An Experimental Study on the Effect of Curvature-Rate at Preloading Stage on Subsequent Creep or Relaxation of Thin-Walled Tubes under Pure Bending

Abstract

Pure bending with a constant curvature-rate followed by creep(hold constant moment for a period of time)or relaxation(hold constant curvature for a period of time)tests were conducted to investigate the effect of prior curvature-rate at preloading stage on the subsequent creep of relaxation behavior. Thin-walled tubes of 304 stainless steel were used in this investigation. The curvature-ovalization measurement apparatus, designed by Pan et al.⁽¹⁾ was used for conducting the present experiments. It has been found that the curvature-rate at the preloading stage has a strong influence on the subsequent creep or relaxation deformation under pure bending.