Characterization of the microstructure, crystallographic texture and segregation of an as-cast duplex stainless steel slab

The microstructure of a duplex stainless steel slab 1.4362 produced by continuous casting has been investigated by optical microscopy, scanning electron microscopy, EBSD and EDS. The slab showed different macrostructures through the thickness. The macrostructure can be divided into 3 types: fine equiaxed, columnar and coarse equiaxed grains. In all three regions, the volume fraction of each phase austenite and delta-ferrite is close to 50% and the hardness is very similar for both. The austenite has Kurdjumov-Sachs or Nishiyama-Wassermann relationship with the delta-ferrite. The slab does not show a strong segregation profile through the thickness. The delta-ferrite is enriched in Cr and Mo, while austenite is enriched in Ni and Mn.