抄録
Polymeric material is used in such fields as electricity and electronic parts. In this report, deformation behaviors of water absorbed nylon66 after pre-strain are investigated under biaxial stresses to establish the constitutive model. A series of equi-strain loci after tensile and torsional pre-strains can be expressed numerically in Mises type stress plane by considering hydrostatic pressure effect in flow stress. By using the obtained equations of the equi-strain loci and the normality rule with respect to plastic strain incremental vector, stress paths are calculated at loading along various strain paths with a corner of various angle. It is confirmed that rather good agreement can be obtained between experimental and predicted results on stress-strain curves of water absorbed Nylon66 in reloading after pre-strains.
