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Generally,microstructures of coiled hot-rolled strips of micro-alloyed high-strength steel grades are quite complex and not easily quantifiable by conventional methods such as light optical microscopy.During the last decades,scanning electron microscopy ( SEM) and electron backscatter diffraction ( EBSD) have become useful tools for the characterization of complex microstructures.The EBSD data provides an immense variety of post- processing possibilities,e.g.related to grains,grain boundaries,misorientation or texture.The analysis enables a more detailed characterization of the constitution of ferrite such as its sub-grain structure,dislocation structure,meso-texture described by the distribution of misorientation angles between neighbouring grains.Furthermore,effective grain size which may better match micro-mechanism controlling the cleavage initiation and propagation process in the brittle temperature regime is more relevant for describing toughness properties.The impact of microstructural features on technological properties like yield strength,yield ratio and toughness identified in the Charpy impact test are discussed.