Abstract: A composite plate formed of aluminium alloys, having high characteristics of resistance to dynamic penetration by hard bodies, comprising three "components" which reciprocally contact one another in a superimposed position and are welded on their respective contact surfaces, the "central" component possessing very high mechanical strength and hardness properties, while the other two components (respectively "front" and "inner" components) possess high toughness and good weldability properties.Said three "central", "front" and "inner" components have a tensile strength respectively comprised in the following ranges: from 540 to 735 N/mm.sup.2, from 345 to 540 N/mm.sup.2 and from 290 to 520 N/mm.sup.2, and a thickness respectively comprised between the following percent values in respect of the total thickness of the composite plate: 35-62%, 19-32.5% and 19-32.5%.