Damage of materials under proportional loading

The work is devoted to the study of material damage during elasto-plastic proportional loading, in particular, the influence of two loading mechanisms, detachment and shear, is taken into account. These mechanisms include viscous, brittle, and visco-brittle modes of failure. The accumulation of scattered damage is considered as a multi-scale and multi-stage phenomenon that occurs during proportional loading at the micro- and meso-levels of the destruction of the metal structural material. As part of the study, a quantitative assessment of the degradation of the physical and mechanical properties of materials was performed, in particular, changes in the modulus of elasticity E and G, and the definition of equivalent damage arising from an elastoplastic proportional load is proposed. Experimental data on the kinetics of damage accumulation on 12X18N10T steel samples, which were subjected to axial load (tension), shear (torsion) and proportional load with the stiffness parameter of the stress state K = 0.5 before failure, are considered. The work compares experimental results with theoretical data, damage accumulation. The obtained conclusions contribute to a deeper understanding of the mechanisms of destruction of materials under the action of a proportional load, and can also find practical application in the design and assessment of the load-bearing capacity of structural elements.