TEM Observation of Shear Bands in Ti-6Al-4V and AISI 6140 Steel

The fragments contained adiabatic shear band (ASB) in Ti-6Al-4V and AISI 6140 steel were studied by scanning electron microscope (SEM) and transmission electron microscope (TEM). The results show the structure of shear bands in Ti-6Al-4V and AISI 6140 steel being microgranular with average diameter less than 0.3 m. The granula exhibit some preferred orientation, its electron diffraction patterns appear some discontinous rings. The dislocation density is very low in the ASB; adjacent matrix granulas are highly dislocated. No evidence of a phase transformation within the ASB is observed.