氩气预热处理对Ni－B_4C－RE复合镀层高温氧化特性的影响

Effect of Pre-Heat Treatment in Argon on the High Temperature Oxidation Characteristics of Ni-B_4C-RE Electrodeposits in Air

本文系统地研究了在氩气中预热处理对电沉积Ｎｉ－Ｂ_４－ＲＥ复合镀层在８００℃大气中氧化特性的影响。实验证明，经氩气预热处理，镀层中原Ｂ_４Ｃ微粒逐渐分解、消失，形成了Ｎｉ_３Ｂ新相。这种镀层再经氧化，能生成抗氧化能力较强的均相Ｎｉ_３Ｂ_２Ｏ_６氧化膜。稀土加入镀层后，在氩气预热处理过程中，能促进新相的生成，从而进一步提高了镀层抗高温氧化能力。

n this papor,the oxidation characteristics of Ni-B_4C-RE electredepo8its which carried on pre-heattrcatment in argon at 800℃ in air have been systematically studied. Exporiments shown that after heattrcatment in argon,the initial B_4C particles in deposits were gradually decomposed and eliminated, while thenew phase Ni_3B had formed. During these deporits were subjected to oxidation,more anti oxidized and ho-mogeneous oxide scale Ni_3B_2O_6 could be produced. The rare earth might promote the formation of newphase Ni_3B in course of heat treatment,which further icreased the oxidation resistance of depeits.