Abstract: Based on the launching characteristics of an electromagnetic railgun, the formation mechanism of railgun gouging was analyzed, and the formation process of railgun gouging was numerically simulated by using the finite element code ABAQUS. The results show that the transient particles caused by heterogeneous temperature distribution can indeed cause gouging to occur. The simulated gouging shape is in agreement with the experimental one. The degree of gouging damage mainly depends on the armature velocity and the effective damage contact area between the armature and the rail, while the interface load has little effect on it. The materials at high temperature are easily vulnerable and can shorten the working life. By using hard rail materials, gouging can be prevented, but it will decrease the electrical conductivity and launching efficiency. Consequently, the keys to antigouging are determining the balance between the hardness and the conductivity of materials according to actual requirements and overcoming the limitations of the metal processing technologies through the structural innovations.