TY - JOUR A1 - Ramanathan, Thillaiyan A1 - Schulz, Eckhard A1 - Subramanian, K. T1 - Determination of energy release rate in carbon fiber - Thermoplastic composites and comparison of crack propagation in amorphous and crystalline interface by single fiber pullout test N2 - The fracture toughness in the fiber-matrix composite by means of the single fiber pull-out test can be achievable, if it is possible to measure the compliance of partial debonded fiber, which necessitates a stable crack propagation and the determination of the corresponding crack length. A combination of high stiff test equipment and a simultaneous monitoring of the photo-elastic pattern of the embedded fibers with the help of polarization microscope enables to measure crack length and determination of Gc [Hampe, A and Marotzke, C. (1997). The Energy Release Rate of the Fiber/Polymer Matrix Interface: Measurement and Theoretical Analysis, J. Reinf. Plast. and Compo., 16: 341-352.]. This method is well-known for glass fiber-amorphous polymer composite. In this investigation, we tried to implement the same technique to C-fiber with amorphous and semi-crystalline polymer composites. The energy release rate (ERR) of the fiber-matrix interface was evaluated for the carbon fiber-reinforced in polycarbonate (PC) by interfacial crack propagation arising in the single fiber pullout test. Further, the crack propagation at the fiber-matrix interface with different matrix morphology was discussed with the use of photo-elastic pattern observed with the aid of polarization microscope. KW - Micromechanics KW - Carbon Fibers KW - Thermoplastic polymers KW - Fracture toughness PY - 2004 DO - https://doi.org/10.1177/0731684404039788 SN - 0731-6844 SN - 1530-7964 VL - 23 IS - 15 SP - 1639 EP - 1650 PB - Technomic Publ. Co. CY - Westport, Conn. AN - OPUS4-4486 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schulz, Eckhard A1 - Schulte, K. T1 - Fachausschuss "Gefüge und Eigenschaften von Polymerwerkstoffen" N2 - Die in zunehmenden Maße Mitte der 80er Jahre einsetzende Substitution von metallischen Materialien z. B. durch hochleistungsfähige polymere Werkstoffe und Verbundwerkstoffe wurde u. a. von der DGM zum Anlass genommen, ihre zukünftigen Aufgaben neu zu definieren und gleichzeitig mit der Gründung des Fachausschusses "Gefüge und Eigenschaften von Polymerwerkstoffen" dieser neuen Entwicklung in der Materialkunde auf dem Gebiet der Kunststoffe und ihrer Anwendungen Rechnung zu tragen. KW - Aufgaben KW - Ziele PY - 2004 DO - https://doi.org/10.1515/ijmr-2004-0141 SN - 0044-3093 VL - 95 IS - 9 (85 Jahre DGM) SP - 742 EP - 743 PB - Hanser CY - München AN - OPUS4-5988 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marieta, C. A1 - Schulz, Eckhard A1 - Mondragon, I. T1 - Characterization of interfacial behaviour in carbon-fibre/cyanate composites N2 - In this study an attempt is made to investigate the influence of surface treatments such as oxidation and sizing on a high-strength carbon fibre in respect of interfacial adhesion in composite materials with a cyanate matrix. For analysing the fibre/resin interfacial adhesion the single-fibre pull-out technique has been used. The interfacial shear strengths obtained by this technique have been compared with results of interlaminar shear strength measurements corresponding to woven composite plates. In order to clarify the nature of this interfacial adhesion, both morphological (by atomic force microscopy, AFM) and chemical characterisation (by Fourier transform infrared, FTIR), have also been carried out. PY - 2002 DO - https://doi.org/10.1016/S0266-3538(01)00215-9 SN - 0266-3538 VL - 62 IS - 2 SP - 299 EP - 309 PB - Elsevier CY - Barking AN - OPUS4-6845 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bismarck, A. A1 - Menner, A. A1 - Kumru, M.E. A1 - Sezai Sarac, A. A1 - Bistritz, Martina A1 - Schulz, Eckhard T1 - Poly(carbazole-co-acrylamide) electrocoated carbon fibers and their adhesion behaviour to an epoxy resin matrix N2 - The surface properties of original high strength and preoxidized high modulus carbon fibers were altered by electrocopolymerizing acryl amide and carbazole and therefore depositing a copolymer coating onto the fibers. Scanning electron microscopy and zeta-potential measurements confirmed the presence of a rough but dense and continuous electrocoating with a basic surface character. Therefore, lsquogoodrsquo adhesion behavior between the electrocoated carbon fibers and an epoxy resin matrix should be expected. The interfacial adhesion was measured using the single fiber pull-out and single fiber indentation test. It was shown that only lsquointermediatersquo adhesion was present between the carbon fibers and the electrocoating, but superior adhesion between the coating and epoxy resin exists. The single fiber model composites always failed at the fiber/electrocoating interface. However, as shown by using the indentation test, the interfacial adhesion between fibers and electrocoating can be significantly improved if preoxidized fibers are used as substrate for electropolymerization. A very high tensile strength for the electrocoating can be expected as derived from the single fiber pull-out tests. PY - 2002 DO - https://doi.org/10.1023/A:1013749019958 SN - 0022-2461 SN - 1573-4803 VL - 37 IS - 3 SP - 461 EP - 471 PB - Springer Science + Business Media B.V. CY - Norwell, Mass. AN - OPUS4-6844 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meretz, S. A1 - Auersch, W. A1 - Marotzke, Christian A1 - Schulz, Eckhard A1 - Hampe, Andreas T1 - Investigation of Morphology-dependent Fracture Behaviour with the Single-fibre Pull-out Test PY - 1993 SN - 0266-3538 VL - 48 SP - 285 EP - 290 PB - Elsevier CY - Barking AN - OPUS4-6821 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bismarck, A. A1 - Lee, A.F. A1 - Sarac, A.S. A1 - Schulz, Eckhard A1 - Wilson, K. T1 - Electrocoating of carbon fibres: A route for interface control in carbon fibre reinforced poly methylmethacrylate? N2 - A simple method of creating defined PMMA and poly (MMA-co-Cz) electrocoatings on carbon fibres is described. The electrodeposition of poly methylmethacrylate (PMMA) onto unsized, unmodified carbon fibres was performed by simple constant current electrolyses of methylmethacrylate (MMA) monomer in dimethylformamide (DMF) solutions and the ‘pure’ liquid monomer using sodium nitrate and lithium perchlorate as supporting electrolytes. The presence of polymeric coatings successfully attached to the carbon fibres was verified by scanning electron microscopy and photoelectron spectroscopy (XPS). Performing the electrolysis in dilute MMA in DMF solutions ([MMA] < 5 M) results in the deposition of powder-like polymer on the carbon fibre electrodes. Increasing the MMA concentration in the DMF solution results in a homogeneous PMMA coating of the carbon fibres. The degree of grafting or coating increases with increasing MMA concentration, except when pure MMA is used without solvent. The adhesive strength between the electrocoated carbon fibres and a PMMA matrix was determined using the single fibre pull-out test. It was found that the interfacial fracture behaviour of all carbon fibre/PMMA model composites is rather brittle. The adhesion strength between the unmodified carbon fibres and the PMMA matrix was equal to the cohesive strength of the polymer matrix itself. Nevertheless, the electrodeposition of thin and homogeneous PMMA coatings resulted in much improved adhesion strengths. KW - Carbon fibres KW - Coating KW - Interfacial strength KW - Fibre - matrix bond KW - Photoelectron spectroscopy (XPS) PY - 2005 DO - https://doi.org/10.1016/j.compscitech.2005.01.006 SN - 0266-3538 VL - 65 IS - 10 SP - 1564 EP - 1573 PB - Elsevier CY - Barking AN - OPUS4-7540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Marieta, C. A1 - Schulz, Eckhard A1 - Irusta, L. A1 - Gabilondo, N. A1 - Tercjak, A. A1 - Mondragon, I. T1 - Evaluation of fiber surface treatment and toughening of thermoset matrix on the interfacial behaviour of carbon fiber-reinforced cyanate matrix composites N2 - Composites of carbon fiber and cyanate ester matrix have been investigated. The research has been focused on the interfacial behaviour. The influence of carbon fiber surface treatments, sizing and oxidation, and also modification of thermoset matrix by the addition of a thermoplastic, has been analysed. In order to relate the interfacial behaviour with the characteristics of the components, a physico-chemical characterisation of the carbon fibers and of the cyanate ester resins has been carried out. Thereafter, the apparent interfacial shear strength, the interlaminar shear strength and the Mode II delamination fracture toughness, GIIC, have been measured by pull-out test, short beam-shear test, and end-notched flexure test, respectively. For fractographic analysis the surfaces of laminates fractured under Mode II deformation have also been examined by scanning electron microscopy. KW - Carbon fiber composites KW - Cyanate ester KW - Thermoplastic KW - Interfacial bonding KW - Mechanical properties KW - Morphology PY - 2005 DO - https://doi.org/10.1016/j.compscitech.2005.05.008 SN - 0266-3538 VL - 65 IS - 14 SP - 2189 EP - 2197 PB - Elsevier CY - Barking AN - OPUS4-10891 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutzner, Jürgen A1 - Möhrle, Walter A1 - Schulz, Eckhard A1 - Wüstenberg, Hermann T1 - Zonenaufteilung, Empfindlichkeitseinstellung und Prüfkopfhalterung bei der manuellen Ultraschallprüfung mit dem Tandemverfahren PY - 1975 SN - 0025-5300 VL - 17 IS - 7 SP - 246 EP - 250 PB - Carl Hanser Verlag CY - München AN - OPUS4-8318 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kutzner, Jürgen A1 - Möhrle, Walter A1 - Schulz, Eckhard A1 - Wüstenberg, Hermann T1 - Zonenaufteilung, Empfindlichkeitseinstellung und Prüfkopfhalterung bei der manuellen Ultraschallprüfung mit dem Tandemverfahren (Kurzfassung) PY - 1976 SN - 0340-7551 VL - 6 IS - 2 SP - 71 EP - 73 PB - Bundesanstalt für Materialprüfung CY - Berlin AN - OPUS4-8534 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wüstenberg, Hermann A1 - Kutzner, Jürgen A1 - Schulz, Eckhard A1 - Erhard, Anton T1 - Ultraschallanzeigen von Rißkanten T2 - Europäische Tagung für Zerstörungsfreie Materialprüfung CY - Mainz, Deutschland DA - 1978-04-24 PY - 1978 VL - 1 SP - 99 EP - 106 PB - Deutsche Gesellschaft für Zerstörungsfreie Prüfung CY - Berlin AN - OPUS4-8998 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Mundry, Eberhard A1 - Schulz, Eckhard T1 - Improved Techniques for the Ultrasonic Inspection of Welds T2 - 9th World Conference on Nondestructive Testing CY - Melbourne, Australia DA - 1979-11-19 PY - 1979 SP - 1(?) EP - 10(?) CY - Cannes AN - OPUS4-9196 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -