(南京工程學(xué)院 材料工程學(xué)院,南京 211167)
摘 要: 采用漿料包滲法,以SiO2粉為滲Si源,純Al粉為還原劑,NH4Cl作為活化劑,Al2O3為惰性添加劑,蛋白質(zhì)(雞蛋清)為粘結(jié)劑,在Cu表面預(yù)先鍍Ni,隨后表面漿料包滲Si制備滲層。研究CeO2氧化物對滲Si層組織和氧化性能影響。結(jié)果表明:滲劑中添加CeO2氧化物后,滲層組織由以Ni31Si12+Ni2Si金屬間化合物為主轉(zhuǎn)變?yōu)橐訬i2Si 為主與NiSi混合的金屬間化合物;滲Si層氧化增質(zhì)由純銅的1/4降低到純銅的1/14,氧化產(chǎn)物為SiO2、Al2O3和少量的NiO,氧化層較致密而且顆粒細小,沒有明顯的裂紋和空洞出現(xiàn),改善了抗高溫氧化性能。
關(guān)鍵字: CeO2;滲Si層;氧化性能;Ni-Si金屬間化合物
(School of Materials Engineering, Nanjing Institute of Technology, Nanjing 211167, China)
Abstract:Using slurry pack cementation mixture with SiO2 as siliconizing source, pure Al powder as reducer, NH4Cl as activator, Al2O3 as inert additive and albumen (egg white) as cohesive agent, the electroplated specimens with a layer of electroplating nickel originally deposited on copper were siliconized to prepare coating. The effects of CeO2 oxides on the microstructures and high temperature oxidation resistance of coating were studied. The results show that the phases of the coating are transformed from Ni31Si12+Ni2Si to Ni2Si+NiSi intermetallics after adding CeO2 oxides. The oxidation mass gain of Si-Al coating is decreased from 1/4 to 1/14 of that of pure copper. The oxide is primarily composed of SiO2, Al2O3 and a small amount of NiO. The oxide layer with smaller grain size is dense without cracks and pores, which improves the high temperature oxidation resistance.
Key words: CeO2; siliconized coating; oxidation resistance; Ni-Si intermetallic compound


