稀土对真空熔结镍基金属陶瓷复合层成分和硬度分布的影响

研究了真空熔结镍基金属陶瓷复合涂层纵截面的微观组织形态、化学组成、相结构，及合金元素与显微硬度的分布特征。结果表明：稀土（Ce＋La）消除了Ni60＋WC涂层中的针状相，改变了析出相的分布形态，增加了熔合带的宽度。稀土改变了涂层的化学组成，提高了Ni、Cr、Si和W的含量；降低了Fe的含量。Ni60＋WC＋RE涂层还析出了新的Cr3Ni5Si2相。两种Ni60＋WC复合涂层显微硬度的最大值都出现在距涂层表面的0．2mm处，稀土明显地提高了复合涂层的显微硬度。

Effect of Rare Earth on Component and Microhardness Distribution of Vacuum Fusion Sintered Ni-Based Metal-Ceramic Composite Coating

The microstructure,chemical composition,phase structure,and distributing characteristics of alloy elements and microhardness of vacuum fusion sintered Ni-based metal-ceramic composite coatings were studied.The results show that the addition of rare earth elements(Ce+La) changes the morphology and distribution of the precipitated phases,and increases the fusion zone width of interface and the needle phase disappears in the Ni60+WC cating.Rare earth elements change the chemical composition of coating,and increase the contents of Ni,Cr,Si and W of coating and decrease Fe content of the coating.New phase Cr_3Ni_5Si_2 is precipitated form Ni60+WC+RE coating.Microhardness values of two kinds of coating reach their maximum values at 0.2mm from the coating surface,and rare earth elements (Ce+La) can apparently enhance the microhardness of Ni-based metal-ceramic composite coating.