▎ 摘　　要

NOVELTY - A composite material comprises a natural fiber reinforced thermoset polymer. USE - Composite material e.g. composite plate used for layer in ballistic armor in personal vests and military vehicles to protect against rifle shots with caliber 7.62 mm or 5.56 mm for capturing ceramic and projectile fragments resulting from frontal impact (all claimed). ADVANTAGE - The composite material avoids fragmentation of the fragile polyester polymer matrix, thereby allowing the composite plate to maintain its integrity for protection against subsequent firing of rifle and has high impact power. The thickness of the ceramic material is reduced, so that cost and weight of the system can be decreased. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (i) manufacture of the composite, which involves accommodating the fruit fiber of Calotropis giganteafunctionalized with graphene oxide, corresponding to the desired proportion of 30 vol.% within a suitable metal mold, and adding fluid polyester resin and covering the mold; (ii) ceramic material, which has thickness of 7, 8, 9 and 10 mm and is prepared by using alumina doped with niobia in amount of 4 %mass with hexagonal geometry, weighing alumina, niobia and polyethylene glycol powders, in liquid phase, and packing in an alumina ball mill for 12 hours and leaving still for 48 hours in an oven at 80° C for drying; (iii) manufacture of ceramic, which involves macerating and sieving to obtain the powder, pressing under pressure of 30 MPa and taking the obtained green components to the oven to be sintered; and (iv) multilayer armor, which comprises the composite plate, glued with polyurethane adhesive to a ceramic front layer, responsible for eroding the projectile and attenuating its impact.