5:15 PM - 6:30 PM
[SCG63-P15] Frictional Characteristics of Cleaved Mica Surfaces and Theoretical Considerations of the Frictional Mechanism
Keywords:Dependence of normal stress, Double shear test, Layered minerals, Water, First-principles calculations
Interlayer bonding energy (ILBE) of these layered minerals has been believed to have a linear relationship with the friction coefficients . However, this linear relationship was not confirmed by recent shear experiments [2,3]. Reliable ILBEs derived by the first-principles electronic state calculations  revealed that the linear relationship is unclear for both experimental friction coefficients [1,2]. In this study, we tried to understand a factor controlling the friction of mica and clay minerals instead of the ILBE.
Double shear test of cleaved mica surfaces was conducted as a function of normal stress ranging from 5 to 60 MPa. The friction coefficient decreased with increasing normal stress. This behavior has been observed for the powder of mica and clay minerals , however, the mechanism is unclear. In this talk, we discuss the mechanism by comparing our results with previous powder experiments and by using the first-principles electronic state calculations.
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