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of velocity from 1450 m/s to 2100m/s. Zr-based metallic glass composites with 80% Volume fraction and 0.3mm diameter of tungsten fiber were used to perforate 30CrMnMo steel plates. According to the result, we find: firstly, the penetration efficiency is influenced by properties and structure of the material, which is helpful to design the rod penetrator of composite material. Secondly, for the different structures of the penetrator, curves of penetration depth with velocity are different. The curves of two segments and three segments are convex, and at 1750m/s~1800m/s and 1850m/s they arrive at the maximums which are both 1.7L, respectively. And for the monolithic penetrator, the curve is asymptote, but after 1850m/s, the penetration depth arrive to the hydrodynamic limit which is L*(r_p/r_t)_1/2, and it is about 1.5L. Finally, according to the dynamic damage characteristic of the unidirectional fiber reinforced composite materials, the characteristic of dynamic crack propagation and penetration velocity of impact, optimal segmentation is defined, and analysis the problem from (2), provide the reference for structure design of segment penetrator.