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Silicide coating was prepared on electro-deposited nickel layer by the slurry pack cementation process on copper matrix at 1173 K for 12 h using SiO_2 as Si source,pure Al powder as reducer,a dual activator of NaF+NH_4Cl and albumen(egg white)as cohesive agent.Microstructure,properties and siliconizing mechanism of silicide coating were discussed.The experimental results show that the silicide coating with 220μm thickness is mainly composed of a Ni_2Si phase and a small amount of Ni_(31)Si_(12) phase.Its mean microhardness(HV 790)is ten times than that of copper substrate (HV 70).The coefficient of friction decreases from 0.8 of pure copper to about 0.3 of the siliconzed sample.SiF_2,SiCl_2 and SiCl_3 are responsible for the transportation and deposition of Si during the slurry pack cementation process.