innovations in safety analysis of dissimilar metal...
TRANSCRIPT
Project LOST:Innovations insafety analysisof dissimilarmetal weldsSebastian Lindqvist
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Cracks have been detected in dissimilar metal welds– safety class 1
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Weld metal, Lincoln TIG 316L &LNS 316L, P240
Ferritic steel,15H2MFA
Buttering layer 1, EA-395/9
Buttering layer 2, EA-400/10T
Buttering layer 3, EA-400/10T
Austenitic stainless steel,X6CrNiTi18-10
Low alloy steel
18MND5
(ferritic steel)
Stainless steel
316LNi-base
Alloy 52
(weld metal)
Current methods to determine the lower boundary fracturetoughness properties are developed for homogeneous materials –Safety concerns when applied to dissimilar metal welds?
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Fracture toughness = J
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Fracture toughness = J or K
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Area of theremaining ligament
Fracture toughness = J
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Remainingligament
Energy stored inthe specimen
Fracture toughness = J
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Remainingligament
Energy stored inthe specimen
Parameter relating themeasured workto the fracture toughness
The η-factors developed for homogeneous materials can be usedfor cracks on the interface between a hard and a soft material
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Crack path –brittle andductile regime
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Lower boundary fracture toughness values areobtained at the fusion boundary, the weak zone
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The model can be used for predicting the fracturetoughness of/adjacent to the weakest zone
Transferability
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Towards better operation of NPPs by utilizingthe full potential of fracture mechanics
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Longeroperation
New material solutions
Reduced material consumption
