A Method to Predict the Durability of Friction Materials Applied on Drum Brakes Based on the Dissipation of Braking Energy

It is becoming more and more common to apply simulation tools with the purpose of reducing the development time of new products and processes in the industry. Researchers have been engaged in developing simulation models based on the energy dissipation to predict the behavior of materials submitted to wear processes. From the characterization of a friction material applied to drum brakes, a method was developed to predict its durability from the energy dissipated in events of braking. For this, it was necessary to develop and apply the Wear Damage Accumulation Rule. The concept behind this rule was based on the Palmgren–Miner damage linear accumulation rule, applied to predict the fatigue response of structural components. For the characterization of the friction material, scale wear bench tests, where specimens were cycled at different intensities of normal load and temperatures, were performed. The energy dissipated in the brakes of a commercial vehicle equipped with the same friction material was obtained along a typical route using adequate equipment. The Wear Damage Accumulation Rule was applied to predict its life. The result was compared to the prediction of its durability obtained by a traditional method applied by the industry. The results obtained by both methods were similar, indicating that the proposed method has the potential for practical application. From the validation of the method presented in this work, new simulation tools could be created and developed to make the process of development of friction materials faster and less expensive for the automotive industry.在工业领域，借助仿真工具以缩短新产品与新工艺的开发周期已愈发普遍。研究人员一直致力于基于能量耗散原理开发仿真模型，以预测材料在磨损过程中的行为表现。针对一款应用于鼓式制动器（drum brakes）的摩擦材料的表征工作，科研人员开发了一种可通过制动过程中耗散的能量来预测其耐久性的方法。为此，需开发并应用磨损损伤累积法则（Wear Damage Accumulation Rule）。该法则的核心概念基于用于预测结构构件疲劳响应的帕尔姆格伦-迈纳（Palmgren–Miner）线性损伤累积法则。为表征该摩擦材料，研究人员开展了规模化台架磨损试验：让试样在不同法向载荷强度与温度条件下进行循环测试。借助配套设备，沿典型行驶路线采集了搭载同款摩擦材料的商用车辆制动器的耗散能量数据。将磨损损伤累积法则用于预测其使用寿命，并将该结果与行业传统方法得到的耐久性预测结果进行对比。两种方法所得结果相近，表明所提出的方法具备实际应用潜力。通过本研究提出的方法的验证，可进一步开发新型仿真工具，以加快汽车行业摩擦材料的开发进程并降低其开发成本。