Creep and Stress Relaxation Behavior of Homogeneous and Reinforced Compliant Mechanisms and Segments

Abstract

Two critical disadvantages of compliant mechanisms constructed of engineering plastics are poor creep and stress relaxation resistance. Metallic reinforcement is investigated as a method to improve the creep and stress relaxation behaviors of compliant mechanisms and compliant segments. The stress relaxation and creep behaviors of homogeneous compliant segments are compared to those of metallic reinforced compliant segments. Special specimens and fixtures were designed for conducting physical tests. Test results show that metallic reinforced compliant segments significantly outperform homogeneous compliant segments with respect to both creep and stress relaxation. This vein of research is undertaken using metallic reinforcement (inserts) toward the development of a new class of compliant mechanisms with significantly greater performance, particularly insofar as the problems of fatigue and creep are concerned.