To explain the observations, we derive the local stability condition of ICWs based on kinetic theory, with pickup ions treated as a cold-ring distribution and background thermal ions treated as a Maxwellian distribution.
These values were estimated from the local stability theory by assuming a cold-ring distribution for the pickup ions and a Maxwellian distribution for the background thermal ions (note that (T_) values obtained in this paper are calculated from the axisymmetric rotating plasma equilibrium model and its values are only in qualitative agreement with the observed data).
Based on the actual working condition of a vertical cold ring-rolling mill rolling a groove ball ring, a mathematical model for the following guide roller motion is established.
The process has potential to allow flexible near-net-shape forming of both hot and cold rings, and has been assessed by experiments on commercial cold ring rolling machines, a physical simulation using wax rings, and two finite element models.
Just chewing on a cold teething ring or other teething toy (or even a cold washcloth) can make a miserable baby feel better — as can a dose of acetaminophen or ibuprofen (for children under 2, it's best to check with the doctor for the correct dose for the child's weight).
Asked last week about Woods's chances for a return to form, Johnson answered respectfully, but his response resonated with the cold ring of reality.
The obtained results thoroughly reveal the influence laws of the sizes of forming rolls on the average spread, fishtail coefficient, degree of inhomogeneous deformation and force and power parameters etc not only provide an important basis for design of the forming rolls and optimization of cold ring rolling process, but also reveal the plastic deformation mechanism of cold ring rolling.
During cold ring rolling processes, the material properties of the ring blank have a significant effect on the quality of the deformed ring and the determination of forming parameters.
So the size effect of forming rolls on cold ring rolling was investigated by three-dimensional dynamic explicit FEM under ABAQUS environment.
The achievements of this study provide an important guide for selecting the material of the ring blank and determining the forming parameters according to the material properties of ring blank, and are very significant for the optimum design and precision control of the cold ring rolling process.
