Aperiodic Deformation Occurring as a Result of Thermoplastic Instability of Metals
The author developed a three-dimensional model for the description of fast plastic deformation of metals in the case of cutting. Shear strain occurring as a result of shear stress has a reverse effect on stress, while the temperature of the material is increasing. These counteracting effects may lead to thermomechanic instability, which may result in aperiodic chaotic conditions besides periodic fluctuation due to the non-linear nature of the process. Apart from bifurcation and multi-cycle periodic deformation, the model also describes aperiodic chaotic deformation, which is proven by experimental results.
J. Gyulai and P.J. Szabó
Z. Pálmai, "Aperiodic Deformation Occurring as a Result of Thermoplastic Instability of Metals", Materials Science Forum, Vols. 537-538, pp. 541-548, 2007