Elasto-plastic deformation analysis of rotating disc beyond its limit speed

The development of new materials is leading to the production of more speedy rotating discs. The knowledge of elastic–plastic response of rotating discs may be helpful in the manufacture and development of discs. Using two types of material properties including the Elastic Perfectly Plastic (EPP) and Ramberg–Osgood models, the concepts of failure and limit speed of discs are studied. Different steps of solution consisting of discretization and imaging process are expounded. The effect of different parameters including the cross section profiles and material properties upon the limit speed is investigated. The study includes the analysis of the post failure mechanical behavior of the discs. It is seen that the hardening exponent in the Ramberg–Osgood equation controls the sensitivity of disc expansion relative to the increase of its rotational speed. For the special case of a disc with uniform thickness, the index of sensitivity is connected to the exponent of the Ramberg–Osgood equation.

► The paper emphasizes the importance of the plastic limit speed of the rotating discs.
► Two material models of elastic perfectly plastic (EPP) and Ramberg-Osgood are used in the analyses.
► The analysis shows the difference between the material models in the prediction of rotating disc plastic failure.
► Among the discs with similar thickness at the internal and external radii, the limit speed of a disc with linear cross section is the most.
►  Based on Ramberg-Osgood model, at velocities higher than the limit speed, the expansion of disc is not abrupt.