Development of low activation ferritic alloys for fusion
- Univ. of Santa Barbara, CA (United States)
- Pacific Northwest Lab., Richland, WA (United States)
- Oak Ridge National Lab., TN (United States)
This paper proposes a strategy for developing ferritic alloys based on better understanding of irradiation induced microstructural changes and the consequences of these changes to deformation and fracture. Current methods of estimating embrittlement based on Charpy impact testing are severely limited. Different measures of the DBTT may vary 100 to 200{degrees}C depending on the details of the test method. Further, thin surface-cracked structures have a far higher toughness that large deeply cracked pressure vessels. A far more quantitative, concurrent design based approach to assessing stress and strain limits in flawed structures is proposed; this method incorporates the effects of temperature, strain rate, crack-structure size scales and loading geometries and compliances by measuring the local resistance to fracture in the vicinity of a notch or crack as modified by irradiation-induced microstructural changes. The conditions leading to fracture are related to remote stresses and strains using the finite element method (FEM), incorporating constitutive laws that are also modified by irradiation. Small specimen techniques are used to measure local fracture resistance and the constitutive properties. The local approach also provides a framework for modeling irradiation effects and designing radiation resistant alloys. The leading ferritic candidate alloys are fully martensitic quenched and tempered steels containing about 7-9% Cr, 1-2% W (reducing the activation by replacing Mo) and varying amounts of microalloying elements such as V and Ta.
- OSTI ID:
- 196945
- Report Number(s):
- CONF-940664-; TRN: 95:005767-0114
- Resource Relation:
- Conference: ISFNT-3: international symposium on fusion nuclear technology, Los Angeles, CA (United States), 27 Jun - 1 Jul 1994; Other Information: PBD: 1994; Related Information: Is Part Of Third international symposium on fusion nuclear technology; PB: 362 p.
- Country of Publication:
- United States
- Language:
- English
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