Rate Dependence and Short Term Creep Behavior of PMR-15 Neat Resin at 23 and 288-C

<p>This research focuses on experimental investigation of rate-dependent behavior and short-term creep of PMR-15 neat resin at 23 and 288 C. Effect of loading rate on monotonic stress-strain behavior was explored in monotonic tests at constant stress rates of 0.75 0.075 and 0.0075 MPa/s at 23 and 288 C. In addition effect of prior stress rate on creep behavior was explored in creep tests preceded by uninterrupted loading to a target stress. At each temperature three creep tests were conducted for a given stress level where loading rate was changed from test to test. Creep stress levels were 30 and 25 MPa at 23 and 288 C respectively. Also the effect of stress and strain at the beginning of the creep period was studied in stepwise creep tests where specimens were subjected to a constant stress rate loading with 1800 s creep periods at 5 MPa stress intervals. Specimens were loaded to a maximum stress then unloaded to zero stress with creep periods during loading and unloading. Finally the effect of loading rate was studied in recovery tests where specimens were monotonically loaded to 30 MPa and unloaded to zero MPa then recovered for 12 hours.</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>