THE INFLUENCE OF EXPERIMENTAL-DESIGN ON DEPTH-OF-PENETRATION (DOP) TEST-RESULTS AND DERIVED BALLISTIC EFFICIENCIES

Experimental data for ceramic armor materials from two test methods, s mall-scale reverse ballistic tests and depth-of-penetration (DOP) test s, are reviewed and compared. Results from reverse ballistic tests can be used to estimate the length of rod erosion in the ceramic tiles of DOP tests. The outcome of a given DOP test can then be predicted by u sing recently published data bases on RHA penetration to determine the residual penetration into the steel back-up of the DOP test. Results of this methodology, compared to experimental DOP-test results, agree reasonably well for aluminum nitride and silicon carbide, even though scale sizes, impact velocities and experimental procedures varied cons iderably between investigators. The methodology was then applied to si ngle-valued performance criteria for ceramic armor materials, for exam ple, mass efficiency. This analysis demonstrates that in certain cases , test parameters, like the ratio of penetrator length to ceramic tile thickness, affect test results considerably more than differences bet ween ceramic types. Thus, DOP tests must be properly designed and inte rpreted in order to assess correctly the ballistic performance of cera mics. (C) 1997 Elsevier Science Ltd.