Brake friction materials (BFMs) are designed to have low wear rate under different conditions of contact pressure, temperature, and sliding velocity. The conditions to ensure a low wear rate (i.e., a moderate wear regime) between the disc and the BFM are not well established. The present article aims to enhance the comprehension about the wear regimes for BFMs. For this purpose, a commercial BFM was slid against a gray cast iron rotor (disc). Tests were performed under different sliding velocities and with both increasing and decreasing steps of pressure levels. Tribofilm formed on the disc's surface and BFM's wear were monitored during the tests. It was possible to conclude that the previous condition of the surface of the disc, with respect to the presence or absence of tribofilm, affects the required conditions for the transition in the wear regime. The removal of tribofilm on the surface of the disc was affected by high contact pressures and high sliding velocities. Those conditions led to a severe wear regime with a destruction of contact plateaus and an increase in friction and BFM's wear.

中文翻译：

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制动摩擦材料磨损状态转变的实验研究

制动摩擦材料 (BFM) 旨在在不同的接触压力、温度和滑动速度条件下具有低磨损率。确保盘和 BFM 之间的低磨损率（即中等磨损状态）的条件还没有很好地建立。本文旨在增强对 BFM 磨损机制的理解。为此，将商用 BFM 靠在灰铸铁转子（盘）上滑动。测试是在不同的滑动速度和压力水平的增加和减少步骤下进行的。在测试过程中监测了圆盘表面形成的摩擦膜和 BFM 的磨损。可以得出结论，盘表面的先前条件，关于摩擦膜的存在或不存在，影响磨损状态过渡所需的条件。圆盘表面摩擦膜的去除受到高接触压力和高滑动速度的影响。这些条件导致严重的磨损状态，接触平台被破坏，摩擦和 BFM 磨损增加。