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In the present study, the ballistic response of chromium/chromium-sulfide cermet, a microstructural ceramic-metal composite, was investigated. The chromium/chromium-sulfide cermet was manufactured using self-propagating high-temperature synthesis, a process wherein the material is created under a self-sustaining combustion reaction between the chromium and sulfur. This type of synthesis allows the creation of near-net shape structures and offers the possibility of tuning material properties and material behavior by changing the reactant composition. High-speed ballistic impact (&1460 m/s) of samples with initial molar ratios of Cr:S ranging from 1.15:1 to 4:1 exhibited a transition in response from purely brittle to quasi-ductile when the molar ratio was at and above 3:1. Microscopy of the impacted samples revealed that this ductility was sustained by significant deformation of metal chromium particles supported in the matrix of chromium-sulfide ceramic. Ballistic depth of penetration experiments at &1715 m/s using thin cermet samples facing a polyethylene cylinder showed a weak dependence of residual penetration on molar ratio.

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The shock response of chromium sulfide, a cermet of potential interest as a matrix material for ballistic applications, has been investigated at two molar ratios. Using a combustion synthesis technique allowed for control of the molar ratio of the material, which was investigated under near-stoichiometric (cermet) and excess chromium (interpenetrating composite) conditions, representing chromium:sulfur molar ratios of 1.15:1 and 4:1, respectively. The compacts were investigated via the plate-impact technique, which allowed the material to be loaded under a one-dimensional state of strain. Embedded manganin stress gauges were employed to monitor the temporal evolution of longitudinal and lateral components of stress in both materials. Comparison of these two components has allowed assessment of the variation of material shear strength both with impact pressure/strain-rate and time for the two molar ratio conditions. The dynamic shear strength of the two material systems are comparable to borosilicate and soda-lime glass. The two materials exhibited identical material strength despite variations in their excess chromium contents.