In this work, T2 red copper and high nitrogen austenitic stainless steel (HNASS) were explosively welded for the first time. The welding window was theoretically developed, and the experiment was designed by considering the effect of explosive loading on welding quality. To evaluate the welding quality, the microstructure and mechanical properties of the composite material were systematically investigated. The results showed that the welding quality was in good agreement with the results predicted by the welding window. The micromorphology of the welding interface changed with a varied welding parameter, and no intermetallic compounds were found at the welding interface by EDS analysis. The microhardness of the two raw materials both increased near the welding interface, and the enhancement increased with the explosive loading. The failure pattern of the welding interface in the tension-shear experiments was dominated by the strength failure of the red copper.

To determine the ballistic limit velocity of titanium–titanium tri-aluminide (Ti/Al3Ti)-laminated composites under the action of tungsten alloy spherical fragments, a type of 12.7 mm ballistic gun loading system was used to test the tungsten alloy spherical fragments vertically impacting the Ti/Al3Ti-laminated composite targets with different thickness. The relationship between the ballistic limit velocity and the target area density of the Ti/Al3Ti-laminated composite was obtained. As the area density increased, the ballistic limit velocity and the ballistic energy absorbed by the target plate also enhanced. Based on the dimensional analysis and similarity theory, a simulation law of tungsten alloy spherical fragments penetrating Ti/Al3Ti-laminated composite targets with different thickness was studied and an empirical formula for the ballistic limit velocity was obtained. The research results had an important application value for the optimal design of the light armor protection structure.