Cost Comparison of Existing Coatings for a Hypervelocity Test Rail

This study compared the relative costs, to the Department of Defense, of two different coatings used to protect a high speed test rail. Each coating was compared to the case of an uncoated rail with test conditions that caused catastrophic failure just after the test sled reached its maximum velocity. The total cost was finalize3d on a per test basis in order to sum cost of various expenditures that may only happen once every few tests. To compare the protective properties of each coating, various coated and uncoated samples were tested via a cylinder specimen Taylor Impact Test. Each coating's protective properties, or coating effectiveness, were found by its radial deformation change at the impacted end of each cylinder relative to the uncoated cylinder. This deformation change, relative to the uncoated cylinder's deformation, is the coating's effectiveness. Taylor Test results were then analyzed using the CTH hydrocode. CTH is able to model Taylor Impact Tests. CTH was used to understand the internal workings and results of the Taylor Tests in more depth. Verification between CTH and experimental Taylor Tests was done using final values for length, diameter and undeformed length of the cylinder.