金属磨损自修复层的X光电子能谱研究

金属磨损自修复剂可在机器运行状态下不解体地原位修复零件磨损表面。铁路内燃机车应用修复剂在中修约(300 000 km)时解体观测表明，柴油机缸套表面生成自修复保护层，缸套和活塞环均无磨耗。采用扫描电子显微镜(SEM)和纳米硬度计表征自修复保护层的形貌和力学性能，X射线光电子能谱(XPS)技术分析自修复保护层的表面化学组成，应用氩离子溅射方法对自修复保护层的化学组成进行深度剖析，研究自修复保护层中主要组分的纵向分布特性。实验结果表明：保护层厚度达8～10 μm，表面纳米硬度比铸铁基体提高1倍，保护层主要由Fe，C和O三种元素组成，它们构成Fe₃O₄和Fe₃C两种化学态。初步推测自修复保护层是修复剂发生力化学活化并与磨损表面之间发生力化学反应生成的。

XPS Characterization of Auto-Reconditioning Layer on Worn Metal Surfaces

An auto-reconditioner package for in situ reconditioning of worn surfaces of machinery parts under normal running was applied to diesel engines of DF locomotives. A reconditioning layer was generated on the cylinder bore after running a mileage of 300,000 km, and no wear was measured for the piston rings and cylinder bores. Evaluations with SEM, nanohardness tester and XPS indicated that the protective layer assumed a thickness of 8-10 microm, a nano-hardness twice as high as that of the cast iron substrate, and a main elemental composition of Fe, O and C corresponding to the existence of Fe3O4 and Fe3C. A possible formation mechanism of the protective layer was suggested based on the mechanochemical activation of metal surfaces and the catalytic activation of the auto-reconditioner molecules.