The behaviour of argon gas bubbles in the CC machine is described in the present ECSC project involving Irsid-TKS-CSM. Several approaches are combined and compared, namely water and numerical simulations, which show the same trends as observed on products. Process improvements could be defined in relation with the defects linked to argon gas in the tundish nozzles.

They have been applied to the production of plates, beams and bars for bridges, buildings and mechanical equipment. These products are characterized by a great metallographic homogeneity, high strength with minimized scatter, high toughness of the base metal and the welded joints, the possibility to weld without preheating, etc.

CRM has developed a mathematical model of the sintering process aiming to optimize the latter in terms of both performances and environmental impact. The model is able to simulate conventional sintering as well as original layouts like selective waste gas recycling with integrated desulphurization or steam injection at the sinter bed surface. The results (in particular CO and SO2 emission profiles) have been validated experimentally and also at the industrial scale.

SSSA is involved in the Subproject 9 Scenarios, Sustainability,Dissemination & Training, in particularly in the Work Package4. This KPI, developed at SSSA, measures the most importanteffects in the EU/Rest of the World Steel Trade due to theimplementation of a new technology: a quantitative approachhas been used in order to evaluate the EU raw materialdependence from the rest of the world and an approachboth qualitative and quantitative has been used in order tocalculate the variations in the EU competitiveness. An importantconsideration in the development of KPIs is the selection of theappropriate measurement categories. The selection is based,first of all, on the quantification of the European dependencethrough the weight of the non EU supplier countries andthrough the weight of the most important raw materials in theproduction process, then on the measurement of the Europeancompetitiveness. The article describes the methodology andthe algorithms applied in the steel sector. Finally, some resultsare shown and discussed.

The growth velocity during solidification of an undercooled melt of a Co-Cu alloyprocessed by electromagnetic levitation was measured using a high speed video camera.Applying a model of local non-equilibrium solidification, theoretical predictions ofdendrite growth velocity and dendritic growth radii are compared with high-accuracymeasurements of the growth kinetics. As the undercooling ΔT reaches a critical valueconsistent with the dendrite growth velocity being equal to the atomic diffusion speedVD in bulk liquid,ΔT =ΔT(VD),the velocity-undercooling relationship exhibits a break-point. A distinct change in thedendritic growth mechanism exists with the onset of complete solute trapping andchemically partitionless solidification of the core of the main stems of the dendritesoccurs. A complete transition to the thermally controlled growth of dendrites occurs atΔT =ΔT(VD)that leads to essential changes in the microstructure of dendritic patterns The phenomenonof dendritic fragmentation in Co-Cu melts, solidifying at ΔT <ΔT(VD),is discussed.

Transient ladle reactions in IF steel melts are simulatedexperimentally. It is found that when Al2O3 is thermodynamicallystable, Ti has the effect of modifying the inclusions as a resultof local super-saturation. When Al2TiO5 is stable, the inclusionmorphology appeared to change into smooth, non-facettedshapes. When Ti oxide is stable, the possibility of generatingsecondary inclusions during solidification was investigated.

A thermal fatigue test (INTHERPOL) was developed by EDF in order to study the initiationof cracks. These tests are carried out on tubular specimens under various thermal loadingsand surface finish qualities in order to give an account of these parameters on crackinitiation. The main topic of this study is to test the sensitivity of different fatiguecriteria to surface conditions using a micro/macro modelling approach. Therefore a 304Lpolycrystalline aggregate, used for cyclic plasticity based FE modelling, have beenconsidered as a Representative Volume Element located at the surface and subsurface of thetest tube. This aggregate has been cyclically strained according to the results issuedfrom FE simulation of INTHERPOL thermal fatigue experiment. Different surface parametershave been numerically simulated: effects of local microstructure and of grainsorientation, effects of machining: metallurgical prehardening, residual stress gradient,and surface roughness. Three different fatigue criteria (Manson Coffin, Fatemi Socie anddissipated energy types), previously fitted at a macroscale for thermal fatigue of 304L,have been computed at a meso scale, in order to show the surface “hot spots” features andtest the sensitivity of these three criteria to different surface conditions. Results showthat grain orientation and neighbouring play an important role on the location of hotspots, and also that the positive effect of prestraining and the negative effect ofroughness on fatigue life are not all similarly predicted by these different fatiguecriteria.

The crystallographic texture of a great number of polyethylene films manufactured by the film blowing process has been investigated by X-ray diffraction. Some films present a classical texture (c-axis in the machine direction), which can be interpreted using existing morphological models. Other exhibit an original texture (c-axis in the film thickness) and no satisfactory morphological model has been proposed until now.

The inclusion populations and the relevant inspection methods aredescribed with a particular emphasis on the SEM-FEG/EDS imageanalysis system. Then, the efficiency and the limits of the inspectionmethods are assessed by a new simulation approach.

Embrittlement of duplex stainless steels after aging below 500 °C is a well documentedphenomenon, usually attributed to the unmixing of the ferritic Fe-Cr solid solution,either by spinodal decomposition or by nucleation and growth of Cr-rich α′ phase,depending on aging temperature. Additional precipitation taking place during aging, likeNiSiMo-rich G phase or Cu-ε, are also known to participate to embrittlement, making thecomposition dependence of embrittlement kinetics even more intricate. In this study, longterm aging treatments, up to 2 years at intermediate temperature (250–400 °C), have beenperformed for various duplex stainless steels grades containing different alloyingcontents in Cr, Mo, Si, Ni and N. Impact toughness has been measured after each agingcondition, and an apparent activation energy could be deduced for the various grades. Thisquantity is a good indicator of embrittlement resistance. Fine microstructuralcharacterizations have been performed in the ferrite: composition before aging wasdetermined by EPMA, and precipitation state before and after aging was observed on TEM.The influence of alloying elements on the embrittlement phenomenon is analyzed on thebasis of these results and of driving force calculations performed onThermo-Calc®.

Assessing traditional iron and steelmaking processes from anenvironmental point of view and developing breakthrougheco-efficient processes for the future are major challenges forthe steel industry today. In the framework of the challengingEuropean project ULCOS, which stands for Ultra Low CO2Steelmaking, Life Cycle Assessment (LCA) was chosen toassess breakthrough processes that could be part of thefuture iron and steel making landscape and to comparethem to the reference classical integrated steelmill.
To carry out such a study we propose a new methodologicalconcept which combines LCA thinking with physicochemicalprocess modelling.
Physicochemical models were developed for each processesof the classical integrated steelmaking route in order togenerate the data required to draw the Life Cycle Inventoryof the route. Such a method bypasses the traditionaldata collection and brings accuracy to the inventory byintroducing rigorous mass and energy balances into themethodology.
In addition it was shown that such an approach allowstesting and assessing different operational practices ofthe processes in order to optimise the use of energy andthe CO2 emissions, which showed that it can be used as apowerful tool for eco-conception of processes.

Ironmaking is a mature technology that has reached over the last decades a high degree of excellence. It has proven its ability to adapt to the changing conditions regarding raw materials availability, energy resources and hot metal demand. The large development of coal injection practice has allowed reducing the dependency towards coke, while achieving total reductant rates close to the theoretical limit. New challenges, especially with respect to environment and CO2 emissions, will be strong drivers for technological progress. To meet these requirements, further improvements of performance are needed in the short term. Increased use of scraps will be an efficient solution. In the mid-long term, innovative and breakthrough solutions must be invented. An example is given by the concept of nitrogen-free blast furnace, involving recycling of decarbonated top gas and sequestration of CO2.

This paper is mainly devoted to the presentation and the illustration of chemical microananalysis methods. Four basic techniques will be successively presented: the energy dispersive X-rays spectroscopy (EDS), the wave dispersive spectroscopy of X-rays (WDS), the electron energy loss spectroscopy (EELS) and the Auger spectroscopy (AES). For each of them, the limitations and advantages will be presented.

In the present study, the main objective is to improve the mechanical properties of ahigh steel HSLA grade such as X80 for welded pipes. A study was conducted to optimise thethermomechanical treatment and to attain the mechanical properties of the X80 grade ofHSLA steels. From the same chemical composition of the hot rolled X60 grade Nb-Ti-Vmicroalloyed strip steel, we want to enlarge the production to the superior X80 gradetype. Dilatometry tests, hot torsion and hot rolling using a pilot mill allowed thesimulation of operating process sequences. The results of the rolling schedules performedin a pilot mill allowed us to analyse the effect of the deformation parameters(temperature conditions and reduction) on the evolution of the final structure and themechanical properties of the Nb-Ti-V microalloyed steel.

A new technology for separating and recovering iron and zinc from EAF exhaust gases is proposed. The process is composed of a coke bed filter and a new type of zinc condenser. Iron and slag components in the exhaust gas are collected in the coke bed filter. In this paper, the theoretical background and numerical analysis of the characteristics of the coke bed filter are introduced, and the experimental results concerning the collection of iron and slag components in a bench-scale coke bed filter are reported.

The first industrial twin roll caster for carbon steel strips is under construction on the Nucor site at Crawfordsville. This installation based on the CASTRIP technology developed by BHP and IHI is expected to produce 500 000 tons per year of hot rolled strip with a thickness below 2 mm. In this paper the characteristics of the CASTRIP technology are presented, with reference to the economical aspects and further details on the main breakthroughs that had to be accomplished to improve the efficiency. The twin roll caster technology offers many advantages in terms of production costs, environment and production flexibility over more conventional production routes for carbon strips with a thickness below 2 mm. It is expected that the implementation of the new technology will foster the user demand for ultra thin gauge hot rolled strips.

Nakayama Steel Works LTD. has succeeded in attainingthe cooling rate (105 -106 K/s) necessary for amorphouslayering technique by using the innovative idea ofimmediately cooling the spraying flame. Amorphous alloy(Fe70Cr10P13C7) formed by the new technique displays acorrosion resistance more than 500 times higher than the oneof SUS316L in aqua-regia immersion test, while the similarlyformed amorphous magnetic alloy film (Fe81B13Si4C2)indicates high magnetism of 15.4 kGauss in magnetic fluxdensity.

A very great number of arrowheads and arrows of catapult was excavated from "Le Puy d'Issolud" , probable site of the fight of Uxellodunum, given by Caesar, in 51 B.C. Till now, only a typological study was devoted to them. Here are gathered the first data about microstructure and local analysis (OM, SEM, EDXS, XR, microhardness HV) of weapons selected for their archaeological value. In the same time were made: examination of metal (Fe-C alloys, between pure enough iron and quasi-eutectoid steel), of corrosion layers and of the two types of residual slags, produced during direct reduction or forging. This contributes to reach a better approach of treatments and forging practice, during the Roman period.

VOEST-ALPINE Industrieanlagenbau (VAI) has developed highly efficient systems for the removal of dioxins from the offgas of conventional electric arc furnaces, as well as of shaft furnaces. These systems have been successfully implemented at industrial scale. This paper describes the components and working principle of these systems and gives information on the achievable emission levels.

This study aims at presenting a way to obtain nanostructured materials. Austeniticstainless steel (316L) nanopowders and ferritic/martensitic alloy steels (Fe14Cr) aresintered with the Spark Plasma Sintering (SPS) technique. This technique leads to a fullydense/nano-sized microstructure material after a short treatment. The optimal sinteringtemperature was found to be 850°C for both materials. The relationship between the Vickers Hardnessand scale of the microstructure is in good agreement with the Hall-Petch Law.