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Agency: European Commission | Branch: H2020 | Program: FCH2-RIA | Phase: FCH-02.4-2015 | Award Amount: 4.50M | Year: 2016

High-temperature electrolysis (HT electrolysis) is one of the most promising technologies to address the European Commissions Roadmap to a competitive low-carbon economy in 2050. Because a significant share of the energy input is provided in the form of heat, HT electrolysis achieves higher electrical system efficiency compared to low temperature electrolysis technologies. Therefore, the main objectives of the GrInHy project focus on: Proof of reaching an overall electrical efficiency of at least 80 %LHV (ca. 95 %HHV); Scaling-up the SOEC unit to a DC power input (stack level) of 120 kWel; Reaching a lifetime of greater 10,000 h with a degradation rate below 1 %/1,000 h; Integration and operation for at least 7,000 h meeting the hydrogen quality standards of the steel industry; Additional project objectives are: Elaboration of an Exploitation Roadmap for cost reducing measures; Development of dependable system cost data; Integration of a reversible operation mode (fuel cell mode); The objectives are congruent with the call FCH-02.4-2015 and the Multi Annual Work Plan of the FCH JU. The proof-of-concept will take place in the relevant environment of an integrated iron and steel works. Its existing infrastructure and metallurgical processes, which provide the necessary waste heat, increase the projects cost-effectiveness and minimize the electrical power demand of auxiliaries. As a result, the electrical efficiency of 80 % will be achieved by operating the HT electrolyser close to the thermal-neutral operation point. The installation will consist of an optimized multi-stack module design with 6 stacks modules in parallel (total capacity: 120 kWel). The last project year is dedicated to the testing of 7,000 h and more. This will be achieved due to a high degree of existing knowledge at system level. Lifetime and degradation targets have already been fulfilled at cell level and will be verified by testing an enhanced stack.


Zimmermann S.,Salzgitter Mannesmann Forschung GmbH | Karbasian H.,Salzgitter Mannesmann Forschung GmbH | Knoop F.M.,Salzgitter Mannesmann Grobrohr GmbH
Proceedings of the International Offshore and Polar Engineering Conference | Year: 2013

The results suggest that helical submerged arc welded line pipe is significantly better in terms of buckling capacity than expected on the basis of current design codes. The presence of a helical weld seam was not detrimental to the mechanical pipe performance, which is very much in line with the observations made in Zimmerman et al. (2004). Copyright © 2013 by the International Society of Offshore and Polar Engineers (ISOPE).


Flaxa V.,Salzgitter Mannesmann Forschung GmbH | Kluge S.,Salzgitter Mannesmann Forschung GmbH
Steel Research International | Year: 2016

Actual multiphase steels guarantee tensile strengths in different grades between 500 and 1000 MPa. Specifications and standards permit a wide field of chemical compositions. On one hand, carbon amounts higher than 0.12% are not seldom for grades exceeding 600 MPa tensile strength. However, frequently encountered difficulties during body manufacturing, due to limited formability, like enhanced crack formation at trim edges, increased spring-back, or deteriorated fracture behavior of weld joints are typically related to unfavorable microstructures. On the other hand, a strict limitation of the carbon content to below 0.1 wt% across all strength classes up to 1000 MPa allows avoiding the mentioned manufacturing difficulties. Carbon reduction as well as grain refinement and precipitation hardening by means of Nb-microalloying and solid solution hardening through further addition of manganese, silicon, chromium, or molybdenum are the major key factors on metallurgical site. A more homogenous combination of ferrite and martensite with certain amounts of bainite is adjusted by heat treatment to defuse the critical interfaces to increase forming properties measured by bending angle and hole expansion. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim


Genzel C.,Helmholtz Center Berlin | Krahmer S.,Helmholtz Center Berlin | Klaus M.,Helmholtz Center Berlin | Denks I.A.,Salzgitter Mannesmann Forschung GmbH
Journal of Applied Crystallography | Year: 2011

For a feasibility study of energy-dispersive residual stress analysis under laboratory conditions, an X-ray diffractometer that has been operated so far in the angle dispersive diffraction mode was equipped with a commercial tungsten tube and an energy-dispersive solid-state germanium detector. Starting from systematic investigations to find the optimum configuration regarding geometrical resolution, measuring time and stability of the applied detector system, different materials were characterized with respect to the near-surface residual stress state. The results achieved with the modified laboratory equipment within reasonable measuring times are in good agreement with synchrotron measurements performed on the same samples. With the example of a shot-peened Al2O3 ceramic with a highly non-uniform near-surface residual stress distribution it is furthermore shown that the different size and shape of the diffracting gauge volume used for the laboratory and synchrotron measurements might have a significant influence on the experimentally obtained Laplace-space residual stress depth profiles θ||(r). © 2011 International Union of Crystallography Printed in Singapore-all rights reserved.


Bendick W.,Salzgitter Mannesmann Forschung GmbH | Cipolla L.,Centro Sviluppo Materiali S.p.A | Gabrel J.,Vallourec Research Center | Hald J.,Technical University of Denmark
International Journal of Pressure Vessels and Piping | Year: 2010

A first assessment of creep rupture strength for steel grade X10CrMoVNb9-1 (Grade 91) was performed by ECCC in 1995. The results were included in the European standard EN 10216. Due to a significant increase of test data and test duration it was decided in 2005 to make a re-assessment of the extended database. Different procedures have been used independently by different assessors. The method with the best overall fit of the data set has found to be the ISO CRD method. This is characterized by a two steps procedure: in the first step the mean isotherms are evaluated from the test data, afterwards the evaluated isotherms are used for averaging by a Manson-Haferd master-curve. The results have been chosen as the basis to specify long term creep rupture strength values in a new ECCC data sheet for X10CrMoVNb9-1 (Grade 91). © 2010 Elsevier Ltd.


Panait C.G.,MINES ParisTech Center of materials | Panait C.G.,Vallourec Research Aulnoye | Bendick W.,Salzgitter Mannesmann Forschung GmbH | Fuchsmann A.,Vallourec Research Aulnoye | And 2 more authors.
International Journal of Pressure Vessels and Piping | Year: 2010

This paper presents results on the evolution of microstructure (both matrix and precipitates) of an ASME Grade 91 steel that has been creep tested for 113,431 h at 600 °C under a load of 80 MPa.The microstructure was investigated using transmission electron microscopy (TEM) and revealed chromium rich M23C6 carbides, MX-type precipitates, Laves phases and modified Z-phases. Only a small amount of modified Z-phase was found. In order to quantify coarsening of precipitates and growth of new phases during creep, the size distributions of the identified precipitates were determined by analysis of TEM images. In addition to this, the size distribution of Laves phases was determined by image analysis of scanning electron micrographs.Substructure modifications and creep damage were investigated on cross sections of the creep specimen using Electron Backscatter Diffraction and Scanning Electron Microscopy. © 2010 Elsevier Ltd.


Spiegel M.,Salzgitter Mannesmann Forschung GmbH | Mentz J.,Salzgitter Mannesmann Forschung GmbH
Materials and Corrosion | Year: 2014

Different alloys from ferritic-martensitic, austenitic, and nickel-based were exposed beneath a 60%NaNO3-40%KNO3 eutectic mixture in air for 500 h at 600 °C in order to estimate the corrosion loss of the different classes of alloys and to evaluate the corrosion mechanism. Investigations were carried out by metallography, SEM with EDX, and microprobe analysis. Ferritic-martensitic materials (P 92) show a significant mass gain compared to austenitic material (304 HCu) and nickel-based alloys. In particular Alloy 617 B suffers from pitting corrosion comparable to sulfate induced hot corrosion. The occurrence of internal nitridation is not clear and has to be evaluated. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Calcagnotto M.,Max Planck Institute Für Eisenforschung | Calcagnotto M.,Salzgitter Mannesmann Forschung GmbH | Ponge D.,Max Planck Institute Für Eisenforschung | Raabe D.,Max Planck Institute Für Eisenforschung
ISIJ International | Year: 2012

An ultrafine grained (UFG) ferrite/cementite steel was subjected to intercritical annealing in order to obtain an UFG ferrite/martensite dual-phase (DP) steel. The intercritical annealing parameters, namely, holding temperature and time, heating rate, and cooling rate were varied independently by applying dilatometer experiments. Microstructure characterization was performed using scanning electron microscopy (SEM) and high-resolution electron backscatter diffraction (EBSD). An EBSD data post-processing routine is proposed that allows precise distinction between the ferrite and the martensite phase. The sensitivity of the microstructure to the different annealing conditions is identified. As in conventional DP steels, the martensite fraction and the ferrite grain size increase with intercritical annealing time and temperature. Furthermore, the variations of the microstructure are explained in terms of the changes in phase transformation kinetics due to grain refinement and the manganese enrichment in cementite during warm deformation. © 2012 ISIJ.


Tasan C.C.,Max Planck Institute Für Eisenforschung | Diehl M.,Max Planck Institute Für Eisenforschung | Yan D.,Max Planck Institute Für Eisenforschung | Bechtold M.,Salzgitter Mannesmann Forschung GmbH | And 8 more authors.
Annual Review of Materials Research | Year: 2015

Dual-phase (DP) steel is the flagship of advanced high-strength steels, which were the first among various candidate alloy systems to find application in weight-reduced automotive components. On the one hand, this is a metallurgical success story: Lean alloying and simple thermomechanical treatment enable use of less material to accomplish more performance while complying with demanding environmental and economic constraints. On the other hand, the enormous literature on DP steels demonstrates the immense complexity of microstructure physics in multiphase alloys: Roughly 50 years after the first reports on ferrite-martensite steels, there are still various open scientific questions. Fortunately, the last decades witnessed enormous advances in the development of enabling experimental and simulation techniques, significantly improving the understanding of DP steels. This review provides a detailed account of these improvements, focusing specifically on (a) microstructure evolution during processing, (b) experimental characterization of micromechanical behavior, and (c) the simulation of mechanical behavior, to highlight the critical unresolved issues and to guide future research efforts. Copyright © 2015 by Annual Reviews. All rights reserved.


Calcagnotto M.,Max Planck Institute Für Eisenforschung | Calcagnotto M.,Salzgitter Mannesmann Forschung GmbH | Ponge D.,Max Planck Institute Für Eisenforschung | Raabe D.,Max Planck Institute Für Eisenforschung
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science | Year: 2012

Two plain carbon steels with varying manganese content (0.87 wt pct and 1.63 wt pct) were refined to approximately 1 μm by large strain warm deformation and subsequently subjected to intercritical annealing to produce an ultrafine grained ferrite/martensite dual-phase steel. The influence of the Mn content on microstructure evolution is studied by scanning electron microscopy (SEM). The Mn distribution in ferrite and martensite is analyzed by high-resolution electron backscatter diffraction (EBSD) combined with energy dispersive X-ray spectroscopy (EDX). The experimental findings are supported by the calculated phase diagrams, equilibrium phase compositions, and the estimated diffusion distances using Thermo-Calc (Thermo-Calc Software, McMurray, PA) and Dictra (Thermo-Calc Software). Mn substantially enhances the grain size stability during intercritical annealing and the ability of austenite to undergo martensitic phase transformation. The first observation is explained in terms of the alteration of the phase transformation temperatures and the grain boundary mobility, while the second is a result of the Mn enrichment in cementite during large strain warm deformation, which is inherited by the newly formed austenite and increases its hardenability. The latter is the main reason why the ultrafine-grained material exhibits a hardenability that is comparable with the hardenability of the coarse-grained reference material. © 2011 The Minerals, Metals & Materials Society and ASM International.

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