Microstructural Characterisation of a High Strength Steel Subjected to Localised Blast Loading

The blast response of a High Strength Steel (HSS), classified as a High Hardness Armour (HHA), subjected to a 60 g charge mass at a Stand-Off Distance (SOD) of 25 mm has been investigated. Electron Backscatter Diffraction (EBSD) and microhardness measurements were used to determine the microstructural evolution in the through thickness and the associated mechanical properties changes. Results show that the blast wave travelling through the material increased the deformation and reduced the grain size. These observations correlated with the hardness increasing along the direction of travel of the blast wave.