EBSD Analysis of an Austenitic Cr-Ni Steel Laser Weld

The results of EBSD analysis of weld zones in CO2 laser-welded corrosion-resistant titanium-containing 12Kh18N10T steel sheets are presented. The structure of narrow (1.03-1.15 mm) welds has been found to be typical of cast metal. There are equiaxed grains with an average size of 40 mu m in the central part of the weld and elongated grains with a maximum length of 200 mu m on the sides of the weld, in the direction of active heat removal, inside which a subgrain structure is observed in EBSD images. The heat affected zone (HAZ) width is from 0.4 to 0.7 mm. The structure in the HAZ is of a recrystallized type. The misorientation inside grains is less than 2 degrees. The grain size is from 10 to 25 mu m. The weld contains a small number of deformed crystallites, which plays a positive role for the structural strength of the joint, since it ensures a low level of residual stresses and their gradients. Ultimate tensile strength of the weld is 650 MPa, which corresponds to the strength of the base metal. The results, indicating the significant role of the texture of the metal in different regions of the weld in ensuring its strength on the level of the base metal, are presented.