Influence of Braking Conditions on Tribological Performance of Copper-Based Powder Metallurgical Braking Material
Influence of Braking Conditions on Tribological Performance of Copper-Based Powder Metallurgical Braking Material
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DOI：
10.1007/s11665-018-3537-x
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发表时间：
2018-07
影响因子：
2.3
通讯作者：
Xin Zhang;Yongzheng Zhang;S. Du;T. He;Zhenghai Yang
中科院分区：
文献类型：
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作者：
Xin Zhang;Yongzheng Zhang;S. Du;T. He;Zhenghai Yang
高速运输工具的实际应用需要耐用和有效的摩擦材料。本文采用放电等离子烧结法制备了一种铜基粉末冶金摩擦材料，并对其在不同制动工况下的摩擦学性能进行了研究。利用惯性制动试验台和温度测量仪，在两种初速度（28、69 m/s）和三种接触压力（0.4、0.6和0.8 MPa）下，测试了材料在制动过程中的平均摩擦系数、瞬时摩擦系数和摩擦表面附近的温度。相应地计算了材料的磨损率。结果表明，在相同的压力下，高速时的平均摩擦系数和磨损率小于低速时的平均摩擦系数和磨损率。在高试验速度下，高摩擦温度导致制动过程达到一定阶段时瞬时摩擦系数明显下降。通过对摩擦表面形貌的分析，发现在高速下由于氧化膜的形成，表面的粘着磨损有所降低，随着压力的增加，表面的氧化磨损逐渐增加。
High-speed transportation tools demand durable and effective friction materials for practical applications. In this work, we developed a copper-based powder metallurgical friction material via spark plasma sintering, and studied its tribological performances subjected to different braking conditions. Using inertial braking test bench and temperature measuring instrument, average friction coefficient, instantaneous friction coefficient and temperature near friction surface of the material in braking process were tested at two initial speeds (28, 69 m/s) and three contact pressures (0.4, 0.6 and 0.8 MPa). The wear rate of materials was calculated accordingly. Results show that under the same exerted pressure, the average friction coefficient and wear rate at the high speed are smaller than those at the low speed. At the high test speed, the high friction temperature leads to an obvious decrease in instantaneous friction coefficient when the braking process reaches a certain stage. Based on the friction surface morphology analysis, the adhesive wear on the surface has been reduced because of the formation of oxide films at the high speed and surface oxidation wear gradually increases as the pressure increases.