Original paper(Vol.47 No.5 pp.484)

Effect of surface treatment for fibers on stress relaxation of short fiber reinforced plastics

Hiwa Chiaki; Chikamoto Tadanobu; Nakai Yoshikazu; Tsuji Michihiro

Abstract:The stress strain relation and stress relaxation behavior of short fiber reinforced plastics are affected by coupling agents on fiber surface. In the present study, the shear stress on the interface between fiber and resin in the composites were evaluated from stress relaxation tests and a modified viscoelastic model. In the model, the coefficient of an elastic element is proportional to the ratio of fiber strain to resin strain. The interfacial shear stress in the surface treated fiber composite, which was estimated by the present method, is higher than that in the non treated fiber composite.

Key Words:coupling agent, stress relaxation, viscoelastic model, interfacial shear stress