Sổ tay ma sát và Nano P12 pptx

... 12.2.1.3 Domain Structure in a Thin-Film Head Magnetic materials are composed of individual domains with local magnetization which is equal to the saturation magnetization of the materials. Magnetic ... Magnetic domain structure is defined by minimizing the total magnetic energy of the domain wall, the magnetic anisotropy, and the magnetostriction energy. In general, when the size of the ma...

Ngày tải lên: 04/07/2014, 07:20

... elastic effects in any measuring apparatus and in the materials involved that make measurement of the force distribution at the interface difficult. Materials can change mechanical properties as a result ... as hardness, ductility, defect formation, plasticity, strain hardening, and creep must be considered. Surface properties may be altered just by contact with the counterface material (Carpi...

Ngày tải lên: 04/07/2014, 07:20

... be deflected (normal force signal). Images taken in the constant-height mode show no contrast in the topographic image, in this case all information is in the normal force image. Images taken in ... the other, the decrease of the normal force for increasing tip–sample distance, normal and lateral forces are calculated as Therefore, minima and maxima of the normal and lateral forces are shifted...

Ngày tải lên: 04/07/2014, 07:20

... properties of mating components dominate the tribological perfor- mance. In micro/nanotribology, measurements are made on components, at least one of the mating components, with relatively small mass ... 1989; Mamin et al., 1990; Utsugi, 1990; Hosoki et al., 1992; Kobayashi et al., 1993), and nanomachining (Parkinson, 1990). AFMs have also been used for nanofabrication (Maju...

Ngày tải lên: 04/07/2014, 07:20

... the mass to 0.1 µg. This lumped mass m eff , however, is smaller than the real mass m, by a factor that depends on the geometry of the cantilever. A good rule of thumb says that the effective mass ... the real mass. Today, micro-machined cantilevers are commercially available and are used almost exclusively. 2.2.4 Materials and Geometry Cantilevers have been made from a whole range of materia...

Ngày tải lên: 04/07/2014, 07:20

... be resolved. One may ask how is it that, under increasing load, smaller asperities under plastic deformation may merge to form a larger spot which can be under elastic deformation. A qualitative answer ... be approximated by an ellipse. Then the x- and the y-directions correspond to the major and the minor axes of the ellipse. The assumption made in this model is that the major and minor axes...

Ngày tải lên: 04/07/2014, 07:20

... water (≈80). 5.3.4 Electromagnetic Forces There are three classes of magnetism — diamagnetism, paramagnetism, and ferromagnetism. In paramag- netic and diamagnetic materials, electron spins are ... was written. For example, many simulations neglect the fact that electrons have spin, so that normally magnetic materials may not have magnetic moments in a simulation. Magnetic forces can overpowe...

Ngày tải lên: 04/07/2014, 07:20

... scanned at various normal loads (ranging from 1 to 100 µN) for a selected number of cycles. For nanofabrication/nanomachining, the nanoscratching operation is extended. For nanoindentation hardness ... 1993), and nanomachining (Parkinson, 1990). AFMs have also been used for nanofabrication (Majumdar et al., 1992; Bhushan et al., 1994a,c; Bhushan, 1995a,b, 1998a,b; Tsau et al., 1994) and nanom...

Ngày tải lên: 04/07/2014, 07:20

... microscopy. 8.2 Nanodeformation, Adhesive Forces, and Molecular Conformation Nanodeformation behavior of the bonded lubricant was studied using atomic force microscopy (AFM) by Blackman et al. ... Atomic Force/Friction Force Microscopy Bharat Bhushan 8.1 Introduction 8.2 Nanodeformation, Adhesive Forces, and Molecular Conformation 8.3 Boundary Lubrication Studies Liquid Lubric...

Ngày tải lên: 04/07/2014, 07:20

... component. This may or may not be superimposed on a monotonic repulsion (Figure 9.9) due to image interactions (Jönsson and Wennerström, 1983), structural or H-bonding interactions (Marcelja and ... mismatching effects. As shown by the experiments, within the last 1 or 2 nm, these effects can alter the adhesive minima at a given separation by a factor of two. The force barriers, or maxima, .....

Ngày tải lên: 04/07/2014, 07:20