发动机油非磷抗氧、抗磨、减摩添加剂协同研究

降低发动机油的磷含量,提高燃料经济性,延长使用寿命,已是润滑油升级换代大势所趋。为了降低磷的含量,必须减少二烷基二硫代磷酸锌(ZnDDP)的使用,而二烷基二硫代氨基甲酸锌(ZnDDC)是ZnDDP最理想的替代物。为了提高油品的燃料经济性,需要加入有机钼摩擦改进剂,其中,不含硫磷的钼酸酯添加剂,因其良好的减摩保持性,其应用更为突出。为了满足更苛刻的油品高温性能要求,还必须加入烷基化二苯胺类抗氧剂(AD-PA)。因此有必要对非活性钼、ZnDDC和ADPA之间相互作用进行考察。研究表明,在非活性有机钼、ZnDDC、ADPA的三元添加剂体系中,存在着三种相互配合的协同作用:ZnDDC与非活性有机钼的抗磨协同,非活性有机钼与ADPA的抗氧化协同,以及ZnDDC与ADPA的抗氧化协同。利用非活性有机钼、ZnDDC、ADPA的三元非磷协同复合体系(OD 0401),可以大幅度提高油品的抗氧化性能、减摩性能和抗磨性能,这对发展低磷含量的GF-4和GF-5发动机润滑油具有十分积极的意义。利用该协同复合添加剂OD 0401,还可以有效地提高低档发动机油的抗氧化和抗磨性能。

USING LABORATORY TESTS TO PREDICT OXIDATION IN TODAY'S ENGINES

Laboratory bench tests are used to predict lubricant performance in modern engines. The evolution of ASTM(American Society of Testing and Materials) engine Sequence tests and associated laboratory bench tests is reviewed. Several oxidation screening tests are described. Correlation of oxidation screening tests with ASTM Sequence Ⅲ high temperature oxidation engine test is addressed, using both European and ASTM reference oils. Modification of the oxidation screening test methods is attempted in order to improve the correlation as the Sequence Ⅲ test method evolves.