The Australian Pilbara blend lump ore, which entered the Chinese market in 2007, is aspecial blending ore. To master its behavior and effect in a BF adequately, themetallurgical properties and high temperature reactivity of the Pilbara blend lump ore andsix other kinds of lump ore were researched. The reasonable proportion and mixing patternof the Pilbara blend lump ore was studied by carrying out softening and dropping propertytests, and this provides technological support for practical production.

Mechanisms of deformation in an age-hardenable Ni-Mo-Cr alloy containing large precipitates of the coherent ordered phase were investigated. The dominant deformation mechanism in the examined alloy depended on the applied amount of strain: for low strains micro-twinning within the ordered precipitates and dislocation slip in the matrix prevailed; at higher strains the f.c.c. twinning became the major deformation mechanism. Micro-twinning within the ordered phase was size related - micro-twins occur in large precipitates at relatively small strains. Twinning within the ordered precipitates may occur in all possible twin systems. Ten out of twelve possible twinning systems lead to the formation of true twins, and the long range order is preserved in the twinned regions. Formation of shear bands at high strains destroys the long range order.

A new technology for lubricating the work rolls during hot rolling has been successfullytested in the finishing mill of ArcelorMittal Dunkirk. This new technology allows sprayingvery low quantities of pure oil on the work rolls to reduce the rolling forces by up to20% and with an increased efficiency of 50% compared with emulsions. The lubricant was apure natural oil without any additives.

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.

The projects of Arcelor innovation R&D aim at developments having a time to market from a few months, for the most advanced, up to the end of the decade, for the most futuristic. They are carried out in partnership with the automotive industry. Ultra-high strength steels are a recent major innovation. They offer an effective answer to the request for improved safety and reduced energy consumption and contribute to sustainable development. The author introduces three major innovative developments: new technologies for high strength steels implementation, new openings for an improved cost/weight saving balance, new surface properties, based on nanotechnology. It is the ambitious claim of Arcelor, now and for the future, to afford steel solutions for all purposes, in particular for the automotive industry. The Arcelor-Nippon Steel collaboration makes it possible to bring an even better answer to the request of customers for further developments.

Fluid flow phenomena are very closely related to the casting quality and surface finish of the cast part. In addition, the good quality of the casting product can be achieved by using an optimum gating system design. In this work, a vortex well, which is one of the important components of gating system design, is utilized in order to demonstrate its effectiveness in improving the mechanical and microstructure properties of the cast part. An X-ray radiography test was performed in order to investigate the porosity distribution in castings with different vortex well dimensions. The scatter of flexure strength results was quantified by Weibull statistics. Microstructure analysis was conducted by using a scanning electron microscope (SEM) to examine the microstructure of selected casting specimens produced from the vortex well design. By optimizing the vortex well design, porosity inside the casting was significantly reduced, while the mechanical strength and reliability of aluminum casting were further enhanced.

A fast-computing model for crown and flatness in hot strip rolling and plate rolling has been developed based on steady-state elastic-plastic finite element simulations and an elastic buckling analysis. A single, geometry-independent tuning coefficient needs to be identified for each steel grade family. As a result, the model can be efficiently tuned to production mills. Implementation into the set-up environment “CID” of the SOLLAC Méditerranée hot strip mill is presented.

Laser irradiation may alter the colour of certain pigments used in artworks. Owing to the increasing use of lasers in artwork conservation, this problem becomes extremely crucial especially in the case of a polychromy covered by environmental encrustation. X-ray diffraction analysis and optical microscopy were used to study the crystalline structure of selected irradiated pigments in order to identify the changes that take place upon laser irradiation. Two representative pigments were studied, cinnabar (HgS) and lead white (Pb(OH)2 2PbCO3). The results revealed a change in the crystalline phase or chemical composition, respectively, which can be barely detected owing to its superficial character, which is of a sub-micrometer scale.

The structural durability of welded structures is determined by theinteraction of different influencing parameters like loading mode,spectrum shape, residual stresses and weld geometry amongothers. Examples from plant, offshore, transportation and automotiveengineering show how these parameters influence the fatigue lifeand to what extent they are considered in design codes.

Duplex stainless steels are often used today in the oil and gas industry because of theirhigh strength and good corrosion resistance. New developments in arctic conditions and athigh pressure require the qualification of these materials at very low temperatures. Thispaper will present the results of an extensive test program dedicated to assessing thelow-temperature behavior of various heavy-wall duplex stainless steel forgings, hotisostatically-pressed (HIP) connectors and hot extruded pipes at temperatures down to –60°C. Several welding processes were also evaluated. The implications for thedesign of duplex stainless steel production facilities will be discussed.

PARE has developed an electrode wear monitoring system. Theyhave implemented such systems at the three electric arc furnaces(two DC, one AC) located in Luxembourg. The goal of these systemsis twofold: first it allows the steelmaker to continuously monitor itsgraphite consumption and relate it to the furnace operating conditions;second it allows a feedback to the electrode suppliers for qualitymonitoring.

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.

Improvements have been made to slab, bloom, billet and thin slab caster secondary cooling systems giving better control of strand surface temperature and quality. This has been achieved by a combination of laboratory-based tests of spray characteristics and heat transfer coefficient (htc), innovative mathematical modelling and detailed on-plant measurements of temperatures and spray conditions.

The efficiency of automatic flatness control systems in tandem cold mills is mainly based on the accuracy of the prediction models and on the selection of optimum control concepts. BFI, together with EKO Stahl, has recently developed and partly applied advanced flatness control strategies (providing online-adaptation of actuator action to thickness profile information and in-gap process condition towards a fully integrated flatness control of all stands) that are superior to conventional techniques and lead to significant improvements in strip flatness. The present article aims to demonstrate the principles, advantages and results of this work.

This study concerns the inhibition of the corrosion of the aluminium alloy 3003 in a solution of 3% NaCl by Li+, Mg2+, MoO42-, NO2- and CrO42- ions. The methods used are the determination of the polarization curves and the metallographic examination of the surface condition. The results obtained show that the tested ions inhibit the corrosion process.The comparative study of the effect of these ions shows that the Mg2+ ions are the most efficient ones in the temperature range from 25 to 65°C. The inhibition efficiency increases with the concentration of these ions and reaches a maximum value of 86% for 5 × 10-2 alloy. As a consequence, the gap between pitting and corrosion potentials becomes larger. At 75°C, Mg2+ ions tend to stimulate corrosion of alloy 3003 in the chloride solution considered.

The E911 steel grade has been developed from grade P91 to increase the creep properties at 600 oC through the control of vanadium, nitrogen and the addition of tungsten. Grade 911 shows a better creep performance than grade 91. Microstructure stability of both steels was investigated by isothermal ageing tests for up to 10,000 hours at 600 and 650 oC and their mechanical behaviour is compared. Results on welded joints have also been compared with base material.

Hot rolling and solution annealing of duplex stainless steels involve high temperature reheating steps in oxidizing atmospheres. The thin scale that forms on the surface is not easily removed because it contains oxide nodules that are deeply embedded in the underlying alloy. These nodules appear when the protective Cr2O3 layer becomes locally inefficient. At the same place, oxidation of iron and manganese is possible and less chromium is needed to develop the scale. Depletion of chromium in the steel beneath the nodule is then less important and pickling the plates becomes more difficult.

Steel velocity measurement in the mould has been carried out using a Karman vortex flowmeter. The sensor is based on Karman vortex streets, which occur when a flowing fluid encounters a fixed body. A linear relation exists between the velocity of the fluid flow and the shedding frequency of Karman's vortices, therefore by measuring the frequency, the velocity of the fluid flow can be calculated. The system consists of two consumable sensor rods, which are placed at either side of the SEN. With the end plates instrumented with additional thermocouples, it is possible to relate the differential velocity measurement to end plate temperatures.

Based on the balance equations of mass, partial mass,momentum and thermal energy, the pyrolysis processof non-coking coals using a counter-rotating twin screwreactor (TSR) is modelled by means of commercial CFDcode PhoenicsTM. In favour of good convergence of themathematical solution, a structured, cylindrical-polar gridis chosen. Variable filling and intermeshing degrees aretaken into account by blocking numerical cells in gasdomain and intermeshing domain instead of performingtwo-phase calculations in a body-fitted co-ordinate system.Viscous behaviour of the granular coals is expressed bymeans of a generalised Newtonian fluid and chemicaldecomposition is implemented with aid of distributedactivation energies.