Ballistic Response of Chromium/Chromium-Sulfide Cermets

Abstract

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.