Boron carbide–copper infiltrated cermets
Boron carbide–copper infiltrated cermets
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DOI：
10.1016/j.jssc.2003.02.009
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发表时间：
2004-02
影响因子：
3.3
通讯作者：
S. Tariolle;F. Thévenot;M. Aizenstein;M. Dariel;N. Frumin;N. Frage
中科院分区：
文献类型：
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作者：
S. Tariolle;F. Thévenot;M. Aizenstein;M. Dariel;N. Frumin;N. Frage
用Cu-Si合金对含碳和不含碳的多孔碳化硼预制体进行了渗透。与纯铜相反，Cu-Si合金润湿并渗透多孔预制件。对B-C-Cu-Si系合金的热力学分析表明，合金中Si含量高于15at%时，合金中形成SiC。在较高的Si含量下，与熔体接触的碳化硼的组成也朝向较高的硼含量变化。金相检验证实了这些结论。SiC化合物优先在含有过量碳的预制件中的游离碳颗粒周围形成，并且也在不含任何过量碳的碳化物附近形成。最终，SiC，碳化物和熔体之间反应的产物，形成了一个连续的屏障，阻碍了反应的完成，并解释了由于长时间的热处理而导致的有限的硬度增加。
Porous boron carbide preforms, prepared with and without excess carbon, were infiltrated with a Cu–Si alloy. Contrary to unalloyed copper, the Cu–Si alloy wets and infiltrates the porous preforms. A thermodynamic analysis of the B–C–Cu–Si system indicated that a Si content of the alloy above 15at% leads to the formation of SiC. At higher Si content, the composition of boron carbide in contact with the melt also changes towards higher boron content. Metallographic examination validated these conclusions. The SiC compound forms preferentially around the free carbon particles in preforms containing excess carbon, and also in the vicinity of carbide that did not contain any excess carbon. Eventually, SiC, a product of the reaction between the carbide and the melt, forms a continuous barrier that impedes completion of the reaction and accounts for the limited increase of hardness as a result of lengthy heat treatments.