CeO_2对铁基自润滑轴承材料性能的影响

Effects of CeO_2 on Properties of Iron-based Self-lubricated Bearing Materials

采用粉末冶金法在Fe-C-Cu自润滑轴承材料基体上添加了不同比例的CeO2,研究了CeO2加入量及压坯密度对铁基自润滑轴承材料性能的影响。通过显微组织观察、能谱分析、摩擦表面形貌观察以及滑动轴承模拟试验可知,加入适量CeO2可以活化烧结、改善组织,增大材料的径向压溃强度和表观硬度,减小摩擦系数和磨损量,以及提高力学性能和耐磨性能;加入过量CeO2会使组织中的"条状物"增多、粗化,恶化材料的性能。较高的压坯密度可以提高材料的径向压溃强度和表观硬度,磨损量略微减小或基本不变,摩擦系数有所增大,温升提高,故应针对不同使用要求,合理选择材料的压坯密度,使密度与摩擦性能合理搭配。

The Fe-C-Cu self-lubricated materials with different mass ratios of CeO2 are prepared by powder metallurgy. Effects of CeO2 addition and green density on properties of material are studied. By means of SEM, EDS, microscopy of wear surface and sliding bearing running test, the results show that certain amounts of CeO2 addition can activate the sintering process, refine the grains, improve the dynamic and friction properties, while excessive CeO2 addition leads to strips increasing and coarseming which decrease the properties of materials. In addition, high green density of materials improves the crushing strength and apparent hardness while the wear volume decreases slightly or remains stable, the coefficient of friction and the temperature rise increase a lot. So the green density must be chosen appropriately to match the friction property according to the applied condition.