Shock-induced amorphization in ultra-fine grained pure copper

It is not easy to find amorphization in monocrystalline materials. This study demonstrates that amorphization can be introduced in ultra-fine grained copper by a novel technique- dynamic severe plastic deformation. High-resolution electron microscope observations reveal the crystalline-to-amorphization transition under an ultrahigh strain rate (~ 10 6 s −1 ) and large shear strain (200%). These experiments show that the localized amorphization might be introduced by profuse dislocations and stacking faults nucleation and their strong interactions under extreme loading condition by molecular dynamics simulations. Our works also point to the onset of localized amorphization as a potential ultra-high strain rate deformation mode. Graphical abstract