5:15 PM - 6:30 PM
[SCG46-P12] Relaxation of the frictional force in a statistical mechanical model of magnetic friction
Keywords:friction, magnetic materials, statistical mechanics
Magnetic friction, the frictional force caused by the magnetic interaction between materials, is studied in recent years to investigate the microscopic mechanism of the friction. As part of these studies, we previously proposed a statistical mechanical model of magnetic friction obeying the Dieterich-Ruina law in the steady state with sufficiently weak external force(Komatsu 2019). This law is a well-known empirical law observed in the usual solid surfaces, so our previous study implies that the analogy between the magnetic and usual frictions exists.
In this presentation, we investigate the behavior of the magnetic friction in the non-steady state using a model similar to our previous one. Specifically, we consider a chain moving on the edge of a two-dimensional lattice, and let each lattice point of them have one spin variable interacting with each other. The chain is combined with a spring, and the other edge of the spring moves with a constant veocity v.
We investigate the responce of the frictional force to the sudden change of v by the numerical simulation. If the time scale of the spin relaxation is slower than that of the chain motion, the relaxation of the frictional force is divided into two processes: the sudden change accompanied by that of v called direct process, and the slow relaxation after that called indirect process. This behavior resembles that observed in the usual solid surfaces. In the case of the usual solid surfaces, it is said that these two processes result from the creep motion of the materials. In the case of our model, on the other hand, this behavior is caused by the slow relaxation of the magnetic structure. Hence, the change of the magnetic structure of our model has a similar role to the creep motion of usual solid surfaces.
In this presentation, we investigate the behavior of the magnetic friction in the non-steady state using a model similar to our previous one. Specifically, we consider a chain moving on the edge of a two-dimensional lattice, and let each lattice point of them have one spin variable interacting with each other. The chain is combined with a spring, and the other edge of the spring moves with a constant veocity v.
We investigate the responce of the frictional force to the sudden change of v by the numerical simulation. If the time scale of the spin relaxation is slower than that of the chain motion, the relaxation of the frictional force is divided into two processes: the sudden change accompanied by that of v called direct process, and the slow relaxation after that called indirect process. This behavior resembles that observed in the usual solid surfaces. In the case of the usual solid surfaces, it is said that these two processes result from the creep motion of the materials. In the case of our model, on the other hand, this behavior is caused by the slow relaxation of the magnetic structure. Hence, the change of the magnetic structure of our model has a similar role to the creep motion of usual solid surfaces.