Analyses of Dynamic Fracture Toughness Data of Ductile Cast Iron based onASME Code Case N-670 and ASTM E 1921

摘要

This paper is on dynamic fracture toughness of ductile cast iron materials (DCI). One major field of application of DCI in Germany is the production of casks for transport and storage of radioactive materials. The improved German safety as-sessment concept [1] for these thick-walled components incorporates a complete fracture mechanical safety assessment which has to cover all possible loading conditions in normal service as well as with (dynamic) accident conditions. Any component failure by brittle or ductile crack initiation has to be excluded in all cases. Nevertheless, a statistically based, detailed data base of reliable dynamic fracture toughness data is required but not yet finally available. This should also take into account systematically influences like microstructure, loading-rate, tem-perature and specimen size. In order to make a step forward in this direction, the present paper is focused on the statistical analysis of dynamic fracture toughness data of DCI from large scale test series at BAM taking the pearlite content of the microstructure into account.