From a physical chemistry standpoint, the steel industry uses energy and emits greenhouse gases to make steel and byproducts. In the case of slag, which is sold and substitutes for natural resources, ironmaking and steelmaking processes are more efficient. This certainly sheds a new light on the CO2 intensity of products made from slag.

A certain number of changes have been made on the occasion of the relining of blast furnace B at Ghent. They oncern the design of the furnace and the improvement of its cooling system, the repair of the hot blast stoves, the replacement of part of the control equipment and the installation of new measuring devices. Environmental controls and improved working conditions were also at the origin of some changes. The result of this operation is a fine new furnace equipped with the latest measuring and control systems.

During the Bronze and Iron Ages, seven metals and about ten alloys were employed in the Western world. The manufacturing processes used by craftsmen (casting, hammering, finishing) for the copper base alloys are examined and discussed from the archaeological and metallurgical points of view. Some results obtained in Burgundy, dating from the 1st century BC to the 3rd century AD, permit tentative conclusions to be drawn regarding workshop organization and mass production.

Parts are produced from steel powder in a two step process : the powder is first compressed in a hard matrix and then sintered under a reducing atmosphere. During the second step, the part may be submitted to non-isotropic strains. Based on different experimental set-ups, the effect of the applied strain on the part deformation anisotropy has been assessed. This anisotropy increases with the density of the raw compressed material. The actual viscosity of the material has been derived from the measured strains with the help of a simple analytical model. The possible application of these results, to predict the shape alterations of industrial parts during sintering, is then discussed.

At the design stage of engineering structures, the fatigue behaviour is generally not included in the analysis. Shoulder reinforcements may be machined with too small blending radii. Even if fatigue is taken into account, the influence of the environment is almost always ignored. This paper shows that corrosion-fatigue is not an uncommon cause of failure in industry and that it may result in significant damages. The survey of such failures and the observation of the fracture surfaces allow to identify the typical features of this phenomenon.

Electrochemical methods are currently used to characterize the corrosion properties of metals. However, because of the easy use of these methods, the interpretation of the results could be sometimes difficult or wrong in terms of the metal corrosivity. This paper presents some precautions concerning the use of electrochemical methods devoted to characterize, to compare and to control metals. The discussion about these methods is a good way to establish the electrochemical criteria that they can produce.

LKAB's experimental blast furnace with a hearth diameter of 1.2 m and a working volume of 8.2 m3 produces approximatively 35 tons of hot metal/day and, not the least, valuable information. The furnace is used for the evaluation of burden materials and combinations as well as of modified or new blast furnace operational concepts and equipments. Nine campaigns ranging from 6 to 11 weeks have been performed since the start up in 1997.

A better control of the scrap basket charging operation by measuring the real scrap density, a direct visualization device viewing inside the furnace to follow-up the melting progress, an assessment of the liquid bath height by means of a gas blown through a porous brick: three original techniques providing to the furnace operators new tools allowing an optimization of the working practice are described.

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.

CRM developed a probe determining the raw material trajectories in bell-less top charging, by measuring the force generated by the material stream on a beam, in function of its position in the furnace. A prototype probe was tested on an industrial blast furnace during its first charging after a relining. These trials allowed the determination of both coke and sinter trajectories for the various chute angles. These results were validated by measurements carried out simultaneously by Irsid with painted bars.

Various phenomena occur during the high temperature corrosion of materials: the formation of a scale or of volatile products, the change of the weight and of the size of the samples, the development of mechanical stresses, the variation of the structure and/or the composition of the substrate or of the corrosion products, Specific experimental methods are devoted to the recording of the variations of these different parameters. In this paper some of the most frequently used methods will be described and discussed.

Strip casting technology has many advantages, both technical and economical. In the Eurostrip project, this technology is applied to stainless steel at Krefeld (KTN) and to carbon steel at Terni (AST). The latest achievements of this technology are presented in this paper. Positive results are reported with respect to casting width, in-line hot rolling, in combination with in-line inductive heating. The technology is ready for industrial application.

Recycled steel accounts for 46% of the iron resource of the steel industry in the world and has generated a new production route, based on the electric arc furnace, that produces 33% of the world steel output. Recycling is fully integrated in the market economy and has gained experience and technologies that allow 75% of the steel of end of life products to be effectively recycled. Furthermore, allowing for a modicum of cautions, this recycling is sustainable, which means that it may be repeated indefinitely, a feature that can be claimed by few materials. The use of scrap to produce steel requires 75% less energy than the integrated production route, that means 92% less energy than what is required to produce the same amount of aluminium. The electric arc furnace also allows the recycling of zinc, which is easily separated from the galvanized steel sheets used in construction and automotive industry. A large project federating the contributions of industry and academia, led by USINOR, has been carried out from 1995 to 2000 to support the sustainable recycling of steel: the main results of the “Iron Cycle” are reported in this paper.

The newly developed VAI-CONR Chem system allows to determine continuously the chemical composition of liquid steel in any metallurgical vessel. It represents an enormous potential for process improvements. After extensive laboratory testing, the system was sucessfully tested at an industrial vacuum degassing plant. At the beginning of 2003, it will be installed at a new AOD converter.

Two shape memory steels of the types Fe-31Mn-6Si and Fe-18Mn-8Cr-5Ni-5Si have been used for the experimental study of the transformation plasticity associated in these steels with the martensitic transformation γ(fcc) → ε(hcp). This study shows that austenitic samples, submitted to small bending stresses, show transformation plasticity on cooling. The formation of oriented ε martensite and the volume change between the primary and the transformed phases are responsible for this behaviour. In Fe-Mn-Si types of steel, transformation plasticity is reversible by a mechanism of shape memory. In contrast with TRIP steels, the plastic strain in the steels studied disappears on heating. The degree of shape recovery depends on the type of steel and on the fact that the stress is maintained or released. In both cases, effects relative to stress induced martensite reversion are observed.

In this paper an extension of the sintering method at atmospheric pressure, already used for tool steels, is proposed for prealloyed duplex stainless steel powders. A wide temperature range is tested and the effectiveness of boron as activator of the process is investigated. In all the samples no evidence of liquid phase is observed ; the sintering process allows full density in case of no boron addition and it occurs by solid phase diffusion, enhanced by the presence of two phases, austenite and ferrite : this makes needless to add boron as activator. We obtain density and hardness values comparable with the “as-cast” ones, isotropic phases structure and γ/δ ratio of about 50/50 for the best sintering temperature (1150 °C).