Effect of Mo and Si on morphology and volume fraction of eutectic in Nb–Si–Mo alloys
Effect of Mo and Si on morphology and volume fraction of eutectic in Nb–Si–Mo alloys
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DOI：
10.1016/j.msea.2006.12.023
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发表时间：
2007-05
期刊：
影响因子：
6.4
通讯作者：
K. Chattopadhyay;R. Sinha;R. Mitra;K. Ray
中科院分区：
文献类型：
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作者：
K. Chattopadhyay;R. Sinha;R. Mitra;K. Ray
本文研究了具有过共晶（Nb-19 Si-5 Mo，Nb-18 Si-26 Mo）和亚共晶（Nb-13 Si-4 Mo，Nb-12 Si-15 Mo）成分的三元Nb-Si-Mo合金的共晶形貌。这些材料中的共晶由Nb固溶体和Nb_5Si_3的混合物组成，具有层状或非层状形貌。在Si含量相近的情况下，亚共晶合金中非片层共晶的体积分数随Mo含量的增加而增加。而Mo含量对过共晶合金的非片层共晶含量影响不大。具有较高Si浓度的过共晶组合物显示出比亚共晶组合物中发现的大得多的非层状共晶体积分数。三元Nb-Si-Mo合金在凝固过程中的过冷行为与其组成有关，共晶的层片状或非层片状特征有助于解释某些结构-性能关系。
The eutectic morphology of ternary Nb–Si–Mo alloys with hypereutectic (Nb–19Si–5Mo, and Nb–18Si–26Mo) and hypoeutectic (Nb–13Si–4Mo, and Nb–12Si–15Mo) compositions has been examined. The eutectic in these materials has been found to consist of a mixture of Nb solid solution and Nb5Si3with lamellar or non-lamellar morphology. For similar concentration of Si, the volume fraction of non-lamellar eutectic in the hypoeutectic alloys increases with Mo content. However, the concentration of Mo has little effect on the non-lamellar eutectic content of hypereutectic alloys. Hypereutectic compositions, having higher concentration of Si, show a much larger volume fraction of non-lamellar eutectic compared to that found in the hypoeutectic compositions. The lamellar or non-lamellar character of the eutectic is attributed to the composition-dependent under-cooling behaviour of the ternary Nb–Si–Mo alloys during solidification and their volume fractions in these alloys assist to explain some of the structure–property relations.