Effect of CeO2 on the microstructure and properties of AlCoCrFeNi2.1 laser cladding coatings

In the process of strengthening the substrate’s surface properties, it is easy to produce cracks or air holes and other defects between the coatings and the substrate, and rare earth elements can improve the microstructure and properties of the metal surface coatings. Using laser cladding(LC) technology, the effect of the addition of rare earth oxides CeO2 on the properties of AlCoCrFeNi2.1 coatings is investigated to find the optimal amount of CeO2 added. AlCoCrFeNi2.1 alloy powder doped with Xwt% (X=0~3) rare-earth oxide CeO2 was clad on the surface of the H13 steel substrate by laser cladding process using RFL-C3000 laser. The macroscopic morphology, microstructure, hardness, and corrosion resistance of specimens were analyzed and studied by optical microscope (OM), scanning electron microscope (SEM), X-ray diffractometer (XRD), hardness tester, and other equipment. The results show that the addition of the appropriate amount of rare earth oxide CeO2 (3%) can effectively reduce the cracks, air holes, and inclusions in the composite layer, and promote grain refinement. The addition of 3 wt.%CeO2 to AlCoCrFeNi2.1 can improve the microstructure uniformity and surface hardness of the coatings, and significantly improve the wear and corrosion resistance of the composite coatings.