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.

L’acier inoxydable 304L est utilisé dans de nombreux domaines. Cependant, il peut, dans certaines conditions, être sensible à la corrosion par piqûration. Dans cette étude, nous nous sommes intéressés aux potentialités du traitement de fusion superficielle par laser nanopulsé pour l’amélioration de la résistance à la corrosion de cet acier. Ce traitement consiste à focaliser un faisceau laser sur la surface du matériau, provoquant sa fusion quasi instantanée sur quelques microns, immédiatement suivie d’un refroidissement ultra-rapide allant jusqu’à 1011 K/s. Les paramètres laser impliquent des modifications des propriétés physico-chimiques. Nous avons notamment étudié l’influence du recouvrement des impacts d’un laser à fibre ytterbium sur la résistance à la corrosion de l’acier inoxydable 304L dans des conditions d’une solution aérée, agitée de NaCl (concentration de 30 g/L). Nous avons obtenu une augmentation du potentiel de piqûration de l’ordre de 220 mV, traduisant une amélioration de la résistance à la corrosion. L’étude approfondie des modifications chimiques et structurales ne suffisent pas à elles seules à expliquer l’amélioration de la résistance à la corrosion. D’autres phénomènes doivent être pris en compte, comme la qualité de la couche d’oxyde, tant en terme de propriétés physico-chimiques, que mécaniques.

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.

This article presents the work carried out to define quality criteria of a new scrapsource for the steel industry: steel wires generated by grinding end-of-life tires. Thedefinition of this promising new secondary raw material source is perfectly in agreementwith the European Directives 75/442/CEE and 2000/53/EC, dealing with waste and recyclingof end-of-life vehicles, thus answering the environmental needs of our society.

Grindingtires generates an interesting secondary raw material (rubber granulates) but also twowastes, steel wires and textile fibers. We estimate that steel wires represent in Europe180 kt of steel every year which is not, or badly, valorized. This study showed that therecycling of these steel wires in steel mills was possible and viable, one necessarycondition being the determination of the non-metallic content remaining on the wires andkeeping it lower than 4%.

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.

The 4th Daughter Directive to the Air Quality Directive sets, for year 2012, a target value of 1 ng/m3 for the concentration of benzo(a)pyrene in ambient air. This target cannot be met at present in the ambient air of numerous coke plants. Operators are thus requested to take every reasonable measure in order to come closest to the desired air quality standard. Technical measures for minimizing benzo(a)pyrene emissions will focus on optimizing the pressure conditions in the oven chamber as well as on improving the sealing capabilities of coke oven closure facilities. The techniques for reduction of benzo(a)pyrene emissions, developed by Deutsche Montan Technologie GmbH, are presented.

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.

The observation and Raman analysis of the surface of a PET polymer after the impact of an aluminium particle, combined with thermal modelling, have shown the presence of a zone with modified crystallization. This heat affected zone, with a thickness of a few microns, has different shapes depending on the geometry of the splat particle which is at its origin. This is the sign of a sharp temperature increase followed by a very rapid cooling. As a result, the proposition of crystallized phase is gradually decreased, and an amorphous phase is formed in a thin layer close to the surface. These results have been used to develop a protective plasma spraying technique for the coating of organic parts.

The operation of blast furnace No. 2 started in July 1998, raising the CST yearly hot metal production from 3.6 Mt to the present level of 5.0 Mt. In July 2004, after a 6 years long operation, blast furnace No. 2 cumulated a production of 8.16 Mt, moreover ensuring good performance. The paper presents the actions that have been taken to control hearth wear, while sustaining high productivity and low fuel consumption. The results obtained are submitted to a detailed analysis with appropriate reference to the approach that has been followed and the controls that have been implemented.

After the desciption of the Perrin process in the first part of the paper, the second part deals with the socio-technical and enterprise aspects of the history of this process. The development block concept is used to analyse the different phenomena explaining the fate of this technical invention. The critical role played by Perrin himself is emphasized. The reasons why, despite favourable enterpreneurial conditions, the process was not more widely used are discussed.

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.


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.

Eko Stahl installed a roll gap lubrication system in stands F2-F4 of its HSM in 2001. The main objectives were energy saving, reduction of roll wear and vibration. The paper describes the equipment and its startup, the consequences of roll gap lubrication, looper angles and AGC, the cost saving results by energy saving and roll wear reduction. The influence on surface quality and environment is described as well as the ongoing optimization process.

Fatigue crack propagation in a welded joint of a cablecar post hasbeen developed, based on parameters measured on real joints. Itmakes it possible to optimise the schedule for inspection of theposts.

Ce travail est dédié à l’étude de l’endommagement en fatigue polycyclique soussollicitations multiaxiales de matériaux métalliques, suivant deux objectifs. Le premierest la caractérisation expérimentale de cet endommagement, pour des sollicitations simples(traction et torsion), mais également pour des blocs de sollicitations différentes. Lesecond objectif est la modélisation des phénomènes observés incluant l’usage de lamécanique de l’endommagement.

Cette modélisation est établie dans un cadrethermodynamique, suivant une description mésoscopique de la plasticité cyclique, avec uncouplage fort des variables décrivant le dommage cristallin. La version isotrope présentéeici utilise deux variables distinctes pour décrire l’endommagement du cristal. La premièrevariable permet de considérer les effets de la dégradation du cristal sur ses propriétésplastiques, alors que la seconde est une mesure équivalente de l’usure du cristal.L’évolution relative de ces deux variables dépend en premier lieu de la part hydrostatiquedu tenseur mésoscopique des contraintes.

The new casting-rolling plant of Thyssen Krupp Stahl AG is in operation since April 1999. Differences in comparison with other CSP plants are described. The production results at this time are explained together with the range of steel grades and the achieved dimensions. Differences with respect to conventional hot rolled strip are shown in surface quality as well as in mechanical properties and in dimensional tolerances.

Online detection and monitoring of phase transformation using non-destructiveelectromagnetic system in industrial hot strip mill processing of steels are reported. Thesystem renders wide range of possibilities for advanced control and fine tuning of the hotrolling and run-out table cooling parameters. These in turn allow for processmodifications to better control the microstructure of hot rolled bands. In particular,such modifications can attenuate the adverse effects of uncontrollable cooling of hot bandcoils that leads to severely non-homogeneous hot band microstructure. An example ofapplication is given demonstrating how reducing the non-homogeneity of hot bandmicrostructure with the aid of online hot strip mill electromagnetic system can helpeliminating the off-thickness defects in advanced high strength steel full hard stripsthus contributing to lowering the production costs and increasing the yield.

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.

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.

Especially in OECD countries, the reduction of primary energy consumption is a major taskto avoid further increase in CO2 emissions. Since 37% of the annual energyconsumption is related to the building sector, it is a major challenge for the future todevelop methods for significant improvement of the energy efficiency of building design,construction and operation. It has to be noted that the development of sustainablebuildings addresses both engineering and social aspects. From an engineering viewpointmethods to improve the ecologic efficiency of buildings by increasing the lifetime have tobe provided. From a social viewpoint these new approaches must take the future needs ofsociety into consideration. In addition, also governance structures and the regulatoryframework for the construction and operation of buildings need to be modified in thedirection of sustainability. The article will initially identify the major research topicsfor the development of sustainable design principles for buildings. Afterwards, structuralrequirements will be defined and translated into required property profiles for buildingmaterials. Herein, both mechanical and functional properties are of importance, so thatapproaches will be presented how to combine these properties in composite buildingmaterials. With respect to mechanical properties, new steels will have to be developedwith an improved balance of strength and ductility, so that some promising steel designconcepts will be shown. Additionally, new approaches for the failure assessment of thesenew steel types will be presented to enhance the exploitation of the characteristics ofthe innovative materials.