Institute for Materials, Science and Engineering

Bücher

Angebote / Angebote:

Excerpt from Institute for Materials, Science and Engineering: Polymers, Technical Activities, 1989The Polymers Division is responsible for providing standards, measurement methods, and fundamental concepts of polymer science to assist U. S. Industries that produce or use synthetic polymers in essential parts of their business. This broad mission does not change markedly with time but the specific technical programs within this broad mission must be continually assessed to meet the industry's changing priorities.This year we expanded our program in polymer matrix composites. While these materials have been used for some time as high performance laminates for the defense and aerospace industries, their use in a wider variety of civilian markets has been inhibited by several technical factors. An important barrier is that the low volume lay-up processes used to make very high performance aerospace parts cannot be easily adapted to higher production volumes and lower part costs. There is a need to provide a science base for composite processing methods that-have broader potential applications to civilian transportation, machinery, electronics, and construction markets.Following the recommendations of industry representatives, our program emphasises study the behavior of polymers in transfer molding or reaction injection molding processes. Preliminary work on modeling such processes is described in this report. Flow visualization experiments will be carried out during the coming year to provide data to verify and refine such models.A second barrier to the more widespread use of polymer composites is our limited ability to measure and understand the way these materials perform or fail in service. The highly anisotropic properties that allow composites to be tailored for a specific application make their failure behavior very complex. Composite properties are also highly dependent on their processing conditions. This means that a meaningful composites program must integrate the mechanics of composites with an understanding of the materials science of the polymer matrix, the fibers, and the in¿uence of process conditions. This is the goal of the next phase of the program.About the PublisherForgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.comThis book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully, any imperfections that remain are intentionally left to preserve the state of such historical works.