Assessment of Ductile Cast Iron Fracture Mechanics Analysis Within Licensing of German Transport Packages

In recent years BAM was involved in several licensing procedures of new package designs for the transport of radioactive material, where the cask body was made of Ductile Cast Iron (DCI). According to IAEA regulations type B(U) packages must withstand the defined accident conditions of transport. For the cask material DCI, it is necessary to determine the brittle fracture behaviour. Due to the complex structure of the cask body and the dynamic loading a fracture mechanical assessment in an analytical way is not always possible. Numerical calculations are necessary to determine the fracture mechanical load in the component. At the first step a numerical analysis has to be done to identify the loading state at the cask body. Secondly an analysis of a detail of the cask body is made considering the boundary conditions of the global model. An artificial flaw is considered in this detailed model to calculate the fracture mechanical loading state. The size of the artificial flaw is characterized by the ultrasonic inspection used for the quality assurance of the package. The applicant developed additional analysis tools for calculation of stress intensity factor and/or J-Integral. The paper describes the authority assessment approach for the DCI fracture mechanics analysis.

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Structure Integrity Evaluation of Supercritical Water Cooled Pressure Tube Subjected to Accident Conditions

Volume 6A: Materials and Fabrication ◽

10.1115/pvp2018-85017 ◽

2018 ◽

Author(s):

Jiacheng Luo ◽

Li Yu ◽

Pengzhou Li ◽

Lei Sun

Keyword(s):

Fracture Mechanics ◽

Supercritical Water ◽

Tube Wall ◽

Probabilistic Method ◽

Supercritical Pressure ◽

Pressure Tube ◽

Mechanics Analysis ◽

Probabilistic Function ◽

The Difference ◽

Accident Conditions

The coolant inside the supercritical water cooled pressure tube operates beyond the critical thermodynamics point of water, and the structure integrity of the pressure tube is of great important to the safety of reactor. Under the accident load, the difference in temperature along the pressure tube wall will cause relatively large thermal stress. Due to the generated high tensile stress, coupled with the internal high pressure load, the defects in the inner surface of the pressure tube may propagate rapidly and even through the wall thickness. This paper investigates the structure integrity of the supercritical water cooled pressure tube based on the deterministic and the probabilistic method of fracture mechanics, and obtains the stress intensity factor and the probabilistic function. It is found that the integrity of the supercritical pressure tube can be maintained from the fracture mechanics analysis under the accident load.

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OS8-26 Hydrogen Absorption Properties and its Effects on the Strain-Rate Dependence of Tensile Fracture in Ferritic Ductile Cast Iron(Fatigue and fracture,OS8 Fatigue and fracture mechanics,STRENGTH OF MATERIALS)

The Abstracts of ATEM International Conference on Advanced Technology in Experimental Mechanics Asian Conference on Experimental Mechanics ◽

10.1299/jsmeatem.2015.14.136 ◽

2015 ◽

Vol 2015.14 (0) ◽

pp. 136

Author(s):

Taishi Ogawa ◽

Takashi Matsuo ◽

Masahiro Endo

Keyword(s):

Cast Iron ◽

Fracture Mechanics ◽

Strain Rate ◽

Hydrogen Absorption ◽

Ductile Cast Iron ◽

Rate Dependence ◽

Tensile Fracture ◽

Absorption Properties ◽

Strength Of Materials ◽

Fatigue And Fracture

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Ductile Fracture Evaluation of Ductile Cast Iron and Forged Steel by Nonliner-fracture-mechanics : Proposal of J-integral Design Curves

The Proceedings of the National Symposium on Power and Energy Systems ◽

10.1299/jsmepes.2000.7.321 ◽

2000 ◽

Vol 2000.7 (0) ◽

pp. 321-326

Author(s):

Akio KOSAKI ◽

Namio URABE

Keyword(s):

Cast Iron ◽

Fracture Mechanics ◽

Ductile Fracture ◽

Ductile Cast Iron ◽

J Integral

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Dynamic Fracture Mechanics Assessments for Cubic Ductile Cast Iron Containers

International Journal of Radioactive Materials Transport ◽

10.1179/rmt.2000.11.1-2.113 ◽

2000 ◽

Vol 11 (1-2) ◽

pp. 113-118 ◽

Cited By ~ 1

Author(s):

U. Zencker ◽

P. Zeisler ◽

B. Droste

Keyword(s):

Cast Iron ◽

Fracture Mechanics ◽

Dynamic Fracture ◽

Ductile Cast Iron ◽

Dynamic Fracture Mechanics

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Ductile Cast Iron for Transportation Cask Bodies

9th ASME International Conference on Radioactive Waste Management and Environmental Remediation: Volumes 1, 2, and 3 ◽

10.1115/icem2003-4528 ◽

2003 ◽

Author(s):

E. P. Warnke ◽

W. Steinwarz ◽

W. Sowa ◽

R. Hu¨ggenberg

Keyword(s):

Cast Iron ◽

Radioactive Waste ◽

Ductile Cast Iron ◽

Nuclear Radiation ◽

Spent Fuel ◽

Accident Conditions ◽

Fuel Elements ◽

And Storage

Casks for transportation and storage are necessary for the handling of spent fuel elements and other radioactive waste. These casks must provide sufficient shielding against nuclear radiation, safe confinement even under severe hypothetical mechanical and thermal accident conditions and assurance of the subcriticality of the content under these conditions. Since more than 20 years ductile cast iron is established as a well qualified and proven material for the fabrication of the cask body of the CASTOR and MOSAIK type casks.

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Ultrasonic Inspection for Microstructural and Mechanical Properties of Ductile Cast Iron

Advanced Engineering Forum ◽

10.4028/www.scientific.net/aef.39.9 ◽

2021 ◽

Vol 39 ◽

pp. 9-19

Author(s):

Özer Özdemir ◽

Selim Gürgen ◽

Melih Cemal Kuşhan

Keyword(s):

Mechanical Properties ◽

Cast Iron ◽

Sound Speed ◽

Ultrasonic Inspection ◽

Flaw Detection ◽

Wide Frequency Range ◽

Ductile Cast Iron ◽

Cast Irons ◽

Ultrasonic Sound ◽

Graphite Morphology

Ultrasonic inspection is a well-known method in non-destructive testing. Based on the changes in the ultrasonic sound speed, tested materials are evaluated in terms of internal defects. In addition to flaw detection, ultrasonic testing is used in the material characterization of ductile cast iron. Graphite shape detection has been widely investigated by ultrasonic inspection in literature. However, most of the measurements has been conducted at single frequencies. In this work, three different nodulizer included casting operations were carried out to produce ductile cast irons having various graphite morphologies. A wide frequency range of 1.25-10 MHz was selected in the ultrasonic inspection. In addition to graphite morphology analyses, the relationship between ultrasonic sound speed and mechanical properties was studied. In the mechanical analyses, hardness and tensile testing properties were investigated for the specimens. From the results, ultrasonic sound speed exhibits a considerable dependency to the graphite morphology. In addition to a good graphite detection capability, ultrasonic inspection exhibits promising results for predicting the mechanical properties such as hardness, elastic modulus, yield strength and tensile strength. It is also found that there is a slight increase in the ultrasonic sound speed by increasing the frequency, although sound speed is independent from this parameter.

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