Three hundred years after the first production of coke, the history of this important breakthrough, an energy transition that, together with the invention of the steam engine, opened way to the industrial revolution, is still thought provoking on subjects such as the rate of change and the factors that are favoring or slowing down the rate of change, the role of infrastructure and technology in the development of industry, the role of protectionism or free-trade on technological changes and last, but not the least, the development of science and technology as tools for the improvement of the processes and products. From the first information of G. Jars and his metallurgical trips and the small scale tests of the first pioneers of the Enlightment, to the development of large size plants incorporating new technologies, this history is that of the important social switch from a small scale peasant seasonal activity with many workshops, to the large scale integrated industry concentrated in a few places and connected with the suppliers and the market by the new transportation infrastructure (canals, railways) developed in continental Europe throughout the XIXth century. Scientists (such as Ebelmen, Lecocq, Boudouard, Berthellot) and technologists (such as the innovation brought by Belgian furnaces) have played an important role in this mutation.

Following the Upper Bound Method (UBM), the velocity field in a rolling process is the one that minimises the power function [W. Prager, P.G. Hodge, Theory of Perfectly Plasticity Solids, Wiley, New York, 1951]. Generally, a family of velocity fields with few parameters is studied and the velocity field which minimises the power function is the best approximation of the real one. The lower the power, the better the approximation is. This paper presents a new family of velocity fields for the UBM approach of a rolling process in plane-strain conditions (2D). That family is based on the addition by an “oscillating perturbation” to a classic velocity field whose longitudinal component is constant in the strip thickness. We show that the best field of that family gives a better approximation than the classic one. This study proves there is an oscillating part in the velocity field during the rolling process. A careful observation of the fields obtained by a finite-element method, Lam3-Tec3 (1), shows that the oscillation phenomenon is in fact really present. And the oscillations predicted by the analytical model (UBM) match the FEM results very well.

This paper addresses issues of material flows in a selection of modern steel plants, especially the generation of wastes, from a social sciences perspective. I analyse key factors structuring waste management decisions through the case of “problem” wastes arising at a steel company’s plants. I discuss how some materials come to be construed as more problematical than others from a material and technological point of view, but also by taking into account organisational and legislative issues, in order to show that the construction of the “waste” category needs to be envisioned as resulting from a matrix of socio-material causes.

Le durcissement structural est un moyen important et efficace d’améliorer les propriétés mécaniques des alliages d’aluminium. Dans le cas de la série 6XXX (système Al-Mg-Si), une séquence de précipitation complexe s’opère, qui est significativement modifiée par l’ajout d’une quantité mineure de cuivre. Nous nous intéressons ici à l’alliage 6061 (Al – Mg 1 wt. % – Si 0,6 wt. % – Cu 0,25 wt. %). À 300 °C, des phases métastables proches, QP, QC et Q(′) co-existent lors de vieillissements de quelques minutes à une heure. Bien que de nombreuses études par TEM et HRTEM aient déjà été publiées sur cet alliage, les structures atomiques de ces phases ne sont pas connues avec précision. Ceci a motivé la présente étude en « STEM-ADF », qui contrairement à la TEM conventionnelle, est par essence insensible aux effets de diffraction et devrait ainsi permettre une meilleure description à l’échelle atomique. Nous montrons que la phase basée sur la phase Q est en fait identique à la phase stable Q-AlxCu2Mg12−xSi7 phase. Nous avons également précisé la structure de la phase QC : un modèle est proposé (groupe spatial Q-6), proche de la structure hexagonale P-62m préalablement identifiée par un des auteurs (C.C.). Nous discutons finalement la ségrégation du cuivre à la périphérie des précipités, ainsi que les relations structurales entre les phases QP et Q(′).

Materials have been central to the development of civilization, as they constitute the backbone of our society and of our technology, as all things are made of materials and all of them are made by tools mainly made of metals, and especially iron and steel. In modern language, they have become central to the sustainability of our society. Speaking about or measuring this relationship, however, is complex. Life Cycle Thinking is an important tool for doing this, but it was not developed with materials in mind and it focuses only on that small part of sustainability related to environmental impacts. Economic and societal issues require other methodologies and all these complementary visions have to be aggregated in order to report properly on sustainability matters. To advance towards such a new tool, called the New Metrics, an Initiative called SOVAMAT was launched 10 years ago and a Community has shaped up, binging together academics from a broad array of hard and soft disciplines, materials producers from metals to plastics, glass, paper/cardboard, concrete, carbons, wood, etc., and materials users, including meta-users who work on ecodesign, for example. The agenda of the Initiative is moving forward, improving existing methodology, extending it and aggregating various tools towards the final target of the New Metrics. The SOVAMAT Community meets regularly in annual seminars called Society and Materials or SAM. This paper explains the questions addressed by the Initiative and some of its early successes.

The scientific investigation involves the examination of copper alloy nails dated back to the Roman Age. The artifacts were retrieved from a shipwreck discovered offshore Elba island (Italy). Further carbon dating measurements indicated the origin between 140 and 300 AD. This work includes a brief overview of the ship’s routes and fortunes in order to give some context to the metallographic investigations. The experimental procedure involves the use of both Optical and Scanning Electron Microscopy (OM and SEM) coupled with EDS and EBSD probes. The attention has been focused on the metallurgical features of the nails with the intent of casting some light on the metalwork processes of the Roman Age. The scientific trials revealed a “brazed” joint, which allowed to learn more about the applications of this technique during this historical period. In addition, the textural analysis yielded a strong work-hardening, evidence of an intense cold shaping procedure in use by the Roman blacksmiths.

This paper presents a probabilistic method for fatigue life estimation within the frequency domain for structural elements subjected to multiaxial random loadings. Multivariate Monte Carlo Simulation is used to account for the correlation between the stress components and their different probability of occurrence and, moreover, enables stochastics during damage analysis to be allowed for and, at the same time, uses any suitable, material dependent multiaxial fatigue criterion known from the time domain. Comparison of the evaluated fatigue damage with experimental results from vibration tests on a demonstrator, chosen from common application fields in the automobile industry, shows good correlation.

The operation of an economy is supported by the stock of materials in the form of durables and infrastructure such as machinery, equipment, buildings, and structures. The amount of durables and infrastructure or “capital stock” in the economy is of great interest in the literature of economics, and is usually measured in monetary terms based on the data on capital expenditure. In spite of its wide use by economists, this measure of “capital stock” is of very limited use for sustainable management of material stock because of its neglect of physical properties such as the mass and material composition. This paper proposes a new method of measuring the stock of long-lived durables and infrastructure in terms of the mass of its materials. This method is based on the WIO-MFA method [S. Nakamura et al. J. Ind. Ecol. 11 (2007) 50-63] and the capital formation matrix that is one of the supplementary tables of the input-output table. The method is applied to the Japanese input-output data with 400 sectors, with 9 types of metals (iron, ferroalloy, copper, zinc, lead, tin, aluminum, silver, and gold) and 8 types of plastics (thermo-setting resins, PE (low), PE (high), PS, PP, PVC, high-performance resins, and other resins) occurring as materials. It was found that substantial variations exist among sectors while fixed capital formation in the year 2000 weighs 518 kg per million Japanese yen on average in metals and plastics.

In this paper, a non-destructive method is proposed for measuring the density of a very thin lubricant layer (weight and spatial) on an industrial surface. We considered spectroscopic ellipsometry measurements on rough tinplated steel substrates protected by a lubrication layer. The thickness of the coating was less than the roughness parameter characterizing the metallic surface. As the optical properties of the substrates could not be modelled in a conventional way due to the roughness and the complex structure of the metal, the variations of one of the ellipsometric angle (Δ) were evaluated as a function of the lubricant film surface density. After identification of the potential outliers using a multivariate analysis technique based on the Mahalanobis distance, we interpreted the data using the Drude’s approximation for thin dielectric films. The values of Δ linearly decrease with the lubricant surface density, allowing us to evaluate locally the lubricant surface density and its point-to-point variations.

Development of metallic glasses is hindered by the difficulties in manufacturing bulk parts. We report on the preparation of glassy alloys using the spark plasma sintering of gas atomized powders. The Zr57Cu20Al10Ni8Ti5 alloy processed has a high glass forming ability. Densification is obtained at the glass transition temperature (390 °C) under high pressure (≈500 MPa). Systematic study of the effect of powder particles size and sintering time is performed through structural and thermal analyses. Local and partial devitrification of the amorphous alloy is detected, resulting from local temperature overshoots. From these analyses, an approach of the spark plasma sintering mechanism of metallic glasses is proposed.

Dans les secteurs industriels de l’énergie et du transport, les structures mécaniques sont soumises à de forts niveaux de contraintes dynamiques qui impactent grandement le niveau de durabilité de ces dernières. Dans un contexte de réduction de coût de possession et d’extension de durée de vie, les industriels sont conduits désormais à bien maîtriser la fiabilité mécanique de leur produit. Pour ce faire et de part la nature stochastique des chargements dynamiques, les méthodes utilisées sont celles de la fatigue vibratoire, basées sur des représentations fréquentielles, tant au niveau du schéma modal de la structure, qu’au niveau de la définition de ses processus d’excitation et de contrainte. De ces considérations techniques, le présent article fait le tour des méthodes de calcul utilisées en fatigue vibratoire et compare les méthodes de comptage Peak-Valley (PV) avec celles du RainFlow Counting (RFC), reconnues comme les moins conservatives et donc les plus pertinentes, en terme de prédiction de durée de vie. En ce qui concerne les méthodes Peak-Valley, les modèles historiques de Rice [S.O. Rice, Bell Systems Technical Journal 23 (1944) 282-332; 24 (1945) 46-156] et de Miles [J.W. Miles, J. Aeronautical Sci. 21 (1954) 753-762], développées en 1944 et 1954, sont pris comme référence et comparés aux modèles RainFlow Counting de ces dernières années. Pour ce faire, l’étude comparative se basera notamment sur les approches empiriques de Wirsching-Light [P.H. Wirsching, M.C. Light, J. Structural Division ASCE 106 (1980) 1593-1607], et semi-empiriques de Dirlik [T. Dirlik, Application of computer in fatigue analysis, Ph.D. thesis, University of Warwick, 1985], développées respectivement en 1980 et 1985.

La mesure précise des champs de contraintes autour de précipités inclus dans une matrice cristalline est nécessaire à la compréhension de l’interaction entre les dislocations et les précipités de matériaux structurellement durcis. Ces interactions contrôlent le mouvement des dislocations, et donnent donc des informations sur les propriétés mécaniques des matériaux. Les champs de contraintes autour des précipités de petite taille peuvent être obtenus à partir d’images de microscopie électronique en transmission en haute résolution (METHR) en utilisant la méthode des phases géométrique (GPA). Cette méthode est utilisable de façon générale pour caractériser les contraintes à l’échelle nanométrique autour des précipités de structure complexe ou inconnue et est appliquée ici dans les cas de l’alliage d’aluminium 2198. Dans ce matériau, il est montré que les champs de déformation autour d’un nanoprécipité en forme de disque et d’épaisseur faible peuvent être modélisés par ceux d’une dislocation dissociée.

The maximum (or extreme) response and fatigue damage spectra can be used for the severity comparison of several vibration with two criteria, the largest stress and the fatigue damage created on a linear one degree of freedom system. After defining these spectra, it is shown how they can be used to write a test specification from the life cycle profile of an equipment.

In this presentation, the development of a simulation model that can examine the long-term strategy of materials industries, called a material strategy model, is proposed. This model has the following structure: first, the world is divided into a number of areas and a scenario for the demand for end products in the future in each area is provided. Then, the system required to realize the scenario and to minimize CO2 emission or the total cost is calculated using this model. In other words, the optimization to select processes in society to minimize total CO2 emission or total cost is carried out. As a result, the possibility of the long-term scenario; for example, the amount of car production based on population increase and GDP growth, can be discussed by considering CO2 emission and consumption of resources. A few simulation models to discuss long-term strategy have been developed in the field of energy system studies. In the energy system model, only a few resources such as coal, oil, natural gas and uranium are considered, but, in the material strategy model, it is necessary to examine many materials and resources. In addition, the material strategy model should have an energy model as one part of the model. As a first step, a prototype model mainly focusing on iron and steel with their alloys should be developed to show the capability to develop the whole model.