Mo,CeO_2对镍基合金激光熔覆层组织及性能影响

Effect of Mo and CeO_2 on Microstructure and Properties of Laser Cladding Nickel-Base Alloy Coatings

在镍基合金中分别添加Mo和CeO2,通过激光熔覆在45CrNi钢表面制备了3种熔覆层。利用X射线衍射仪、扫描电镜、能谱仪和磨粒磨损试验机对熔覆层的显微组织及磨粒磨损性能进行了研究。结果表明:添加Mo的熔覆层主要由γ(Ni,Fe),M23C6,M7C3和CrB等相组成,与原Ni基合金相同,无MC,M6C等新相产生。在镍基合金中添加Mo,改变了显微组织中碳化物的成分和形态,组织韧性改善,熔覆层抗磨粒磨损性能提高。Mo对熔覆层磨粒磨损性能的强化作用优于CeO2的细晶强化。

On the surface of 45CrNi steel, three kinds of coatings have been obtained by laser cladding technique through the adulterating with Mo and CeO2 into the Nickel-base alloys. The microstructures and abrasive wear resistance properties of the above three coatings were studied by X-ray diffraction, scanning electron microcopy （SEM）, energy dispersive spectrometer （EDS） and an abrasive wear tester. The results indicate that the Mo-modified Nickel-base alloy coating is composed of γ phase （Ni,Fe）, M23C6, M7C3 and CrB, as well as the original Nickel-base alloy. The new phase, such as MC, M6C were not observed. The changes of the chemical composition and morphology of the carbides of Mo-modified coating were responsible for the improvement of tenacity and abrasive wear resistance. The effect of Mo on abrasive wear resistance of Laser Cladding Nickel-base Alloy Coating is greater than the grain refining effect of CeO2.