Determination of the Constitutive Equations for 1080 Steel and VascoMax 300

<p>The objective of this research is to establish a better representation of the components utilized in a gouging event being considered in research leading to a better understanding of the Holloman High Speed Test Track. Gouging occurs when two metals are traveling at a slight incline to each other at velocities nearing 1.5 kilometers per second and results in a structural failure of both the metals. The gouging process occurs at very high strain rates which results in non-linear stress-strain relations. The coefficients that lead to the Johnson-Cook equations have been determined by the Split Hopkinson Bar test for 1080 steel and VascoMax 300. The Split Hopkinson Bar test was conducted using various strain rates and temperatures to produce meaningful stress-strain relations for both of the steels. These relations allowed a fit of the data to yield specific material coefficients defined in the Johnson-Cook constitutive model. Both the 1080 steel and Vascomax 300 models showed excellent approximation of the plastic region. Verification of the constitutive models was conducted through the use of Taylor tests. A Taylor test model utilizing the constitutive equations was developed in CTH and produced deformation profiles that closely resembled specimens taken from experimental Taylor tests. The end result of this work will be utilized in further studies toward overall high energy impact evaluation.</p><p>This work has been selected by scholars as being culturally important and is part of the knowledge base of civilization as we know it. This work was reproduced from the original artifact and remains as true to the original work as possible. Therefore you will see the original copyright references library stamps (as most of these works have been housed in our most important libraries around the world) and other notations in the work.</p><p>This work is in the public domain in the United States of America and possibly other nations. Within the United States you may freely copy and distribute this work as no entity (individual or corporate) has a copyright on the body of the work.</p><p>As a reproduction of a historical artifact this work may contain missing or blurred pages poor pictures errant marks etc. Scholars believe and we concur that this work is important enough to be preserved reproduced and made generally available to the public. We appreciate your support of the preservation process and thank you for being an important part of keeping this knowledge alive and relevant.</p><br>