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用球盘式摩擦试验机及原子力显微镜在大气中常温下对YBa2Cu3O7(YBCO)高温超导试样的宏观和微观摩擦学特性进行了研究,并与Cu基固体润滑复合材料进行比较。结果表明:对于Cu基复合材料,固体润滑剂含量不足将使摩擦系数增大,含量过高将导致磨损增大,含40%固体润滑剂的4060Cu在几种载荷和速度下都表现出很低的摩擦和磨损,而YBa2Cu3O7的摩擦系数与4060Cu相似,磨损率却只有其1/2。XRD及TEM的检测结果表明:YBa2Cu3O7结构中的CuO层结合较弱,在剪切应力的作用下易滑移,对外表现出较低的摩擦。基体中含Y2O3较多的YBa2Cu3O7相阻碍位错滑移,强化基体,使其耐磨性能大幅提高。用粉末熔化法制备的样品中Y2O3颗粒更细小、弥散,其耐磨性更好。
The macroscopic and microscopic tribological properties of YBa2Cu3O7 (YBCO) high temperature superconducting samples were investigated at room temperature using ball-and-disk friction tester and atomic force microscopy and compared with Cu-based solid lubricating composites. The results show that for Cu-based composites, the insufficient content of solid lubricant will increase the friction coefficient. If the content is too high, the wear will increase. 4060Cu containing 40% solid lubricant shows low Of the friction and wear, and YBa2Cu3O7 friction coefficient similar to 4060Cu, the wear rate is only 1/2. The results of XRD and TEM show that the CuO layer in YBa2Cu3O7 structure is weakly bonded and slips easily under the action of shear stress and shows low friction with the outside. The YBa2Cu3O7 phase containing more Y2O3 in the matrix obstructs the sliding of dislocations and strengthens the matrix so that its wear resistance can be greatly improved. Y2O3 particles prepared by the powder melting method are finer and more dispersed, and their wear resistance is better.