Gouge development during hypervelocity sliding impact

The sliding interface of a hypersonic flyer/target system is subject to immense forces due to dynamic loads and the highly oblique impact of the flyer with the target. Under these severe loading conditions, the material in both the flyer and target will experience large non-linear deformation known as gouging. Using the hydrocode CTH, a numerical model of the gouging process has been created and studied to examine the underlying physics of the phenomenon. Results of simulated gouges are presented along with a discussion of the mechanics involved. Under the combination of a normal load sufficient to cause penetration of the flyer into the target, and hypervelocity tangential motion, stresses may exceed the plastic flow stress of the materials. In this case, material jets may develop at the material interface and impinge into the adjacent material. This jet formation, and the material deformation it causes, are the underlying causes of gouging.