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

Grinding tires generates an interesting secondary raw material (rubber granulates) but also two wastes, steel wires and textile fibers. We estimate that steel wires represent in Europe 180 kt of steel every year which is not, or badly, valorized. This study showed that the recycling of these steel wires in steel mills was possible and viable, one necessary condition being the determination of the non-metallic content remaining on the wires and keeping it lower than 4%.

Les pièces de forge sont universellement reconnues pour leurs bonnes propriétés mécaniques, notamment en fatigue. L’approche proposée ici consiste à intégrer la simulation du forgeage dans le dimensionnement en fatigue des pièces forgées. Le fibrage et le taux de corroyage sont deux caractéristiques principales du forgeage. À l’aide du logiciel FORGE®, le fibrage est calculé tout au long des opérations de mise en forme. Ce fibrage, ainsi que les contraintes résiduelles, sont ensuite introduits dans des outils de dimensionnement pour améliorer la prédiction du calcul de durée de vie en fatigue. Les critères de fatigue actuels, basés sur des modèles isotropes, ne permettent pas de valoriser le sens long de ce fibrage, et par là les pièces de forge, car c’est en général dans ce sens que ces pièces sont le plus sollicitées. Une extension anisotrope du modèle de Papadopoulos est proposée sur la base d’une campagne expérimentale effectuée sur des éprouvettes prélevées à 0°, 45° et 90° par rapport à la direction de fibrage. Une modélisation à l’échelle micro (DIGIMICRO) permet également de mieux comprendre le rôle des inclusions sur les sollicitations en fatigue. La mise en place d’une chaîne de simulation virtuelle globale à l’échelle d’un composant industriel, associée à des modélisations microstructurales, permet de mieux comprendre et de quantifier le rôle du fibrage sur les propriétés en fatigue à grand nombre de cycles des pièces forgées.

The Arab world has been less affected by the financial crisis of 2008–2009 than many other regions of the world. As an illustration, the apparent steel consumption has been growing to a level of 40 to 45 Mt/year, like in China or India but not so fast. The steel production is also growing, but is still in the range of 15 to 17 Mt/year: the region is a large steel importer, around 30 Mt/year. It is interesting to note that this trade is, essentially, between the two sides of the Mediterranean Sea. Regarding the production, it must be remembered that this area has the special feature of being based on the direct reduction of the iron ores through the natural gas-based processes such as Midrex or Energiron (ex – HYL). Steelmaking is carried out in EAF (electric arc furnaces) and it must be noted that, in the Marrakesh congress, the Turkish delegation mentioned that a new company in this country is designing and manufacturing electric arc furnaces for mini-mills based on scrap. A last point has to be stressed: the diversification of the steel products made in the Arab world. After a time where the emphasis was on light long products (reinforcing bars and light profiles), the production is now moving to heavy products such as beams and tubes, and flat products.

Because of the importance of lightweight constructions, nowadays other materials are more and more substituting components which had previously been made of metals. The usage of short fiber-reinforced plastics instead of metals seems self-evident in many cases because of their high specific strength and the favorable manufacturing processes. For fatigue life prediction a simulation process was established, which takes into account the fiber orientation and distribution as a result of an injection molding simulation. Hypotheses for fatigue life prediction of orthotropic materials have been derived from a lot of tests on specimens, implemented in the standard fatigue software tool FEMFAT and verified so far with component tests.

Production processes of integrated steel plants, mostly based on coal as an energy source, produce about 2 tons of CO2 per ton of steel. As specific CO2 production has to be decreased by 20% in the mid-term (2020), immediate action is required to further decrease the specific energy consumption. The integrated plant is not energy self-sufficient as extra electricity must be bought from outside, but on the other hand, produces an excess of process gas that has to be used within the plant. Optimisation of the use of the internally produced gases is a key issue as either they are burned at the power plant with a conversion yield to electricity of about 40% and often much lower, or might be valued in the plant internal heat exchangers with a much higher efficiency such as  ~90% in the hot stoves or  ~65% or more in the present reheating furnaces. This paper shows that using the high-value coke oven gas as a chemical reactant (for DRI production) leads to significant extra metal production. From a global viewpoint, this extra metal production is almost carbon-free, as it requires only electricity for its manufacture.

The phases obtained in copper aluminium bronze alloy (Cu-10wt.%Al-2wt.%Fe) cast into a permanent mould were investigated. The parameters examined were the thickness of the graphite coating of the mould and its pre-heated temperature. The phases α and γ2 were detected as well as the metastable phases β′ and γ′. The intermetallics of the Fe-Al system were obtained in various stoichiometric compositions. The different cooling rates of the casting led to two mechanisms of transformation into α-phase grains out of the unstable β-phase, one being nucleation and growth producing needle-shaped grains, the other exhibiting a massive transformation into spherical grains.