TY - CONF A1 - Baer, Wolfram A1 - Müller, Karsten A1 - Wossidlo, Peter A1 - Klingbeil, Dietmar T1 - Dynamic fracture toughness behaviour of ductile cast iron with respect to structural integrity assessment N2 - Modern structural integrity assessment procedures in the field of nuclear related technology incorporate fracture mechanical concepts. Therefore, they inevitably require the availability of both, loading parameters as well as material characteristics in terms of fracture mechanical quantities. Especially in case of dynamic loading conditions, the methods for the determination of the loading parameters need further improvement and there is a lack of material characteristics as well. In Germany, ductile cast iron (DCI) is used for heavy-sectioned casks for radioactive materials. New developments in cask design and efforts to extend the application limits require further investigations. The present study is part of an ongoing fracture mechanics research programme of BAM which is focused on the systematic mechanical and fracture mechanical material characterisation of DCI materials under dynamic loading conditions. In this study, results of fracture mechanics investigations on ductile cast iron from an original DCI container with a wide variety of microstructure under dynamic loading conditions in the temperature range from -50 °C to +22 °C are presented. Large scale as well as small scale single edge crack bend specimens SE(B) with thicknesses of 140 mm and 15 mm, respectively were tested. Furthermore, it is reported on the results of a finite element simulation of the dynamic large scale fracture mechanics tests. Strength and deformation characteristics were determined in dynamic tensile tests. They are discussed with respect to the influence of pearlite content and test temperature. The material specific experimental difficulties in the determination of reliable dynamic crack initiation toughness values of DCI are outlined. T2 - 17th International Conference on Structural Mechanics in Reactor Technology ; SMiRT 17 CY - Prague, Czech Republic DA - 2003-08-17 KW - Dynamic fracture toughness KW - Ductile cast iron KW - Structural integrity KW - Component KW - Specimen geometry KW - Testing KW - Loading rate KW - Test temperature KW - Microstructure KW - Graphite morphology KW - Crack initiation toughness KW - Analysis procedure KW - Finite element simulation KW - Fracture mechanics PY - 2003 IS - G04-4 SP - 1 EP - 8 CY - Prague AN - OPUS4-2856 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Müller, Karsten A1 - Wossidlo, Peter A1 - Baer, Wolfram ED - Dlouhý, I. T1 - Fracture toughness behaviour of thick-walled nodular cast iron at elevated loading rates T2 - NATO Final Project Workshop on Fracture Resistance of Steels for Containers of Spent Nuclear Fuel ; NATO Final Project Workshop on Transferability of Fracture Mechanical Data CY - Brno, Czech Republic DA - 2001-11-05 KW - Ductile cast iron KW - Fracture mechanics KW - Specimen size effect KW - Loading rate effect PY - 2002 SN - 1-402-00794-9 SN - 1568-2609 N1 - Serientitel: NATO science series : Series 2, Mathematics, physics and chemistry – Series title: NATO science series : Series 2, Mathematics, physics and chemistry IS - 78 SP - 283 EP - 290 PB - Kluwer Academics Publishers CY - Dordrecht AN - OPUS4-1548 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zencker, Uwe A1 - Müller, Karsten T1 - Modern Safety Assessment of Cubic Cast Iron Containers Under Mechanical Impact N2 - In the present study, ductile cast iron from an original DCI container with a wide variety of microstructure was investigated in order to determine the materials fracture toughness under impact loading conditions. Three-point bending specimens with thickness of 140 mm from a cubic DCI container were investigated at elevated loading rates to provide reliable fracture toughness parameters for the assessment procedures. In contrast to static fracture behaviour, the fracture toughness values of thick-walled DCI at higher loading rates show a remarkable reduction with decreasing temperature up to –50 °C and a significant shift of the transition range. The lower bound fracture toughness value used in the BAM DCI safety concept was confirmed for impact loading conditions by these fracture mechanics tests using large specimens. These measurements are relevant to the licensing tests for storage containers without shock absorbers, especially to the assessment of the dynamic behaviour of crack-like defects inside a cask structure under drop test conditions. Using extensive dynamic numerical analyses it could be shown, that for special crack configurations the dynamic crack tip parameter (KI, or J) may be estimated by static formulae even under mechanical impact. These results of the safety assessment were verified according to the German Konrad repository acceptance criteria by a drop test with a cubic waste container with artificial crack-like defects from 5 m height onto a representative storage facility foundation. T2 - 17th International Conference on Structural Mechanics in Reactor Technology ; SMiRT 17 CY - Prague, Czech Republic DA - 2003-08-17 KW - Ductile cast iron KW - Mechanical impact KW - Dynamic fracture KW - Safety assessment KW - Storage containers PY - 2003 IS - G04-4 SP - 1(?) EP - 8(?) CY - Prague AN - OPUS4-2650 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Karsten A1 - Schriever, Sina A1 - Wossidlo, Peter A1 - Hamann, Andreas A1 - Löwe, Peter T1 - Bruchmechanische Untersuchungen von Gusseisen mit Kugelgraphit bei Stoss- und Schlagbiege-Beanspruchung T2 - 33. Tagung des DVM-Arbeitskreises Bruchvorgänge CY - Paderborn, Deutschland DA - 2001-02-20 KW - Ductile cast iron KW - DCI KW - Dynamic fracture toughness PY - 2001 SN - 0943-3473 N1 - Sprachen: Deutsch/Englisch - Languages: German/English IS - 233 SP - 267 EP - 274 PB - DVM CY - Berlin AN - OPUS4-1088 LA - mul AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -