▎ 摘　　要

NOVELTY - A composite material comprises a thermosetting polymer reinforced with natural fibers. USE - Composite material e.g. composite plate for preparing ceramic material and multilayer armor used in personal vest and military vehicle (all claimed). ADVANTAGE - The composite material captures ceramic and projectile fragment from frontal impact, and protects against firing of rifle with ammunition of high impact power. The lightweight ceramic material is economically manufactured, and has reduced thickness. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: production of the composite material, which involves accommodating ramie fibers functionalized with 30 vol.% graphene oxide, inside a suitable metallic mold, and adding epoxy resin functionalized with graphene oxide still fluid and covering the mold; a composite plate, which comprises ramie fibers reinforcing an epoxy matrix and functionalized with graphene oxide using as a layer in multilayer armor to protect against rifle shots with ammunition calibers of 7.62-5.56 mm; a ceramic material, which has a thicknesses of 7-10 mm. The ceramic material is prepared by using alumina doped with 4 %mass niobium pentoxide with hexagonal geometry, weighing and packing the powders of alumina, niobium pentoxide and polyethylene glycol, in liquid phase, in an alumina ball mill for 12 hours, and leaving for 48 hours in an oven at 80° C for drying; manufacture of the ceramic material, which involves macerating and sieving to obtain the powder, pressing under a pressure of 30 MPa, and taking the green component to the oven to be sintered; and a multilayer armor, which comprises the composite plate glued with polyurethane adhesive to a ceramic front layer.