TY - JOUR A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Mc Hugh, Jarlath A1 - Bartusch, Jürgen T1 - Ultrasound on-line cure monitoring for industrial applications N2 - In recent years eure monitoring with ultrasonic methods became more important. An on-line measurement System for industrial applications is presented in this paper. It operates in through-transmission and the measured parameters are the sound velocity and the attenuation of the sound wave. An objective of this paper is to establish the ränge of possible applications for an ultrasonic eure monitoring System. KW - Ultrasonic monitoring KW - Cure process KW - Composite material KW - Process controlling PY - 2000 SN - 0963-6935 PB - Woodhead Publ. CY - Cambridge AN - OPUS4-1061 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stark, Wolfgang A1 - Döring, Joachim A1 - Goering, Harald A1 - Knappe, S. A1 - Mc Hugh, Jarlath A1 - Opfermann, J. T1 - Der RTM-Prozess und die Probleme von Gelierung, Verglasung und Aushärtegrad T2 - 6. Internationale AVK-TV Tagung für Verstärkte Kunststoffe und Duroplastische Formmassen ; 6th International AVK-TV Conference for Reinforced Plastics and Thermoset Moulding Compounds CY - Baden-Baden, Deutschland DA - 2003-10-07 KW - Epxidharz KW - Compositbauteil KW - Vernetzungsreaktion PY - 2003 VL - 6 SP - C14-1-C14-16 PB - AVK-TV CY - Frankfurt am Main AN - OPUS4-3034 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fengler, Petra A1 - Stark, Wolfgang A1 - Döring, Joachim A1 - Mc Hugh, Jarlath T1 - Coupling of hidden ultrasound sensors to a moulding tool N2 - Ultrasound on-line NDT methods have been demonstrated as a useful tool for monitoring the curing reaction of thermosets. In order to achieve this ultrasound sensors are incorporated into compression, injection and RTM (resin transfer) mould. For many commercial products imprints or any surface markings upon the moulded product are undesirable. Due to its physical properties ultrasound has a large advantage over other techniques for similar applications. The sound wave can pass through the wall of the mould and direct contact with the moulded part is not required. In this particular case one fundamental problem is a good coupling of the sensors to the mould wall. Several mediums came into question but because of the high technical (e. g. temperature and long time stability) and practical demands, it was decided that dry (non-fluid) coupling would be the most promising candidate. A handful of coupling foils suitable also at high temperatures and for long time application under industrial conditions were tested and are presented in this paper. KW - Sensors KW - Ultrasound KW - Mould wall coupling KW - Thermoset manufacturing PY - 2004 UR - http://www.ndt.net/article/v09n03/stark/stark.htm SN - 1435-4934 VL - 9 IS - 3 SP - 1 EP - 10 PB - NDT.net CY - Kirchwald AN - OPUS4-3316 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Bartusch, Jürgen A1 - Mc Hugh, Jarlath T1 - Contribution to ultrasound cure control for composite manufacturing N2 - The curing conditions play an important role in the quality assurance of composite products. Especially as composite materials are widely used in high tech areas so that they are required to fulfil high quality Standards. Some problems which occur during curing, for instance undercuring, can hardly be detected using Standard NDT investigations, mainly because they are manifested only at high temperatures, particularly close to glass-rubber-transition. On-line eure monitoring has the outstanding advantage that it can monitor the material parameters even at the highest temperatures possible. In recent years eure monitoring with ultrasonic methods has become more populär. In comparison to dielectric methods mechanical parameters are measured directly. The quantities to be measured are the velocity and the attenuation of the sound wave. On this basis the storage and loss modulus can be calculated. Depending on the form of excitation with longitudinal or transversal waves these moduli are referred to as long wave or shear modulus. Well developed Computer based technology and sensor materials are available in the non-destructive testing (NDT) market. The measuring equipment employed a commercial NDT System, which worked computer-aided. With a special Software the demands of automatic Operation under industrial conditions was accomplished. This measurement equipment was tested on composites. Its structure, performance and some practical results will be presented in the following paper. T2 - 15th World Conference on Non-Destructive Testing (WCNDT) CY - Roma, Italy DA - 15.10.2000 PY - 2000 UR - http://www.ndt.net/article/wcndt00/papers/idn482/idn482.htm SN - 1435-4934 VL - 5 IS - 11 PB - NDT.net CY - Kirchwald AN - OPUS4-2136 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Mc Hugh, Jarlath A1 - Stark, Wolfgang A1 - Kürten, C. T1 - Mit Ultraschall sieht man mehr - Kontrolle von Werkzeugfüllung und Vernetzungsreaktion beim Harzinjektionsverfahren RTM T2 - Poster-Ausstellung "Sensorik in der BAM" CY - Berlin, BAM, Deutschland DA - 2002-10-01 PY - 2002 SP - 1(?) AN - OPUS4-2114 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Mc Hugh, Jarlath A1 - Bartusch, Jürgen A1 - Fengler, Petra T1 - Rheologische und akustische Bestimmung der Fließ-Härtungseigenschaften von Injektionsharzen N2 - Zusammenfassung Der Ausgangspunkt für diese Arbeiten ist eine in [1] beschriebene Ultraschall-(US)-Sensorik zur Aushärtungskontrolle. Sie wurde für rieselfähige Formmassen entwickelt [2,3]. Darauf aufbauend ist es das Ziel der vorliegenden Arbeit, die Voraussetzungen für den Einsatz dieser Sensorik beim Harzinjektionsverfahren zu schaffen und ihre Kalibrierung durch rheologische und DSC-Messungen zu ermöglichen. Der erste Teil des Beitrages beschäftigt sich mit dem technologischen Ablauf des Harzinjektionsverfahren und den Einsatzmöglichkeiten der US-Sensorik bei dieser Technologie. Ergebnisse von Schallgeschwindigkeits- und Dämpfungsmessungen für EP-Harze werden vorgestellt. Im zweiten Teil wird auf das Kalibrieren der US-Sensorik für den Verarbeiter eingegangen. Es kann mittels der bisherigen Prozessführung oder durch Vergleich mit den Ergebnissen anderer Mess-Verfahren wie Rheometer- oder Differential-Scanning-Calerometry-(DSC)-Messungen erfolgen. T2 - Jahrestagung Zerstörungsfreie Materialprüfung 2002 CY - Weimar, Deutschland DA - 2002-05-06 KW - Ultraschall KW - Harzinjektionsverfahren KW - RTM KW - Prozesskontrolle KW - Aushärtung PY - 2002 UR - http://www.ndt.net/article/dgzfp02/papers/v51/v51.htm SN - 3-931381-39-0 N1 - Serientitel: Berichtsband / Deutsche Gesellschaft für zerstörungsfreie Prüfung e. V. – Series title: Berichtsband / Deutsche Gesellschaft für zerstörungsfreie Prüfung e. V. IS - 80-CD PB - DGZfP CY - Berlin AN - OPUS4-1913 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mc Hugh, Jarlath A1 - Stark, Wolfgang A1 - Döring, Joachim ED - Green, R. E. ED - Djordjevic, B. B. ED - Hentschel, M. P. T1 - Evaluation of the cure behaviour of epoxy resin using rheometric and ultrasonic techniques T2 - 11th International Symposium on Nondestructive Characterization of Materials CY - Berlin, Germany DA - 2002-06-24 PY - 2003 SN - 3-540-40154-7 SP - 651 EP - 658 PB - Springer CY - Berlin AN - OPUS4-2772 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mc Hugh, Jarlath A1 - Döring, Joachim A1 - Erhard, Anton A1 - Stark, Wolfgang A1 - Raab, S. T1 - Einfluss hoher Temperaturen und Drücke auf die Ultraschalleigenschaften eines Komposit-Prüfkopfes T2 - Jahrestagung Zerstörungsfreie Materialprüfung 2004 CY - Salzburg, Österreich DA - 2004-05-17 PY - 2004 UR - http://www.ndt.net/article/dgzfp04/papers/p12/p12.htm SN - 3-931381-55-2 SP - 1 EP - 7(?) PB - DGZfP CY - Berlin AN - OPUS4-5214 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Mc Hugh, Jarlath A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Erhard, Anton T1 - Characterisation of epoxy materials used in the development of ultrasound arrays T2 - 16th World Conference on Nondestructive Testing CY - Montreal, Canada DA - 2004-08-30 PY - 2004 UR - http://www.ndt.net/article/wcndt2004/pdf/materials_characterization/616_mchugh.pdf SP - 8 pages PB - International Committee for Non-Destructive Testing CY - Montreal AN - OPUS4-5215 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Bartusch, Jürgen A1 - Mc Hugh, Jarlath A1 - Simon, W. T1 - Ultraschall-Prozesskontrolle mechanischer Parameter von aushärtenden Polymeren - Inline-Sensorik für die Herstellung von Kunststoffkomponenten KW - Aushärtung KW - Ultraschall KW - Sensoren KW - Materialparameter PY - 2007 SN - 0025-5300 VL - 49 IS - 5 SP - 238 EP - 242 PB - Hanser CY - München AN - OPUS4-14976 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mc Hugh, Jarlath A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Guey, J. L. T1 - Relationship between the Mechanical and Ultrasound Properties of Polymer Materials T2 - 9th European Conference on NDT CY - Berlin, Germany DA - 2006-09-25 KW - Ultrasound KW - DMA KW - Epoxy KW - Modulus KW - tan delta KW - High temperature PY - 2006 SN - 3-931381-86-2 SP - 1(?) EP - 9(?) PB - European Federation for Non-Destructive Testing CY - Berlin AN - OPUS4-14065 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mc Hugh, Jarlath A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Stark, Wolfgang T1 - Making Cure Visible T2 - Aerospace Testing Expo 2005 - Europe, April 5-7, 2005, Hamburg CY - Hamburg, Deutschland DA - 2005-04-05 PY - 2005 SP - 4 pages PB - UKIP Media & Events CY - Dorking AN - OPUS4-7379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stark, Wolfgang A1 - Bartusch, Jürgen A1 - Döring, Joachim A1 - Mc Hugh, Jarlath T1 - Making cure visible: monitoring the crosslinking process using integrated ultrasound sensors N2 - A special ultrasonic measuring system was developed to monitor the cross-linking process, enabling interaction with the manufacturing process in order to optimise part quality and reduce cycle times. KW - Thermoset KW - Ultrasound sensors KW - Mould KW - Rtm KW - Gelation KW - Vitrification PY - 2008 SN - 1639-965X IS - 38 SP - 64 EP - 66 PB - JEC CY - Paris AN - OPUS4-18610 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Döring, Joachim A1 - Stark, Wolfgang A1 - Mc Hugh, Jarlath A1 - Bartusch, Jürgen T1 - Erfassung des Fließ-Härtungs-Verhaltens von Duromeren mit Ultraschall N2 - Das Fließ-Härtungs-Verhalten von Duroplastformmassen wird gegenwärtig nur unvollständig durch empirische Größen beschrieben. Diese ungenauen und unsicheren Angaben können zu Schwierigkeiten bei der optimalen Einstellung der Fertigungsmaschinen des Verarbeiters führen. Insbesondere Veränderungen der Formmasseeigenschaften während des Transportes und der Lagerung stören die Produktion. Das vorgestellte Messverfahren mit Ultraschall-sensoren ermöglicht die schnelle und vollständige Erfassung des Fließ-Härtungs-Verhaltens, auch während des technologischen Prozesses. Experimentelle Ergebnisse zu Alterungs-erscheinungen dieser Formmassen illustrieren den Nutzen des Verfahrens für Formmasse-produzenten und -verarbeiter. T2 - DGZfP-Jahrestagung 1999 CY - Celle, Deutschland DA - 1999-05-10 PY - 1999 SN - 3-931381-27-7 IS - DGZfP-BB 68 SP - 221 EP - 228 AN - OPUS4-22937 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Mc Hugh, Jarlath A1 - Fideu, P. A1 - Herrmann, A. A1 - Stark, Wolfgang T1 - Determination and review of specific heat capacity measurements during isothermal cure of an epoxy using TM-DSC and standard DSC techniques N2 - The technique normally used to measure Cp during isothermal cure is Temperature Modulated - Dynamic Scanning Calorimetry TM-DSC. It is however not standardised, experimentally complicated and quite time intensive. As will be shown, Cp may also be estimated during isothermal cure just from using dynamic heating experiments on a fully cured sample. Such values are often sufficient for isothermal heat transfer models that otherwise employ a constant Cp value obtained from the fully cured epoxy. Secondly, the results from dynamic heating experiments provide a quick means, in comparison to isothermal TMDSC measurements, of estimating Cp variation during cure as well as providing a good estimate value for Cp towards the end of isothermal cure. As will be shown, such values obtained from a standardised measurement procedure are very helpful in setting up TMDSC experiments that are more sensitive to experimental error influenced by factors such as sample weight and geometry. The DSC results illustrate that the measured heat capacity Cp for a fully cured epoxy over a temperature range are very similar to values for samples partially cured at corresponding isothermal temperatures, under the prerequisite that vitrification takes place. In such cases the primary influence on Cp is specific measurement temperature and not degree of cure. For isothermal cure temperatures investigated between 150 and 200 °C, the total change of Cp during cure is nearly constant and correlates well with values published by authors on other epoxy based systems. Taking Cp variation as constant, it is possible from just dynamic heating experiments on the cured epoxy to estimate Cp for the uncured epoxy system at specific cure temperatures. The next step would be to estimate the full Cp profile during isothermal cure, however, in such cases, the time to vitrification would also be needed as additional information. PY - 2010 U6 - https://doi.org/10.1016/j.polymertesting.2010.04.004 SN - 0142-9418 VL - 29 IS - 6 SP - 759 EP - 765 PB - Elsevier Science CY - Amsterdam [u.a.] AN - OPUS4-21916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stark, Wolfgang A1 - Jaunich, Matthias A1 - Mc Hugh, Jarlath T1 - Dynamic mechanical analysis (DMA) of epoxy carbon-fibre prepregs partially cured in a discontinued autoclave analogue process N2 - Epoxy carbon-fibre prepreg, Hexcel Type 6376 HTS, was investigated using Dynamic Mechanical Analysis (DMA). The DMA characteristic parameters are storage modulus E', loss modulus E' and loss factor tanδ. These parameters are ideally suited to observe the vitrification, referred to as glass transition, resulting from the cross-linking reaction. Detection of the cure state may also be achieved by determining the momentary glass transition temperature of partially cured samples. The consequent use of a multi-frequency measuring regime was used to derive the apparent activation energy for the glass transition process. Different temperature programs were also applied to monitor the curing process directly, as well as to investigate the different states of incomplete cure reached in preceding curing steps. The intention was to provide better understanding of the consequences of an interrupted autoclave curing process and to use DMA to detect the cure state achieved. With DMA, the continuation of an incomplete curing process also can be monitored. DMA measurements up to 300 °C showed, furthermore, that the final glass transition temperature was reduced by thermal degradation at high temperatures. KW - Composites KW - Epoxy KW - Cross-linking KW - Prepreg KW - Degree of cure KW - Glass transition PY - 2015 U6 - https://doi.org/10.1016/j.polymertesting.2014.11.004 SN - 0142-9418 VL - 41 SP - 140 EP - 148 PB - Elsevier Science CY - Amsterdam [u.a.] AN - OPUS4-32325 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -