TY - JOUR A1 - Dmitriev, A.I. A1 - Österle, Werner A1 - Kloß, Heinz T1 - Numerical simulation of typical contact situations of brake friction materials N2 - In the paper, a model typical for contact situations of automotive brakes is established based on the method of movable cellular automata. The processes taking place at local contacts in an automotive brake system are analysed. Based on microscopic and micro-analytical observations, the following contact situations were simulated: (i) a couple of ferritic steel against pearlitic steel, both covered by an oxide layer mixed with graphite nanoparticles and (ii) the same situation but without oxide layers. The results of calculated mean coefficients of friction of the oxide-on-oxide contact correspond well to expected values for a real braking system, whereas steel-on-steel contact are twice as high. This allows one to make some conclusions; for example, oxide formation will take place more quickly than friction layer elimination, and finally this is responsible for the stabilisation of the coefficient of friction. KW - Friction KW - Primary contact KW - Automotive brake system KW - Numerical simulation KW - Method of movable cellular automata PY - 2008 U6 - https://doi.org/10.1016/j.triboint.2007.04.001 SN - 0301-679X VL - 41 IS - 1 SP - 1 EP - 8 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-15841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dmitriev, A. I. A1 - Österle, Werner T1 - Sliding simulation of automotive brake primary contact with variable amounts of copper and graphite nanoparticles N2 - Copper is one of the most important components in brake pads and its amount can reach up to 14%. In spite of a number of positive features copper usage in brake pad formulations has recently become the subject of considerable discussions, primarily due to concerns about potential risks related to environmental impacts of copper particles. So, for developing new pad formulations with possible replacements of copper content, it is very important to understand the functionality of copper additions to brake friction materials. In the paper theoretical investigation of the role of copper as a pad ingredient was carried out on the basis of modelling by the method of movable cellular automata (MCA). In the study the concentration of copper particles in a Fe3O4-matrix was varied. The sliding simulations were performed while assuming material properties at 500 degrees C in order to assess the beneficial role of copper during severe braking conditions corresponding to fading cycles during dynamometer testing. T2 - International Conference on Advanced Materials with Hierarchical Structure for New Technologies and Reliable Structures CY - Tomsk, Russia DA - 19.09.2016 KW - Polymer matrix composite KW - Silica nanoparticles KW - Friction KW - Wear PY - 2016 U6 - https://doi.org/10.1063/1.4966337 VL - 1783 SP - 020044-1 EP - 020044-4 AN - OPUS4-38933 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -