本文研究了烧结助剂Ｎｉ对Ｃ－Ｂ_４Ｃ－ＳｉＣ复合材料显微结构与性能的影响．Ｘ射线衍射表明Ｎｉ在烧结温度下与ＳｉＣ，Ｂ_４Ｃ人发生反应在晶界生成Ｎｉ_（４．６）Ｓｉ_２Ｂ，并产生液相，有效地促进了Ｃ－Ｂ_４Ｃ－ＳｉＣ复合材料的烧结，抑制了晶粒的长大，使复合材料密度与强度大幅度地增加，电阻率下降；同时Ｎｉ_（４．６）Ｓｉ_２Ｂ在氧化时生成致密的２ＮｉＯ·Ｂ_２Ｏ_３，包裹了易氧化的Ｂ_４Ｃ和Ｃ，有效地防止了复合材料的氧化，从而大大提高了制品的抗氧化性能．
The effect of additive Ni on the microstructure and properties of C-B_4C-SiC composite was studied. X-ray diffraction indicates that Ni reacts along the grain boundaries with SiC, B_4C to form liguid Ni_(4.6)Si_2B. Thus the effective sintering may be accelerated and the growth of grain was controlled. Consequently, the density and strength of the composite increase markedly, and the electric resistance decreases a little. On the other hand, when the composite was oxidized, Ni_(4.6)Si_2 B was first oxidized to form the dense 2NiO·B_2O_3 which wrapts up carbon and B_4C particles, and makes them difficult to oxidize. So the oxidation resistance of the composite increases greatly. (Correspondent: HUANG Qizhong, associate prpfessor Institute of Powder Metallurgy Research, Central South University of Technology, Changsha 410083)
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| [6] | 李杰．碳素,1993 |
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