Effect of microstructure on fracture toughness of coarse grain heat aff ected zone in as welded X70M steel

Cagırıcı, Mehmet
Tosun, Uygar
Gür, Cemil Hakan
Fracture toughness behavior of coarse-grain heat affected zone (CGHAZ) of the welds in API5LX70M pipes has been investigated by Charpy impact and crack tip opening displacement (CTOD) tests at -10°C. The present work also includes comprehensive pre- and post-test metallography and analyses. A correlation between local brittle and soft spots in intercritically reheated coarse-grain heat affected zone (ICCGHAZ) and toughness of the as-welded material has been observed. The degree of dilution and the microstructure of ICCGHAZ varied dramatically with heat input while there is no considerable change in the prior austenite grain size. It has been concluded that orientation and distribution of the secondary phases are the governing factors on toughness behavior of the as-welded steel.


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Citation Formats
M. Cagırıcı, U. Tosun, and C. H. Gür, “Effect of microstructure on fracture toughness of coarse grain heat aff ected zone in as welded X70M steel,” presented at the 18th International Metallurgy and Materials Congress , 29 Sept. - 01 Oct. 2016, Istanbul, Turkey, 2016, Accessed: 00, 2021. [Online]. Available: http://www1.metalurji.org.tr/immc2016/IMMC2016_Bildiriler.pdf.