Friction forces play a key role in mechanical phenomena occurring on all scales, from the operation of microelectromechanical systems to interplate earthquakes. The study of friction forces is also useful for understanding a large spectrum of physical properties of surfaces. Thanks to the development of nanoscale investigation tools such as scanning probe microscopy, the study of friction and wear phenomena down to the atomic scale is becoming a leading topic within the field of surface physics, and has given rise to the science called nanotribology (Urbakh & Meyer, 2010). We focus here on the anisotropic aspects of nanotribology, related in particular to the surface of crystalline materials such as minerals. Frictional anisotropy is characterized by a dependence of the friction force intensity on the sliding direction and friction force components orthogonal to the sliding direction (Zmitrowicz, 1989). We show how an atomic force microscope can be used to map in two dimensions the frictional anisotropy at the nanoscale and how to carry out data interpretation to unravel the friction– surface structure relationship. As a model system, we analyzed the basal plane of antigorite, which is inherently characterized by marked corrugations, and interpreted the data in terms of constitutive models of anisotropic friction (Campione & Capitani, 2013). The proposed approach unravels unexpected mechanical behaviors which, while consolidating a deeper knowledge of atomic-scale mineral physics, can be now considered the cause of macro-scale phenomena related to seismic anisotropy, slip partitioning, glacial surge, etc.
Campione, M. (2015). Nanotribological analysis of frictional anisotropy of crystalline surfaces and its relationship with surface structure studied through atomic force microscopy. In Il Pianeta Dinamico: sviluppi e prospettive a 100 anni da Wegener (pp.121-121) [10.3301/ROL.2015.131].
Nanotribological analysis of frictional anisotropy of crystalline surfaces and its relationship with surface structure studied through atomic force microscopy
CAMPIONE, MARCELLO
Primo
2015
Abstract
Friction forces play a key role in mechanical phenomena occurring on all scales, from the operation of microelectromechanical systems to interplate earthquakes. The study of friction forces is also useful for understanding a large spectrum of physical properties of surfaces. Thanks to the development of nanoscale investigation tools such as scanning probe microscopy, the study of friction and wear phenomena down to the atomic scale is becoming a leading topic within the field of surface physics, and has given rise to the science called nanotribology (Urbakh & Meyer, 2010). We focus here on the anisotropic aspects of nanotribology, related in particular to the surface of crystalline materials such as minerals. Frictional anisotropy is characterized by a dependence of the friction force intensity on the sliding direction and friction force components orthogonal to the sliding direction (Zmitrowicz, 1989). We show how an atomic force microscope can be used to map in two dimensions the frictional anisotropy at the nanoscale and how to carry out data interpretation to unravel the friction– surface structure relationship. As a model system, we analyzed the basal plane of antigorite, which is inherently characterized by marked corrugations, and interpreted the data in terms of constitutive models of anisotropic friction (Campione & Capitani, 2013). The proposed approach unravels unexpected mechanical behaviors which, while consolidating a deeper knowledge of atomic-scale mineral physics, can be now considered the cause of macro-scale phenomena related to seismic anisotropy, slip partitioning, glacial surge, etc.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.