Characterization of ballistically deformed tungsten [100]-, [111]-, and [110]-oriented single crystal penetrators by optical metallography, x-ray diffraction and transmission electron microscopy

Single-crystal penetrators of tungsten having orientations of [100], [111], and [110] were ballistically deformed into targets of standard armor material and characterized by optical metallography, x-ray diffraction, and transmission electron microscopy (TEM) methods, which showed significant differences in their deformation mechanisms and microstructures corresponding to their deformation performance as measured by the penetration of the target. The [100] single-crystal penetrator, which produced the most energy efficient deformation, provided a new, alternative mechanism for ballistic deformation by forming small single-crystal blocks, defined by {100} oriented cracks, which rotated during extrusion from the interior to the side of the penetrator while maintaining their single crystal integrity. The [111] single-crystal penetrator transferred mass along allowed, high-angle deformation planes to the penetrator’s side where a buildup of mass mushroomed the tip until the built-up mass let go along the sides of the penetrator, creating a wavy cavity. The [110] penetrator, which produced the least energy-efficient deformation, has only two allowed deformation planes, cracked and rotated to invoke other deformation planes.