TY - CHAP A1 - Hartmann, Jürgen A1 - Machin, Graham A1 - Yamada, Y. A1 - Lowe, D. A1 - Sasajima, N. A1 - Anhalt, Klaus A1 - Goebel, R. A1 - McEvoy, H.C. A1 - Bloembergen, P. ED - Zvizdic, D. T1 - A comparison of high temperature fixed-points of Pt-C and Re-C constructed by BIPM, NMIJ and NPL BT - Proc. 9th Int. Symp. on Temperature and Thermal Measurements in Industry and Science T2 - Proceedings of Tempmeko 2004 Y1 - 2005 SP - 1049 EP - 1056 PB - LPM/FSB CY - Zagrep ER - TY - JOUR A1 - Hartmann, Jürgen T1 - A study on the feasibility of measuring the emissivity with the laser-flash method JF - International Journal of Thermophysics N2 - The laser-flash method is a fast, widely used and well established technique to measure the thermal diffusivity. Since its introduction in the 1960s, it was proposed to expand this technique to the measurement of heat capacity and emissivity. Currently, the measurement of spectral emissivity at high temperatures is connected with relatively large uncertainties, although the spectral emissivity is an essential parameter for applications, e.g., in the lamp industry and fusion research. In this work, a theoretical study is presented on the possibility of emissivity measurements using the laser-flash method. Two mathematical approaches are discussed which solve the problem, that a measured temperature rise—necessary to calculate the emissivity—itself depends on the emissivity. It is shown that both methods have a negligible arithmetic error, making them applicable to be used in future work. Y1 - 2010 UR - https://link.springer.com/content/pdf/10.1007/s10765-010-0767-z.pdf VL - 31 IS - 4-5 SP - 998 EP - 1010 ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Thermodynamic temperature measurements of the melting curves of RE-C, TIC-C And ZRC-C eutectic irradiance mode fixed-point cells T2 - Proceedings TEMPMEKO 2004 N2 - The thermodynamic temperatures of the phase transition of Re-C, TiC-C, and ZrC-C eutectic fixed-point cells have been measured for the first time using different filter radiometers in irradiance mode. The spectral responsivity of these filter radiometers was measured traceable to the primary detector standard of the PTB, a laser based cryogenic radiometer. The relative extended uncertainties of the spectral responsivities of the filter radiometers in the irradiance mode were in the range from 5· 10-4 up to 2.5· 10-3. The measurements have been performed at the high temperature calibration facilities of the VNIIOFI and the PTB with eutectic fixed-point cells manufactured by VNIIOFI. Y1 - 2004 UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.454.3165&rep=rep1&type=pdf SP - 189 EP - 194 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - A comparison of the blackbody cavities for infrared ear thermometers of NMIJ, NPL, and PTB JF - AIST Bulletin of Metrology N2 - A comparison of the NMIJ, the NPL, and the PTB blackbody cavities for infrared ear thermometers has been performed for the first time. The NMIJ and the PTB have transported their standard blackbodies to the NPL and radiance temperatures of the blackbodies of the institutes have been directly compared simultaneously using high-resolution infrared ear thermometers as comparators. The results of the comparison show that radiance temperatures realized by the NMIJ, the NPL, and the PTB cavities agree within +/-0.01 deg C, well within their uncertainty levels of around 0.04 deg C in the temperature range from 35 deg C to 42 deg C. Y1 - 2007 VL - 5 IS - 4 SP - 251 EP - 256 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Friedrich, R. A1 - Schiller, S. A1 - Fischer, J. ED - Fellmuth, B. ED - Seidel, J. ED - Scholze, G. T1 - Non-isothermal temperature distribution and resulting emissivity corrections for the high temperature blackbody BB3200 T2 - Proc. 8th International Symposium on Temperature and Thermal Measurements in Industry and Science - Proceedings of Tempmeko 2001 Y1 - 2002 SP - 227 EP - 232 PB - VDI Verlag CY - Berlin ER - TY - CHAP A1 - Hartmann, Jürgen T1 - A comparison of Co-C, Pd-C, Pt-C, Ru-C and Re-C eutectic fixed points independently manufactured by three different institutes T2 - Proc. Newrad (Davos, Switzerland) N2 - In order to assess the performance and capability as well as the reproducibility of cell production five different Metal-carbon (MC) eutectic cells from three institutes were measured by radiation thermometry at PTB. The reproducibility of the melting temperature approached the requirements set by CCT/CCPR but significant differences were seen between different manufactures. Y1 - 2005 UR - https://www.academia.edu/download/41206514/A_comparison_of_CoC_PdC_PtC_RuC_and_ReC_20160114-3055-1lybi4p.pdf20160115-19908-1rtghdd.pdf SP - 289 EP - 290 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Sadli, M. A1 - Machin, G. A1 - Morice, R. ED - Fellmuth, B. ED - Seidel, J. ED - Scholze, G. T1 - Realisation and comparison of metal-carbon eutectic points for radiation thermometry applications and W-Re thermocouple calibration T2 - Proc. 8th Int. Symp. on Temperature and Thermal Measurements in Industry and Science - Proceedings of Tempmeko 2001 N2 - For the sake of ensuring improved accuracy and traceability for temperature measurements above the copper point (1084 OC), four laboratories are joining their efforts in developing high-temperature fixed points based on eutectic transitions of metal-carbon mixtures [1]. These phase transitions, on the basis of radiation thermometry results presented thus far [2, 3], encouraged the participants to work towards two eventual applications: hightemperature fixed—point calibration sources for radiation thermometry, and fixed points for the calibration of contact thermometers, including Pt/Pd, Pt/Rh and W/Re thermocouples. Here will be given the up-to—date works accomplished within or in relation with this project in the participating laboratories. The perspectives of this work are wide and should allow the usage of such fixed points at temperatures ranging from 1150 C to 2700 C. The remaining uncertainty concerns the … Y1 - 2002 UR - https://www.researchgate.net/profile/Graham_Machin/publication/259712992_Realisation_and_comparison_of_metal-carbon_eutectic_points_for_radiation_thermometry_applications_and_W-Re_thermocouple_calibration/links/02e7e52d6c8d4c143c000000.pdf SP - 507 EP - 512 PB - VDI Verlag CY - Berlin ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Measurement of T-T90 down to zinc point temperatures with absolute filter radiometry T2 - Proc. of TEMPMEKO Y1 - 2001 SP - 377 EP - 382 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Taubert, Dieter Richard A1 - Fischer, Joachim ED - Dubbeldam, J.F. ED - de Groot, M.J. T1 - Characterization of the double-heatpipe blackbody LABB for use at temperatures below 500 C T2 - Proceedings of TEMPMEKO (99) N2 - The large area double-heatpipe blackbody (LABB) used for comparing thermodynamic temperatures with the International Temperature Scale of 1990 (ITS-90) at temperatures higher than 600 C is based on two sodium heat pipes. The lowest temperature at which the sodium heat pipes work properly is strongly correlated to the onset of sodium evaporation. This is expected for temperatures well above 500 C. Planning to use the LABB for extending the comparison of thermodynamic temperatures with the ITS-90 to temperatures as low as possible, we measured the isothermal behaviour of the blackbody cavity starting at heatpipe temperatures of 400 C. The temperature of the cylindrical part of the cavity was measured with a standard platinum resistance thermometer (SPRT) sensing the bottom of the cavity and up to three quarter of the cylindrical part of the cavity. The obtained temperature profiles are well explained assuming the occurrence of two superimposing effects: a real nonisothermal behaviour of the LABB for temperatures below 500 C and a cooling of the SPRT caused by radiation loss through the aperture of the cavity. Applying a Monte-Carlo simulation we calculated the emissivity of the LABB at different heatpipe temperatures below 600 C using the obtained non-isothermal temperature distribution at the cylindrical walls. It was found that even at temperatures as low as 415 C the accuracy of the LABB is sufficient for comparison of thermodynamic temperatures and the ITS-90. Y1 - 1999 UR - https://www.researchgate.net/profile/Juergen_Hartmann3/publication/279059568_Characterization_of_a_double-heatpipe_blackbody_LABB_for_use_at_temperatures_below_500_c/links/5589455b08ae9076016e9a81/Characterization-of-a-double-heatpipe-blackbody-LABB-for-use-at-temperatures-below-500-c.pdf SP - 511 EP - 516 PB - IMEKO CY - Delft ER - TY - JOUR A1 - Hartmann, Jürgen T1 - Traceable Radiometric Calibration of Semiconductor Detectors and their Application for Thermodynamic Temperature Measurement JF - Journal of Metrology Society of India N2 - The non-contact measurement of temperature by using the emitted thermal radiation has been an innovative field of measurement science and fundamental physics for more than a hundred years. It saw the first highlight in Gustav Kirchhoff’s principle of a blackbody with ideal emission characteristics and culminated in Max Planck’s formulation of the law of thermal radiation, the so-called Planck’s law, forming the foundation of quantum physics. A boost in accuracy was the development of semiconductor detectors and the cryogenic electrical substitution radiometer in the late 1970s. Semiconductor detectors, namely photodiodes, deliver an electrical current proportional to the absorbed optical radiation. Due to the measurements of thermal radiation over a wide range of temperature and wavelength, thermodynamic temperature measurements with radiometric methods have set benchmarks to all, the … Y1 - 2010 UR - http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.452.930&rep=rep1&type=pdf VL - 25 IS - 1 SP - 3 EP - 10 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Sakuma, F. A1 - Ma, L. T1 - Intercomparison of Radiation Temperature Scales between PTB and NMIJ from 1000-degree Celsius to 2500-degree Celsius T2 - SICE Annual Conference Program and Abstracts SICE Annual Conference 2002 N2 - The intercomparison of radiation temperature scales between PTB and NMIJ was carried out in September 2001. PTB sent their radiation thermometer LP3 to Japan and NMIJ made the comparison between the LP3 and NMIJ’s Topcon radiation thermometers with a comparison blackbody from 1000 C to 2500 C. Both scales agreed within±0.8 C in the whole range. Y1 - 2002 UR - https://doi.org/10.11499/sicep.2002.0.13.0 SP - 13 EP - 13 PB - The Society of Instrument and Control Engineers ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Thermal characterisation of diamond T2 - Properties, Growth and Applications of Diamond N2 - Thermal characterisation of diamond is one of the key issues in assessing material quality since thermal parameters are strongly related to other features like isotopic constitution, defect content and microstructure (see Datareview A 1.5). Hence, the macroscopic thermal conductivity can often be taken as a figure-of-merit for diamond quality relevant for industrial applications. Determining thermal conductivity of diamond materials does not require, in principle, techniques other than those used for thermal assessment of more common materials and the standard methods as well as their application to diamond have been described in detail in rather complete review articles [1, 2]. Recent advancements in methodology have mainly been focused on thermal microscopy for measuring conductivity in extremely small volumes and finally single grains of polycrystalline material [3] and to quantitatively determine resistances across thermal barriers related to grain boundaries in thin films [4]. In this survey we summarise the main features of the standard techniques and briefly review the technology of quantitative thermal microscopy. It is difficult to precisely control and measure heat flow and radiation and, hence, thermal measurements generally yield only a rather limited precision; this fully applies also to measurements on diamond materials. An accuracy of a few per cent has to be regarded as excellent while the precision of most measurements is at a 5 to 10% level or below. As demonstrated by a recent round robin test [5], this especially applies to the characterisation of polycrystalline thin films where measurements may be strongly affected by the … Y1 - 2001 PB - Institute of Engineering & Technology ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Ricolfi, T. A1 - Batuello, M. A1 - Bosma, R. A1 - van der Ham, E. A1 - Fischer, J. ED - Fellmuth, B. ED - Seidel, J. ED - Scholze, G. T1 - Comparison of local realizations of the ITS-90 between 920° C and 1590° C at 950 nm using vacuum tungsten strip lamps as transfer standards T2 - Proc. of TEMPMEKO (2001) Y1 - 2002 SP - 839 EP - 844 PB - VDI Verlag CY - Berlin ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Breuer, J. A1 - Johannsen, U. A1 - Rabus, H. A1 - Werner, L. T1 - PTB detector calibration capabilities for optical radiometry T2 - Sensor 2001 Proceedings N2 - In the first part of this paper we give a brief survey of the approaches taken to achieve these rather challenging goals. Then we will focus on some aspects of transfer detector standards that have to be taken into account if the highest possible accuracy is to be reached. The final section of the paper deals with a new and very promising method for the dissemination of the spectral responsivity of semiconductor photodiodes. Y1 - 2001 SP - 227 EP - 232 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Gutschwager, B. A1 - Fischer, J. T1 - Calibration facility for infrared thermography systems at PTB T2 - Sensor 2001 Proceedings N2 - Section 2 of the present paper introduces the two calibration facilities, presents the applied blackbody radiation sources with the achievable uncertainties, the collimator optics, and the climate box. A short introduction of the experimental techniques used and presentation of some experimental results for different camera systems follows in Section 3. A final conclusion is given in Section 4. Y1 - 2001 SP - 233 EP - 238 ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Complete characterization of local thermal transfer in high quality CVD diamond T2 - AIP Conference Proceedings (463) N2 - Room temperature microscopic thermal transfer in a high quality chemical vapor deposited diamond sample is completely characterized with micrometer resolution. A thermoreflectance microscope measures thermal conductivity and its slight variations inside a grain. Measurements reveal an inhomogeneous conductivity distribution with highest values close to that of natural IIa diamond. Using the same microscope, frequency dependent investigations of thermal barriers located between diamond grains are performed. Thermal resistance is found to vary between 10−9 and 10−8 m2K/W. Frequency dependent measurements sensitive to three-dimensional heat flow and averaging over a variable number of grains yield an enormous decrease of thermal conductivity with decreasing modulation frequency. Taking the average of thermal conductivity inside the grains and an average value for the barrier height together … Y1 - 1999 SP - 295 EP - 299 ER - TY - JOUR A1 - Hartmann, Jürgen A1 - Reichling, M. T1 - Photothermische Mikroskopie BT - Berührungslose Temperaturmessung mit höchster räumlicher Auflösung Y1 - 1998 SP - 221 EP - 226 PB - VDI-Bericht 1379 ER - TY - JOUR A1 - Hartmann, Jürgen T1 - Condensed matter: structural, mechanical, and thermal properties BT - local variation of room-temperature thermal conductivity in high-quality polycrystalline diamond JF - Applied Physics Letters Y1 - 1998 VL - 73 IS - 6 SP - 756 EP - 758 ER - TY - CHAP A1 - Hartmann, Jürgen T1 - Improvement of the active layers of a MIS-structure semiconductor gas sensor for HF and F Y1 - 1995 ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Manara, Jochen A1 - Arduini, Mariacarla T1 - A Novel Approach for Non-Destructive Testing of the Adhesion of Thermal Barrier Coatings N2 - The operation temperatures of gas turbine engines have been increased significantly to optimize their efficiency factor. To protect the metallic blades from these high temperatures, thermal barrier coatings (TBCs) are applied onto the turbine blades. These layers must have a good adhesion to the supporting turbine blade. A poor adhesion may lead to a delamination of the layer during operation and finally to a destruction of the turbine blade and eventually the complete turbine. It is therefore necessary, to check the quality of the layer adhesion regularly during service or preferably during operation. Approaches for non-contact and nondestructive techniques by using optical or infrared radiation are not sophisticated up to now. Hence in this paper a new attempt to improve these optical or infrared-optical methods is described. The presented idea relies on the application of different wavelengths for the used measurement system. Using a short wavelength range, where the TBC is semitransparent, allows the measurement of the temperature of the turbine blade. Using a second, long wavelength range where the TBC is non-transparent, the temperature of the surface of the TBC can be determined. As the thermal contact is usually correlated with the mechanical adhesion such measurements can be a possible tool for nondestructively testing the adhesion of TBCs. Y1 - 2016 UR - https://www.researchgate.net/profile/Juergen_Hartmann3/publication/309291712_A_Novel_Approach_for_Non-Destructive_Testing_of_the_Adhesion_of_Thermal_Barrier_Coatings/links/5ec230b2458515626cb0b295/A-Novel-Approach-for-Non-Destructive-Testing-of-the-Adhesion-of-Thermal-Barrier-Coatings.pdf SP - 12 EP - 13 PB - The Future of Gas Turbine Technology ; 8 th International Gas Turbine Conference CY - Brüssel (Belgien) ER - TY - CHAP A1 - Hartmann, Jürgen A1 - Werner, L. A1 - Fischer, J. A1 - Johannsen, U. T1 - Accurate determination of the spectral responsivity of silicon trap detectors between 238 nm and 1015 nm using a laser-based cryogenic radiometer BT - Newrad’99 Y1 - 1999 CY - Madrid (Spanien) ER -