TY - RPRT A1 - Klingelhöffer, Hellmuth A1 - Ledworuski, Siegmar A1 - Brookes, Stephan-Peter A1 - May, Thomas T1 - Computer controlled tensile testing according to EN 10002-1 Results of a comparison test programm to validate a proposal for an amendment of the standard N2 - Tensile testing according to EN 10002-1 is one of the basic mechanical tests to characterise the mechanical properties of metallic materials. This testing procedure has been regularly under development for many decades in order to modify and amend it and to bring it up to an up to date standard. Today tensile testing for quality control in metals manufacturing industry is routinely performed automatically with computer controlled testing machines. Due to economical needs of industry proposals were made by a European Standard Committee to amend the standard EN 10002-1. A European research project with the acronym TENSTAND was started to validate the proposed modifications of the tensile testing standard. The work package 4 of the project was to validate the machine control characteristics. A comparison test program was started with ten partners, 4 test piece geometries and 3 test parameters for 6 materials, partly with upper and lower yield strength and partly with 0.2 % proof strength to compare experimental results according to the proposal to modify the standard EN 10002-1. Initially testing in the strain control mode was introduced as well as switching of the control mode to crosshead control 1 and switching of the testing speed at appropriate points during the test. The comparison test was evaluated statistically and scientifically. The following conclusions were derived from the comparison test and summarised as recommendations to the standard committees. The scatter of the material properties were not significantly reduced by introducing the amended testing procedure. Few of the reasons for the continuously observed scattercan be identified as follows: The material properties are observed to be widely dependent on the testing speed. As a consequence the range for the allowed testing speed must be reduced. The closed loop control was not optimised sufficiently in some tests, the use of complicated testing machine software led to misinterpretation of software commands, individual testing equipment and implementation of the tensile testing procedure led also to scatter of the material properties which lay in a range of few percent. This is blurred by the inhomogeneity of the material. T3 - BAM Forschungsberichtreihe - 268 PY - 2005 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-1835 SN - 978-3-86509-318-3 SN - 0938-5533 VL - 268 SP - 1 EP - 44 PB - Wirtschaftsverlag NW CY - Bremerhaven AN - OPUS4-183 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Chen, W. A1 - Darowski, N. A1 - Zizak, I. A1 - Schumacher, G. A1 - Klingelhöffer, Hellmuth A1 - Wanderka, N. A1 - Neumann, W. ED - Chandra, T. ED - Torralba, Jose M. ED - Sakai, T. T1 - Measurement of Gamma/Gamma' Lattice Mismatch in Creep Deformed SIngle Crystal Superalloy SC16 Using Synchrotron X-Radiation T2 - International Conference on Processing & Manufacturing of Advanced Materials CY - Leganés, Spain DA - 2003-07-07 KW - Superalloy KW - Lattice mismatch KW - High temperature KW - Creep deformed PY - 2003 SN - 0-87849-919-9 SN - 0255-5476 N1 - Serientitel: Materials science forum – Series title: Materials science forum IS - 426-432/5 SP - 4555 EP - 4560 PB - Trans Tech Publ. CY - Uetikon-Zürich AN - OPUS4-2790 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Burlet, H. A1 - McColvin, G. A1 - Henderson, M. B. A1 - Garcia, J. C. A1 - Peteves, S. A1 - Klingelhöffer, Hellmuth A1 - Maldini, M. A1 - Klotz, U. E. A1 - Luthi, T. A1 - Wilcock, I. M. ED - Strang, A. T1 - Microstructural and Mechanical Performance Assessment of Diffusion Bonded Bimetallic Model Discs T2 - 6th International Charles Parsons Turbine Conference CY - Dublin, Ireland DA - 2003-09-16 PY - 2003 SN - 1-904350-20-8 SN - 1366-5510 N1 - Serientitel: Book / The Institute of Materials, Minerals and Mining – Series title: Book / The Institute of Materials, Minerals and Mining IS - 800 SP - 735 EP - 748 PB - Maney CY - London AN - OPUS4-2823 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Darowski, N. A1 - Zizak, I. A1 - Schumacher, G. A1 - Wanderka, N. A1 - Klingelhöffer, Hellmuth A1 - Chen, W. A1 - Neumann, W. T1 - Lattice mismatch in creep-deformed single crystal superalloy SC16 PY - 2003 UR - http://www.helmholtz-berlin.de/media/media/oea/web/pr_webseite/druckschriften/berichte/bessy/annualreport2002.pdf#page=283 SN - 0179-4159 SP - 283 EP - 285 PB - Berliner Elektronenspeicherring-Gesellschaft für Synchrotronstrahlung CY - Berlin AN - OPUS4-2491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Schumacher, Gerhard A1 - Klingelhöffer, Hellmuth A1 - Rehfeldt, T. T1 - Changes in lattice structure and microhardness during thermal treatment of a NiCoCrAIY alloy N2 - The stability of microstructure and the microhardness of a NiCoCrAlY alloy was studied after thermal treatment at high temperatures and subsequent quenching into ice water. The alloy revealed mainly two ordered phases, a gamma' phase with L12 lattice structure and a beta phase with B2 structure. The gamma' phase is shown to become unstable in the temperature range between 1073 K and 1373 K where it undergoes an order-disorder phase transformation. The low transformation temperature compared to pure Ni3Al is ascribed to deviations from the Ni3Al stoichiometry and to the additional alloying elements Co and Cr. The gamma'-gamma order-disorder transformation is shown to be attended by a decrease in microhardness of about 30 %. T2 - Symposium M: Thermal Barrier Coatings; MRS (Materials Research Society) fall meeting CY - Boston, MA, USA DA - 2000-01-01 PY - 2000 SN - 0272-9172 N1 - Serientitel: Materials Research Society symposium proceedings – Series title: Materials Research Society symposium proceedings IS - 645 PB - Materials Research Society CY - Warrendale, Pa. AN - OPUS4-1052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Österle, Werner A1 - Bettge, Dirk A1 - Fedelich, Bernard A1 - Klingelhöffer, Hellmuth T1 - Modelling the orientation and direction dependence of the critical resolved shear stress of nickel-base superalloy single crystals PY - 2000 SN - 1359-6454 SN - 1873-2453 VL - 48 SP - 689 EP - 700 PB - Elsevier Science CY - Kidlington AN - OPUS4-2366 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Chen, W. A1 - Darowski, N. A1 - Zizak, I. A1 - Schumacher, G. A1 - Klingelhöffer, Hellmuth A1 - Neumann, W. T1 - Lattice distortion in precipitates of single crystal superalloy SC16 under creep deformation N2 - Specimens of single crystal superalloy SC16 were creep deformed at 1223 K along [0 0 1] up to ±0.5% creep strain using stresses of -150 MPa and +150 MPa, respectively. Line widths and peak positions of superlattice reflections were measured by means of X-ray diffraction parallel and perpendicular to the load axis in the temperature range between 293 K and 1173 K. The line widths were found to decrease with the increase of temperature for both directions on the two specimens after tensile and compressive creep deformation. After both kinds of creep deformation the crystal lattice showed tetragonal distortion which decreased with increasing temperature. The tetragonality after tensile creep deformation was larger than unity while it was smaller than unity after compressive creep deformation. The peak positions and widths restored after cooling back to room temperature. The experimental results can qualitatively be explained by the creation of dislocations during deformation and their anisotropic arrangement at the γ/γ' interfaces. KW - Superalloys KW - Creep deformation KW - Lattice distortion PY - 2006 DO - https://doi.org/10.1016/j.nimb.2005.12.032 SN - 0168-583X SN - 1872-9584 VL - 246 IS - 1 SP - 201 EP - 205 PB - Elsevier CY - Amsterdam AN - OPUS4-12498 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Hähner, P. A1 - Affeldt, E. E. A1 - Beck, T. A1 - Klingelhöffer, Hellmuth A1 - Loveday, M. A1 - Rinaldi, C. T1 - Validated code of practice for strain-controlled thermo-mechanical fatigue testing KW - TMF KW - Thermo-Mechanical strain-controlled fatigue testing PY - 2006 SN - 92-79-02216-4 SP - 1 EP - 37 PB - Office for Official Publications of the European Communities CY - Luxembourg AN - OPUS4-12756 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Ledworuski, Siegmar A1 - Klingelhöffer, Hellmuth A1 - Brookes, Stephen-Peter A1 - May, Thomas ED - Pohl, M. T1 - Untersuchungen zum automatisierten Zugversuch für die Weiterentwicklung der Norm EN 10002-1 im Rahmen des Europäischen Forschungsprojektes TENSTAND T2 - Werkstoffprüfung - Konstruktion, Qualitätssicherung und Schadensanalyse CY - Neu-Ulm, Deutschland DA - 2004-11-24 KW - Zugversuch KW - TENSTAND KW - Dehngeschwindigkeit KW - Geschwindigkeitseinfluß KW - EN 10002-1 PY - 2004 SN - 3-88355-337-9 SP - 73 EP - 78 PB - Werkstoff-Informationsges. CY - Frankfurt AN - OPUS4-5608 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Darowski, N. A1 - Zizak, I. A1 - Schumacher, G. A1 - Klingelhöffer, Hellmuth A1 - Chen, W. A1 - Neumann, W. T1 - Temperature dependence of x-ray intensity profile FWHM of the gamma' phase in the creep-deformed single crystal superalloy SC16 N2 - High-resolution diffraction using synchrotron x-ray radiation was applied to study γ´ precipitates with an L12 superlattice crystal structure in the single crystal superalloy SC16 after creep deformation at 1223 K with a creep strain of ±0.5% for tensile and compressive loads, respectively. The measurements of full width at half maximum (FWHM) of 001 and 100 γ´ superlattice reflections were performed at various temperatures from ambient temperature to 1173 K in vacuum. The experimental results revealed that the FWHM of both reflections decrease with increasing temperature. It is well-known that changes in particle size and lattice distortion in materials could lead to a variation of FWHM. The observed behaviour is discussed in the light of both the above-mentioned aspects. The decrease in the peak width is mainly attributed to the temperature dependence of the internal strain state. KW - Creep deformation KW - Synchrotron x-ray radiation PY - 2005 DO - https://doi.org/10.1088/0022-3727/38/10A/038 SN - 0022-3727 SN - 1361-6463 VL - 38 IS - 10A SP - A200 EP - A203 PB - IOP Publ. CY - Bristol AN - OPUS4-11967 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Skrotzki, Birgit A1 - Brookes, Stephen-Peter A1 - Kühn, Hans-Joachim A1 - Sievert, Rainer A1 - Klingelhöffer, Hellmuth A1 - Pfetzing, J. A1 - Peter, D. A1 - Eggeler, G. ED - Khan, A.S. ED - Kabirian, F. ED - Liu, J. T1 - Axial-torsional thermo-mechanical fatigue of a near-gamma tial-alloy T2 - Plasticity '12 - 18th International symposium on plasticity and its current applications CY - San Juan, PR, USA DA - 2012-01-03 KW - TMF KW - Multiaxial fatigue KW - Titanium aluminides PY - 2012 SN - 0-9659463-0-4 SP - 187 EP - 189 PB - NEAT Press CY - Fulton, Maryland, USA AN - OPUS4-25325 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klingelhöffer, Hellmuth A1 - Matzak, Kathrin A1 - Kühn, Hans-Joachim A1 - Skrotzki, Birgit T1 - Einfluss des Auswerteverfahrens auf die Bestimmung von zyklischen Werkstoffdaten im Hochtemperatur-LCF-Bereich T2 - 28. VDEh Vortragsveranstaltung der Arbeitsgemeinschaft für warmfeste Stähle und der Arbeitsgemeinschaft für Hochtemperaturwerkstoffe "Langzeitverhalten warmfester Stähle und Hochtemperaturwerkstoffe" CY - Düsseldorf, Deutschland DA - 2005-11-25 KW - Normung KW - Low Cycle Fatigue PY - 2005 SP - 137 EP - 146 PB - Stahlinstitut VDEh CY - Düsseldorf AN - OPUS4-11560 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Brookes, Stephen-Peter A1 - Kühn, Hans-Joachim A1 - Skrotzki, Birgit A1 - Klingelhöffer, Hellmuth A1 - Sievert, Rainer ED - Pohl, M. T1 - Axial-torsionale thermo-mechanische Ermüdung einer near-Gamma TiAl-Legierung T2 - Tagung "Werkstoffprüfung 2007" CY - Neu-Ulm, Deutschland DA - 2007-11-29 KW - Titanaluminide KW - Thermomechanische Ermüdung (TMF) KW - Mehrachsige Belastung KW - Axial-torsional Belastung KW - von Mises Vergleichsspannung KW - Spröd-Duktil-Übergangstemperatur PY - 2007 SN - 978-3-514-00753-6 SP - 249 EP - 254 PB - Verl. Stahleisen CY - Düsseldorf AN - OPUS4-16318 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Brookes, Stephen-Peter A1 - Kühn, Hans-Joachim A1 - Skrotzki, Birgit A1 - Klingelhöffer, Hellmuth A1 - Sievert, Rainer A1 - Pfetzing, J. A1 - Eggeler, G. ED - K. Maruyama, ED - M. Niinomi, ED - S. Akiyama, ED - M. Ikeda, ED - M. Hagiwara, T1 - Axial-torsional thermo-mechanical fatigue of Ti-45 Al-5Nb-0.2B-0.2C T2 - 11th World Conference on Titianium (JIMIC 5) CY - Kyoto, Japan DA - 2007-06-03 KW - Gamma titanium aluminide KW - Thermo-mechanical fatigue KW - TMF KW - Axial-torsional loadings KW - Microstructure PY - 2007 SN - 978-4-88903-406-6 VL - 1 SP - 679 EP - 682 PB - Japan Institute of Metals CY - Kyoto AN - OPUS4-16669 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Loveday, M.S. A1 - Bicego, V. A1 - Hähner, P. A1 - Klingelhöffer, Hellmuth A1 - Kühn, Hans-Joachim A1 - Roebuck, B. T1 - Analysis of a European TMF inter-comparison exercise N2 - A major international inter-comparison exercise on strain-controlled thermo-mechanical fatigue (TMF) has been undertaken to validate a new European Code of Practice for TMF Testing and to provide underpinning information for an ISO Standard. This paper focuses on (a) distribution of samples of Nimonic 90, (b) the establishment of a protocol for testing and reporting results, and (c) the analysis of the results. Participants in the inter-comparison exercise comprised eight inner-circle partners who primarily used test pieces which were all manufactured at the same workshop, albeit of three different test piece geometries, and ten outer-circle participants who manufactured their own test pieces, of their own in-house geometry. Each participant undertook three repeat in-phase (IP) tests and three repeat out-of-phase (OP) tests. The tests were conducted at temperatures cycling between 400 °C and 850 °C, with a strain range selected to give a failure life of approximately 1000 cycles, resulting in a stress range of up to ~1000 MPa. The testing conditions were chosen following a preliminary evaluation of critical testing parameters. Results from solid circular and solid flat test piece geometries, together with hollow tubular test pieces have been compared. The influence of temperature measurement using different types of temperature sensors has also been investigated. In-house repeatability has been assessed, together with inter-laboratory reproducibility. The results have been correlated with modulus and thermal expansion data for individual tests. Initially, the largest contribution to scatter in the results was attributed to human errors in reporting the results, compounded by computer assisted ‘cut-and-paste’ errors. Once these obvious discrepancies had been corrected, it was possible to use the data sets to point to some recommendations regarding testing procedures that can be incorporated into the Code of Testing Practice [Hähner P et al. Code of practice for thermo-mechanical fatigue testing – TMF-Standard-Work Package 6 Report, September 2005] and provide technical underpinning for the ISO Standard. The results and the procedures used for analysis are presented. KW - Thermomechanical KW - Fatigue KW - Test methods KW - Analysis KW - Nickel-base superalloys PY - 2008 DO - https://doi.org/10.1016/j.ijfatigue.2007.01.059 SN - 0142-1123 VL - 30 IS - 2 SP - 382 EP - 390 PB - Elsevier CY - Oxford AN - OPUS4-17535 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hähner, P. A1 - Rinaldi, C. A1 - Bicego, V. A1 - Affeldt, E. E. A1 - Brendel, T. A1 - Andersson, H. A1 - Beck, T. A1 - Klingelhöffer, Hellmuth A1 - Kühn, Hans-Joachim A1 - Köster, A. A1 - Loveday, M. A1 - Marchionni, M. A1 - Rae, C. T1 - Research and development into a European code-of-practice for strain-controlled thermo-mechanical fatigue testing N2 - Thermo-mechanical fatigue (TMF) testing plays an increasingly important role in the design, the reliability assessment and the lifecycle management of safety critical components used, for instance, for power generation, in the process industry and in aeronautical and automotive applications, with a view to increasing the fuel efficiency, safety and service intervals, while reducing production (and material) costs. In a European Commission funded research project (acronym: TMF-Standard) of the 5th Framework Programme, 20 European laboratories have undertaken a joint research effort to establish a validated code-of-practice (CoP) for strain-controlled TMF testing. Starting from a survey of the testing protocols and procedures previously used by the partners, a comprehensive pre-normative research activity into various issues has been completed, addressing the dynamic temperature control, the effects of deviations in nominal temperatures and phase angles, the influences of temperature gradients, as well as the practicalities of test interruption and restart procedures. Meaningful allowable tolerances for the various test parameters were identified and practical recommendations as to the test techniques were formulated. From this a preliminary CoP was compiled and used to guide an extensive round robin exercise among the project partners. From the statistical analysis of that exercise, a validated CoP was derived dealing with strain-controlled constant amplitude TMF of nominally homogeneous metallic materials subjected to spatially uniform temperature fields and uniaxial mechanical loading. It is intended to give advice and guidance on the appropriate test setup, testing procedures and the analysis of results, in particular for newcomers in the field of strain-controlled TMF. This paper highlights some of the results of the TMF-Standard project. Moreover, commonalities and differences of the present CoP with respect to the standard documents for strain-controlled TMF, which have been developed at ISO and ASTM levels, are presented in this paper. KW - Thermo-mechanical fatigue KW - Ni-base superalloy KW - Standardisation KW - Test methods PY - 2008 DO - https://doi.org/10.1016/j.ijfatigue.2007.01.052 SN - 0142-1123 VL - 30 IS - 2 SP - 372 EP - 381 PB - Elsevier CY - Oxford AN - OPUS4-17536 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Brookes, Stephen-Peter A1 - Kühn, Hans-Joachim A1 - Skrotzki, Birgit A1 - Klingelhöffer, Hellmuth A1 - Sievert, Rainer A1 - Pfetzing, J. A1 - Peter, D. A1 - Eggeler, G. ED - Kim, Young-Won ED - David Morris, ED - Rui Yang, ED - Christoph Leyens, T1 - Axial-torsional thermo-mechanical fatigue of Ti-45 Al-5Nb-0.2B-0.2C T2 - TMS 2008 Annual Meeting & Exhibition, "Structural Aluminides for Elevated Temperatures - Gamma Titanium and Other Metallic Aluminides" CY - New Orleans, Louisiana, USA DA - 2008-03-09 KW - Titanium Aluminide KW - Thermo-mechanical Fatigue KW - Axial-torsional Loading PY - 2008 SN - 978-0-87339-7209 SP - 103 EP - 109 PB - TMS CY - Warrendale, Pa AN - OPUS4-17904 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schumacher, G. A1 - Darowski, N. A1 - Zizak, I. A1 - Klingelhöffer, Hellmuth A1 - Neumann, W. T1 - Two-stage relaxation of damage structure in strongly creep-deformed single crystal superalloy SC16 measured by means of X-ray diffraction KW - Superalloys KW - SC16 KW - Creep-deformation KW - Relaxation KW - X-ray diffraction PY - 2009 DO - https://doi.org/10.1016/j.scriptamat.2008.09.009 SN - 1359-6462 SN - 1872-8456 VL - 60 IS - 2 SP - 88 EP - 91 PB - Elsevier CY - Oxford AN - OPUS4-18304 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klingelhöffer, Hellmuth A1 - Gründer, Klaus-Peter T1 - Sichere und zuverlässige Anwendung von Werkstoffen - Optische Verfahren zur Untersuchung von Nickel-Basis-Legierungen T2 - Materials Week 2002, Materialica CY - Munich, Germany DA - 2002-09-30 PY - 2002 AN - OPUS4-6129 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Klingelhöffer, Hellmuth A1 - Link, T. A1 - Epishin, Alexander A1 - Fedelich, Bernard A1 - Brückner, Udo A1 - Portella, Pedro Dolabella T1 - Microstructural degredation of CMSX-4 unter creep conditions T2 - Euromat 2007 CY - Nuremberg, Germany DA - 2007-09-10 PY - 2007 AN - OPUS4-15992 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -