Compression Mechanics of Cylindrical Samples with Radial Deformation Limitation

The presented work aims to construct a plasticity diagram for graphite-containing cast iron SCH20, which is necessary to predict this material’s ultimate deformation values for deformation conditions with significant negative values of the stress state’s coefficient. It has been established that low-plasticity cast iron can be plastically deformed only at negative values of the stress state’s stiffness coefficient. For the first time, the cast iron SCH20 deformation data with significant negative values of the stress state’s stiffness coefficient has been calculated. A technique has been developed to construct a plasticity diagram for low-plastic materials with negative values of the stress state’s stiffness coefficient. A compression model of a cast-iron tubular sample is obtained, which ensures the creation of large plastic deformations and the calculation of stress-deformed state parameters. Calculations performed using the developed model made it possible to establish the studied material’s ultimate deformation, accumulated before fracture, at significant negative values of the stress state’s stiffness coefficient. Modeling performed according to the proposed methodology using the DEFORM software package showed good overlapping between the calculated data and model experiments results.