JpGU-AGU Joint Meeting 2020

Presentation information

[J] Oral

S (Solid Earth Sciences ) » S-CG Complex & General

[S-CG69] Rheology, fracture and friction in Earth and planetary sciences

convener:Miki Tasaka(Shizuoka University), Osamu Kuwano(Japan Agency for Marine-Earth Science and Technology), Ichiko Shimizu(Division of Earth and Planetary Sciences, Graduate School of Science, Kyoto University), Shintaro Azuma(Department of Earth and Planetary Sciences, School of Science, Tokyo Institute of Technology)

[SCG69-06] A statistical mechanical model of magnetic friction obeying the Dieterich-Ruina law

*Hisato Komatsu1 (1.National Institute for Materials Science)

Keywords:friction, magnetic materials, statistical mechanics

Magnetic friction, the magnetic force caused by the magnetic interaction between materials, is studied in recent years. In these studies, several types of statistical mechanical models are proposed so far, and the relation between the magnetic friction F and the velocity between solid surfaces v shows various behaviors depending on the models. Some of them obey the Amontons-Coulomb's law(Kadau et.al. 2008), another types obey the Stokes' law(Magiera et.al. 2009), and the other shows the crossover between these two laws(Magiera et.al. 2011). These studies aim not only to investivgate the friction of magnetic materials, but also to understand the microscopic mechanism of friction itself. However, there is no previously proposed model which obey the Dieterich-Ruina's law, the widely-known empirical modification of the Amontons-Coulomb's law.
We propose a new model of magnetic friction and investigate the F-v relation at the steady state by numerical simulation(Komatsu 2019). This model is composed of two square lattice adjacent to each other, and the external force is imposed on one of them. The magnetic interaction behave as a kind of "potential barrier" which prevent the motion of the lattice. We consider two types of the surface of the upper lattice: the flat and the rough ones.
The behavior of this model is classified into two domains, which we refer to as domains I and II. In domain II, the external force is dominant compared with other forces, whereas in the domain I, the the velocity of the lattice is suppressed by the magnetic interaction and obeys the Dieterich-Ruina law. This characteristic property can be observed regardless of whether the surface is smooth or rough.