THE INFLUENCE OF STRAIN-RATE ON THE RESIDUAL STRESS FIELDS OF THICK-WALLED CYLINDER

In this paper, the residual stress fields on the autofrettage technique of thickwalled cylinder are analyzed in detail. The experiments concerning the influence of strain-rate on mechanical parameters of gun barrel are carried out under uniaxial tensile and compressive cyclic loading condition. The effects of four different strain rates on the yield stresses, the hardening parameters and the reverse yield stresses have been compared. On the basis of the experimental results, an elasto-visco-plastic model has been proposed to analyze the residual stress fields of autofretted tube under the assumption that the difference between the tensile and the reverse yield stresses is independent of strain-rate.The effects of strain rates on the mechanical autofretted tube are evaluated by using the proposed rate-dependent constitutive model.Some useful suggestions for improving the autofrettage technique are presented