Widmanstatten structure (widmanstatten structure)
welding heat affected zone in the overheated zone, the austenite grain looks very thick World steel pipe network editing , coarse austenite in the fast cooling will form a special overheating of the organization, its organizational characteristics of the formation of parallel ferrite (cementite) in a coarse austenite grain needle-chip, the remaining austenite between the ferrite needle piece last into pearl body, this overheating of the organization known as the Widmanstatten structure of ferrite (cementite) World steel pipe network editing . The
widmanstatten not only coarse grains, but also because of the fragile side of a large number of needle-chip ferrite formation, the sharp decline in the toughness of the metal, which is less hardened steel welded joints become brittle and the one of the main reasons.