Abstract: An obvious mass abrasion of kinetic energy projectile is generated in the process of high-speed penetration into concrete target. The mass abrasion seriously affects the penetration performance of projectile. A series of high-speed penetration experiments were carried out to further study the internal mechanism of projectile abrasion during penetration. The specimens for microscopic observation were prepared from the nose of residual projectile by linear cutting technique. The microstructures at multiple observation points on the surface of residual projectile were systematically observed by metallographic microscope and scanning electron microscope. The results show that there is an obvious heat affected zone on the surface of residual projectile，and there are many long grooves parallel to each other on its surface. In addition，a few microcracks are observed at the tip of projectile nose，which contribute to the mass loss of the tip of projectile nose，but have little influence. Through the microscopic observation，it is found that the mass abrasion of projectile is not caused by a single mechanism，but is a complex process of different mechanisms interacting with each other.

Key words: kineticenergyprojectile, high-speedpenetration, massabrasion, reinforcedconcrete, microscopicanalysis