钛合金表面纳米氧化铈增强MCrAlY熔覆涂层组织

采用激光熔覆技术在钛合金表面制备了纳米氧化铈增强MCr Al Y涂层。利用SEM、OM和XRD等手段,分析了其微观组织和相组成,并与未加纳米氧化铈的涂层进行了对比。结果表明,添加纳米氧化铈后,涂层形状由激光熔覆典型的双弧状转变为扁平状,稀释率由57.9%下降为36.3%,而涂层组成相则基本未发生变化;同时,熔覆层中以树枝状析出的β-Ti变短变小,胞状组织Ni3(Al,Ti)的成分更加均匀,裂纹和孔洞等缺陷被消除;此外,尽管稀释率在下降但其过渡区和平面晶区宽度却有所增大。

Microstructure of CeO2 Nanoparticles Reinforced MCrAlY Cladded Coatings on Titanium Alloy

CeO2 nanoparticles reinforced MCrAlY coatings were prepared on titanium alloy by laser cladding technology. Microstructures and phase structures of the coatings were characterized by SEM, OM and XRD, and they were compared with the coating without nano-CeO2p. Results indicate that the morphology of the coating changes from the double-arcing shape to the tabular shape after adding nano-CeO2p, which is a typical morphology of laser cladding coatings. The dilution ration decreases from 57.9% to 36.3%. However, the phases barely change. Meanwhile, the b-Ti phase with a dendritic pattern in cladding layer becomes shorter and smaller, the composition of cell-shaped Ni3(Al,Ti) more uniform, and cracks and porosities are also eliminated. Moreover, the width of bonding zone and planar crystal zone is increased, though the dilution ration decreases