples opérations desoudage puis forgeage. Un échantillon de wootz prélevé dans une lame du XVIIIesiècle illustre le forgeage du fameux acier fondu de Damas.

In Europe, like elsewhere, the share of steel produced by electric arc furnaces from scrap increases. As the amount of internal scrap has decreased considerably, the steel plants recycle more and more collected obsolete and capital scrap. This source of iron has increased rapidly and will continue to increase. In spite of that, some plants may have to include in their EAF charge prereduced iron coming from countries where natural gas is available at low cost.

Carmakers face ever more frequently the phenomenon of spring-back after stamping, especially with new high strength steels (HSS and VHSS). Renault and Arcelor have been working together for many years on the formability and spring-back of VHSS. Recently, they aimed at establishing a method to optimize die shape in order to compensate for the spring-back after stamping. A method, named “Outifo” has been developed in order to obtain by simulation, from the initial CADs of the part and its referential stamped die, a CAD of a die with a modified shape. This allows the real stamping part, after forming and spring-back, to recover as closely as possible the geometry of the theoretical part defined by the designer.

CPM developed a mechanical sensor to measure coke oven wall deflections. This sensor was used in Dunkirk coke plant under normal operating conditions and showed reversible deflections between 1 and 1.5 mm when plastic layers meet at the oven centre. Special blends, with a high content of low volatile coals, were charged in several ovens of the Drocourt coke plant. In those conditions, CPM noticed the same phenomena as in Dunkirk plant but also reversible wall deflections just after charging.

The topography of grain boundary thermal grooves in the Ni-rich NiAl is studied by the atomic force microscopy. It is demonstrated how the processes of grain boundary sliding and surface faceting modify the shape of the grooves. The quantitative theory of grain boundary grooving that takes into account the above complications is developed. The great potential of grooving studies for the analysis of microstructure evolution is emphasized.

With extremely high cooling rates, a combined laminar jet andspray nozzle design cooling facility is the most advanced tool forthe evolution of mechanical properties of high-strength steels. Themain metallurgical aspects of Accelerated Cooling (ACC) andDirect Quenching (DQ) are presented. Typical plate applicationsare brought up. Design, engineering and operational aspects ofmodern cooling facilities are explained. Of particular importancefor a homogenous cooling process is a powerful process controlfeaturing advanced process models.

The selective oxidation of three CMnSi steels with differentC levels was studied by XPS. The formation of a graduallycovering SiO2 film is observed until a transition temperatureabove which the oxide film disappears, resulting in a renewedappearance of metallic iron at the surface. This change inoxidation behavior is thought to be due to the SiO2 reductionby solute C which is thermodynamically favorable at hightemperature. At the same time the precipitation of a BN filmon the metallic surface was observed which prevented anyfurther oxidation.

This article tells in the form of a tribute to chairman René Damien, the founder of Usinor, the story of the French wide strip mills. The situation of the French steel industry in the 1950s is first recalled. The important decisions made to modernize this industry are then presented and the major milestones of the construction and operation of the hot strip mills of Denain, Serémange, Dunkirk and Fos are indicated.

The context of strong local sensitivity to dust emissions from an integrated steel plant like Sollac Dunkerque justifies the monitoring of the emissions of abnormally coloured smokes from this plant. In a first step, the watch was done "visually" by screening and counting the puff emissions through a set of seven cameras and magnetoscopes. The development of a new device making automatic picture analysis allowed to render the inspection automatic. The new system detects and counts the incidents and sends an alarm to the process operator. This way for automatic detection can be extended, after some tests, to other uses in the environmental field.

CST has among its priorities the sustainable development and basedon it the sinter plant unit has a commitment to reduce the atmosphericemissions, by developing actions that assure the continuousimprovement on process and the development of equipment linkedwith environmental control, and also with raw materials consumed inthe process. This paper aims at showing all evolutions on theenvironmental control at the sinter plant, with reference to dust andSO2 emissions, and also the visibility of the plume stack.

In spite of its shortcomings, the salt spray test is universally used to characterize the corrosion resistance of zinc based coatings. A working group has tried to improve its reliability by the introduction of a new calibration method of the equipment. The outcome of the work is the definition of a new testing procedure, presently adopted in France for the control of coated products delivered to the automobile industry.

To meet the demand for Interstitial Free and Bake Hardening steelgrades for the automotive industry, CST has developed a productionprocess for steels with ultra low carbon (<20 ppm), and low nitrogen(<30 ppm) levels, along with a narrow range of carbon content. Thenew process also ensures a high degree of cleanliness of the CCslabs.