Research status of additive manufacturing technology used for high temperature titanium alloys and titanium matrix composites
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摘要: 高温钛合金及钛基复合材料因具有比强度高、比刚度高、耐腐蚀、耐高温等优异性能，近几年来受到了广泛的关注。钛基复合材料的力学性能往往与增强相组织有关，增材制造技术的快速凝固可以使颗粒增强钛基复合材料中晶粒细化，力学性能得到提升。本文综述了高温钛合金及钛基复合材料的研究进展，分析了增强相组织对材料力学性能的影响，总结了增材制造技术制备钛基梯度功能材料的应用。通过增材制造技术制备钛基复合材料不仅可以提高复合材料的硬度和强度，还可以提高复合材料的延展性，采用增材制造技术制备高性能钛基复合材料将会成为未来的发展趋势。Abstract: High temperature titanium alloys and titanium matrix composites (TMCs) have attracted the extensive attention in recent years due to the excellent properties, such as high specific strength, high specific stiffness, high corrosion resistance, and high temperature resistance. The mechanical properties of the titanium matrix composites are often related to the reinforcing phase microstructures. The rapid solidification of additive manufacturing technology can refine particles and improve the mechanical properties of the particle-reinforced titanium matrix composites. The research progress of high temperature titanium alloys and titanium matrix composites was reviewed in this paper. The influence of the reinforcing phase on the mechanical properties of the titanium alloys and titanium matrix composites was analyzed, and the application of additive manufacturing technology used for the titanium-based gradient functional materials was summarized. The additive manufacturing technology can not only improve the hardness and strength of the particle-reinforced titanium matrix composites, but also increase the ductility of the composites, which will become the future development trend.
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图 2 增材制造制备钛基复合材料与未加增强相材料硬度
Figure 2. Hardness of TMCs prepared by additive manufacturing and the unreinforced materials
图 3 Ti合金及添加不同质量分数TiB2钛基复合材料的电子背散射衍射形貌和α片层尺寸分析[56]：（a）Ti‒6Al‒4V；（b）0.16%TiB2；（c）1.61%TiB2；（d）3.22%TiB2
Figure 3. Electron backscattered diffraction analysis and α lamella size of Ti alloys and TMCs with the different mass fraction of TiB2[56]: (a) Ti‒6Al‒4V; (b) 0.16%TiB2; (c) 1.61%TiB2; (d) 3.22%TiB2
表 1 航空领域常用高温钛合金牌号及成分
Table 1. Grades and components of the high-temperature titanium alloys
国家 钛合金牌号 服役温度 / ℃ 成分组成（质量分数） / % 美国 Ti6242 450 Ti‒6Al‒2Sn‒4Zr‒2Mo Ti6242s 520 Ti‒6Al‒2Sn‒4Zr‒2Mo‒0.1Si Ti1100 600 Ti‒6Al‒2.75Sn‒4Zr‒0.4Mo‒0.45Si 英国 IMI829 540 Ti‒5Al‒3.5Sn‒3Zr‒0.27Mo‒0.3Si‒1.0Nb IMI834 600 Ti‒5.8Al‒4.0Sn‒3.5Zr‒0.5Mo‒0.35Si‒0.7Nb‒0.06C 俄罗斯 BT18Y 550～600 Ti‒6.8Al‒2.5Sn‒4Zr‒0.7Mo‒0.2Si‒1Nb BT36 600 Ti‒6.3Al‒2.2Sn‒3.5Zr‒0.7Mo‒0.15Si‒5W 中国 Ti60 600 Ti‒5.8Al‒4.8Sn‒2Zr‒1Mo‒0.35Si‒0.85Nd Ti600 600 Ti‒6Al‒2.8Sn‒4Zr‒0.5Mo‒0.4Si‒0.1Y Ti65 650 Ti‒5.9Al‒4.0Sn‒3.5Zr‒0.3Mo‒0.4Si‒0.3Nb‒2.0Ta‒1.0W‒0.05C 
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