Designed high-friction surfaces—Influence of roughness and deformation of the counter surface

The present paper experimentally investigates the prospects of using surfaces with carefully designed topography to design contacts with a high level of static friction. All tests are run under boundary lubricated conditions. Specifically, very high static coefficients of friction (up to μ ≈ 1.2) are demonstrated for surfaces covered with sharp pyramids. The test surfaces were manufactured using micromechanical techniques based on photolithography and etching of silicon followed by deposition of CVD diamond. The technique results in exceptionally well-defined surface textures with very sharp and durable diamond pyramids. The possibilities of using such surfaces for gripping and various types of coupling applications are discussed in some detail. A good correlation between the achieved results and theoretical predictions of the ploughing component of friction is demonstrated. The technique showed to be very robust with only minor influence of surface roughness and counter surface deformation.