纳米SiCp增强NiCoCrAlY涂层的组织和抗氧化性能

为了研究纳米SiCp对NiCoCrAlY涂层的组织和抗氧化性能的影响,采用激光熔覆技术在镍基高温合金表面制备了4种不同含量纳米SiCp增强的NiCoCrAlY熔覆涂层,考察了它们的组织及其在1050℃下的等温氧化行为,并初步分析了纳米SiCp的影响机制.结果表明,加入纳米SiCp涂层的组织和抗氧化性能较未加纳米颗粒的涂层均得到了不同程度的改善.其中,添加质量分数1%的纳米SiCp对涂层组织和抗氧化性能的改善作用最为显著.纳米SiCp的加入,不仅改变了界面处的结晶形态,而且细化了熔覆层的组织.熔覆层组织的细化对提高涂层的抗氧化性能有着积极的作用.

Microstructure and oxidation resistance of nanometer SiC particles reinforced NiCoCrAlY coatings

To study the effect of nanometer SiC particles(nano-SiCp) on microstructure and oxidation resistance of NiCoCrAlY coating,four kinds of NiCoCrAlY coatings with different contents of nano-SiCp were prepared on the surface of a Ni-based superalloy using laser cladding technology,and their microstructure and isothermal oxidation behaviors at 1050 °C were investigated.The influencing mechanisms of nano-SiCp were primarily discussed.The results show that the microstructure and oxidation resistance of the coatings with nano-SiCp were incoordinately improved compared with those of the coating without nanometer particles,in which the coating with 1.0 %(mass fraction) nano-SiCp displays the best performance.With the addition of nano-SiCp,not only the crystal habit of the bonding interface between coating and substrate was improved,but also the microstructure of cladding layer was refined.The refinement of cladding layer microstructure plays a very positive role in improving the oxidation resistance of the NiCoCrAlY coatings.