A bstractThis paper has an purpose to study the effect of C on the toughness of YS 460 MPa FCAW weld metal. These effects were evaluated by charpy impact and CTOD test about 4 FCAW weld metal containing various C and Si content in relation to microstructure. Increase of C content was helpful to increase AF volume fraction and reduce PF(G) and FS volume fraction by increasing super cooling rate for ferrite transformation. Also, Increase of C content up to 0.045wt% made the strength and impact toughness higher by increasing AF volume fraction. The weld metal containing higher C content indicated higher CTOD value. It is because the volume fraction of PF(G) and FS, can play a role as crack initiation site, was reduced. Effect of C on the strength and elongation of weld metal was higher with an increase of Si contents.
This study investigated the effect of Si on the characteristics of FCA multi-layer weld metal with 460 MPa yield strength grade steels for ships and marine structures. The effect on microstructure was evaluated by tensile, charpy impact and CTOD testing of 4 FCAW welds containing various C and Si contents. C content affected weld metal properties depending on Si content, microstructure, strength and impact value. With lower C content, strength and impact value increased when Si content was reduced, because of higher AF volume fraction. With higher C content, those properties were little affected by Si content. These phenomena indicate that C affects phase transformation more than Si. The CTOD value was higher with lower Si and higher C content. This was interpreted to mean that a lower volume fraction of not only PF, FS but also the M-A phase, can affect crack initiation sites, due to higher C and lower Si contents.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.