This Article Full Text (PDF) References Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Genidy, M. S. Articles by Russell, J. D. Search for Related Content Social Bookmarking                         What's this?

A New Method to Reduce Cure-Induced Stresses in Thermoset Polymer Composites, Part II: Closed Loop Feedback Control System

Dept. of Mech., Aero. & Eng. Sci., 414 Dougherty Eng. Bldg., The University of Tennessee, Knoxville, TN 37996-2210

Madhu S. Madhukar

Dept. of Mech., Aero. & Eng. Sci., 414 Dougherty Eng. Bldg., The University of Tennessee, Knoxville, TN 37996-2210

John D. Russell

Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson AFB, OH 45433-7750

A closed loop feedback control system has been developed to obtain cure cycles which reduce the cure-induced stresses in single fiber/matrix model composites. In this feedback system, thermal expansion and stress relaxation are used to counteract the stresses resulting from the chemical shrinkage. The feedback system is applied to two different fibers (carbon and glass) in four different resins [3501-6, 934, and 977-3 epoxies and 5250-4 bismaleimide (BMI)]. The completeness of the cure is verified by comparing glass transition temperature (T_g) for polymers cured using the standard cure cycles (cycles recommended by the prepreg manufactures) and the feedback cure cycles. The durations of the feedback cure cycles are within that of the standard cycles. Test results indicate that feedback cure cycles reduce the curvature of unsymmetrical laminates as a measure of residual stresses.

Key Words: cure cycle • optimization • feedback control • residual stresses • stress relaxation • thermosets • volume changes

Journal of Composite Materials, Vol. 34, No. 22, 1905-1925 (2000)
DOI: 10.1106/3M0Y-44XM-6WP8-WT7J


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				C. Dong Modeling the Dimensional Variations of Composites Using Effective Coefficients of Thermal Expansion Journal of Composite Materials, October 1, 2009; 43(22): 2639 - 2652. [Abstract] [PDF]