(1. 北京科技大学 新金属材料国家重点实验室，北京 100083；
2. 北京工业大学 材料学院，北京 100022)
摘 要: 采用8×8网格蜡网制备包埋料型壳，对比研究各微合金元素对Ti-45Al-8Nb合金熔体流动充型性能的影响。结果表明：微量Si、Y、Cr、B、Ni元素的加入能够提高Ti-45Al-8Nb合金的流动性能；而W、Co元素的作用不明显；Mo、V对基体合金的流动性不利。通过铸造模拟软件Procast对比分析，Cr、Ni的加入提高合金过热度，增大了固液相线温度差，提高了熔体的流动性；Si和Y提高合金的抗氧化性，减少熔体与型壳的反应程度，从而提高合金的流动性；B提高熔体流动性的原因归结为其细化作用。
关键字: 高Nb-TiAl合金；铸造；合金化；流动性；Procast模拟
（1. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing,
Beijing 100083, China;
2. School of Materials Science and Engineering, Beijing University of Technology, Beijing 100022, China）
Abstract:Embedded material shell was prepared using wax grid with 8×8 mesh. The effects of micro-alloy elements on the fluidity and mold filling property of Ti-45Al-8Nb melt were studied. The results show that the fluidity and mold filling property of Ti-45Al-8Nb melt are improved by Si, Y, Cr, B, Ni addition. However, W and Co show no apparent effectiveness. Mo and V have a negative impact on the fluidity. Procast, the casting simulation software was used to analyze the reasons. Cr and Ni can reduce the melting point and increase the superheat temperature, so, the fluidity of the melt is increased. Si and Y improve the oxidation resistance of alloy and reduce the reaction between melt and shell, therefore, the fluidity of the alloy enhances. B improves the fluidity property attributed to its refinement.
Key words: high Nb-containing TiAl alloy; casting; alloying; fluidity; Procast simulation
