High security armour plating for e.g. bank vault - is of composite construction with copper sheet and corundum particles embedded in aluminium body

摘要

The high security armour plating for e.g. bank vaults is of a composite aluminium (9), copper sheet (11), and corundum (12) construction. Grains of corundrum (12) are embedded in an aluminium slab (9), and the copper sheet may also be embedded (11) or used as a liner (6). The arrangement combines the mechanical resistance of corundum with the thermo-diffusive properties of aluminium and partic. copper. The embedded copper sheet (11) may be perforated (13) to promote interaction of the inner (16) and outer (17) layers of aluminium and, thus, reduce the likelihood of lamination. The perforations (13) may be formed by punching with the cut-outs (14) remaining attached, and cantilevering out obliquely to form a shear key with the aluminium.