Abstract: An article of manufacture comprising: (a) a body at least a portion of which is a multi-phase material (MPM) defining a traction surface; (b) the MPM comprising at least first and second zones comprising first and second materials, M1, M2, respectively, at or near the traction surface, the M1 and M2 having first and second Young moduli respectively, the first and second moduli differing by at least a factor of 3; and (c) wherein each of the second zones has a center, and wherein the second zones have a center-to-center radial distribution function having a peak at between 10 ?m and 10 mm.

Abstract: Resilient members having near-surface architectures including microstructures for controlling friction are provided. A film-terminated array of fibrils having a sharp film/fibril juncture exhibits an unexpectedly large enhancement of adhesion, static friction and sliding friction. The enhancement is provided against rough indenters. A film-terminated array of elongated ridges and valleys unexpectedly exhibits low adhesion, and an unexpectedly large enhancement of sliding friction. The film-terminated ridge/valley design provides an anisotropic structure with direction-dependent frictional properties. The increase in sliding friction force varies as a function of interfibrillar spacing, and corresponds to a mode in which buckling of the terminal film occurs. The near surface architectures may be designed with varying scales and varying parameters to provide performance characteristics tailored to various applications.

Abstract: An article of manufacture comprising: (a) a body at least a portion of which is a multi-phase material (MPM) defining a traction surface; (b) the MPM comprising at least first and second zones comprising first and second materials, M1, M2, respectively, at or near the traction surface, the M1 and M2 having first and second Young moduli respectively, the first and second moduli differing by at least a factor of 3; and (c) wherein each of the second zones has a center, and wherein the second zones have a center-to-center radial distribution function having a peak at between 10 ?m and 10 mm.

Abstract: Resilient members having near-surface architectures including microstructures for controlling friction are provided. A film-terminated array of fibrils having a sharp film/fibril juncture exhibits an unexpectedly large enhancement of adhesion, static friction and sliding friction. The enhancement is provided against so rough indenters. A film-terminated array of elongated ridges and valleys unexpectedly exhibits low adhesion, and an unexpectedly large enhancement of sliding friction. The film-terminated ridge/valley design provides an anisotropic structure with direction-dependent frictional properties. The increase in sliding friction force varies as a function of interfibrillar spacing, and corresponds to a mode is in which buckling of the terminal film occurs. The near surface architectures may be designed with varying scales and varying parameters to provide performance characteristics tailored to various applications.

Abstract: Resilient members having near-surface architectures including microstructures for controlling friction are provided. A film-terminated array of fibrils having a sharp film/fibril juncture exhibits an unexpectedly large enhancement of adhesion, static friction and sliding friction. The enhancement is provided against rough indenters. A film-terminated array of elongated ridges and valleys unexpectedly exhibits low adhesion, and an unexpectedly large enhancement of sliding friction. The film-terminated ridge/valley design provides an anisotropic structure with direction-dependent frictional properties. The increase in sliding friction force varies as a function of interfibrillar spacing, and corresponds to a mode in which buckling of the terminal film occurs. The near surface architectures may be designed with varying scales and varying parameters to provide performance characteristics tailored to various applications.