Tensile deformation of nylon 66 fibers at −196°C



Nylon fibers tested in tension at −196°C show ductile strains up to 75%. The ductility is a complicated function of draw ratio, because decreasing work hardening with decreasing draw ratio leads to a point of instability where necking begins. The necks presumably initiate fracture, have the appearnce of cracks, and have been previously seen on fibers drawn in various organic liquids. Recovery experiments showed that molecular motions involved in low temperature deformation differ from those involved in ambient temperature deformation.