Metal gouging at low relative sliding velocities

Abstract Surface gouging by metals in high-velocity sliding contact has been observed for more than thirty years in engineering applications involving rocket sleds, two-stage gas guns and electromagnetic railguns. The onset of gouging is usually observed to occur at sliding velocities in excess of 1000 m s −1 . Previous investigations of the phenomenon have indicated that the gouging onset velocity is proportional to the yield strength and hardness of the materials involved. In this research, data from reported instances of gouging are used to develop a graphical, linear correlation between gouging onset velocity and yield strength of the sliding material. This correlation is extrapolated into a velocity regime below that in which gouging is usually observed and then serves as the basis for an experiment intended to produce gouges. In the experiment, incipient gouges are produced on lead sheets at sliding velocities as low as 245 m s −1 , well below those at which gouging had previously been reported and in a material never-before reported to have gouged, confirming the validity of the extrapolation.