Comparison of different methods to estimate the fracture toughness of metal of welded structure operated in Arctic conditions

Authors: A.V. llyin, V.Yu. Filin, D.M. Artemiev 

Abstract

Fracture toughness of the metal of welded joints is determined as per the Register rules with specimens of particular types (rectangular SENB, C(T)) in full thickness providing for a high constraint in a crack tip. For test temperatures below — 40 °C a high data scatter is observed, fracture toughness values often do not meet the requirements. The problem of excessive conservatism of test conditions in comparison to loading of a crack-like flaw containing structure is actively discussed abroad owing to the forthcoming revision of ISO standards for Arctic materials. The test results are compared and brittle fracture conditions for different specimen types are analyzed, including specimens with simulated welding heat. 
Key words: fracture toughness tests, Arc-steels, welded joints, SENT.

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About authors

Ilyin Aleksey - DSc, FSUE "Central Research Institute of Structural Materials "Prometey, St. Petersburg " 
mail@crism.ru


Filin Vladimir - PhD, FSUE "Central Research Institute of Structural Materials "Prometey", St. Petersburg 


Artemiev  D.M. - FSUE "Central Research Institute of Structural Materials "Prometey", St. Petersburg 



Issue: 40/41 (2015)






For citation: A.V. llyin, V.Yu. Filin, D.M. Artemiev. Comparison of different methods to estimate the fracture toughness of metal of welded structure operated in Arctic conditions. Research Bulletin by Russiann Maritime Register of Shipping. 2015, No. 40/41, pp. 62-71.

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UDC:  669.14:620.17:539.4
Pages:  62 - 71