Experimental Study of Autofrettage

The autofrettage of alloy D16 disks is investigated experimentally. The results of the experimental modeling are compared with the numerical calculations. A mathematical model of plasticity is developed based on the performed cyclic push-pull tests of flat specimens. Additional functions of the previously accumulated plastic strain are incorporated into a nonlinear kinematic hardening model. The damage parameter is included according to the effective stress concept to describe a decrease in the elastic modulus during elastic-plastic deformation. Experimentally obtained distribution of residual circumferential and radial strains has shown a good agreement with the numerical results.