Bulletproof lightweight metal matrix macrocomposites with controlled structure and manufacture the same

Abstract

The lightweight bulletproof metal matrix macrocomposites (MMMC) contain (a) 10-99 vol. % of permeable skeleton structure of titanium, titanium aluminide, Ti-based alloys, and/or mixtures thereof infiltrated with low-melting metal selected from Al, Mg, or their alloys, and (b) 1-90 vol. % of ceramic and/or metal inserts positioned within said skeleton, whereby a normal projection area of each of said inserts is equal to or larger than the cross-section area of a bullet or a projectile body. The MMMC are manufactured as flat or solid-shaped, double-layer, or multi-layer articles containing the same inserts or different inserts in each layer, whereby insert projections of each layer cover spaces between inserts of the underlying layer. The infiltrated metal contains 1-70 wt. % of Al and Mg in the balance, optionally, alloyed with Ti, Si, Zr, Nb, V, as well as with 0-3 wt. % of TiB , SiC, or Si N sub-micron powders, to promote infiltrating and wetting by Al-containing alloys. The manufacture includes (a) forming the permeable metal powder and inserts into the skeleton-structured preform by positioning inserts in the powder followed by loose sintering in vacuum to provide the average porosity of 20-70%, (b) heating and infiltrating the porous preform with molten infiltrating metal for 10-40 min at 450-750° C., (c) hot isostatic pressing of the infiltrated composite, and (d) re-sintering or diffusion annealing.