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A large scatter in impact energies was found in four Charpy V-notch impact samples taken from BC850 hot-rolled steel and tested under same conditions i.e.experiment temperature ( - 20℃ ) and impact force.The origin of the observed scatter has been investigated using combined EDS and EBSD analysis in an SEM.EDS maps showed evidence of manganese segregation,while EBSD data showed the major phase in this steel was ferrite with a small fraction of martensite.The micro-texture of the ferrite phase in all the samples investigated was also similar.There was,however,a marked difference in the distribution and size of the martensite islands,which was inferred to result in the differences of impact properties :larger martensite islands resulted in lower impact properties while structures with finer islands had higher impact strengths.It is recommended that the hot-rolling process should optimized to produce a uniform homogeneous microstructure in order avoid scatter in impact properties.