Dynamic Strength Estimates for a High Strength, Experimental Steel

For several years, the Air Force has been engaged in the development of high velocity air to surface missiles. The objective is to replace larger, high mass weapons with smaller, more versatile projectiles that can achieve the same goals. The reduction of mass requires that the impact velocity be increased to meet the performance requirements. This has presented researchers with several challenges. First, the steel must be such that it survives the initial shock at impact. Second, because the tunnel is long, the material must resist friction and wear, which could erode the projectile nose, thereby degrading performance. The purpose of this paper is to present the results of dynamic testing of an experimental, high-strength steel. Using a one-dimensional model for the Taylor cylinder test, the constitutive behavior of the steel as a function of strain and strain-rate can be assessed through a strain-rate of roughly 10⁵/second. This behavior is consistent with that required for successful modeling of the response of a penetrator casing in the ultra-ordinance velocity range.