Adiabatic Shear Instability: Observations and Experimental Techniques

Abstract

Although an extensive literature exists on experimental studies of adiabatic shear banding in metals¹ and shear bands have been studied in polymers at low rates of deformation² very little has been published on adiabatic shear bands (ASBs) in polymers at high rates of deformation (see Adiabatic Shear Instability: Theory). Most studies on polymer failure during impact have largely been concerned with fracture³, ballistic impact⁴, and sensitisation of energetic materials⁵. As ASBs are often precursors to fracture, it is not always clear from post-mortem examination of a specimen whether shear-bands were present before fracture took place, particularly if the fracture was partially or entirely mode III. The rubbing together of the free surfaces can destroy crucial evidence of the nucleation and growth of the bands.