Microstructure of laser cladding multi-layer Nb-Si-Ti

被引：3
|
作者：
机构：
[1] Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education, Northeastern University, Shenyang
来源：
Liang, Jing | 1710年 / Northeast University卷 / 35期
关键词：
Composition design; Microstructure; Multi-layer laser cladding; Nb-Si-Ti; Niobium silicide based in-situ composites;
D O I：
10.3969/j.issn.1005-3026.2014.12.009
中图分类号：
学科分类号：
摘要：
The microstructure and composition design of the niobium silicide based composites which prepared by direct laser fabrication based on multi-layer laser cladding through optimizing laser scanning parameters and adjusting the composition ratio of the mixed element powders were investigated. Element powders mixture Nb-18Si-24Ti (at.%) was prepasted on a substrate of Ti-6Al-4V and scanned by a 500 W pulsed Nd:YAG laser. Four-layer specimens were fabricated under the optimized laser processing parameters with electric current of 225A, laser scanning speed of 3.0 mm/s, pulsed frequency of 15Hz, defocus length of 15 mm. Microstructures and phases of the prepared specimens were analyzed by OM, SEM and XRD, respectively. Results showed that Nb5Si3, Nb3Si and Nbss are formed in the multilayer laser cladding coatings. With the increase of the number of layers, the Nb and Si contents increase gradually, tiny dendrites are found in the layer near the substrate while the top layer contain island-shape grey phases distributed in the continuous white phases. ©, Northeastern University. All right reserved.
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页码：1710 / 1714
页数：4
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共 13 条
  • [1] Sun Z.-P., Guo X.-P., Alloying effects on fracture toughness of both Nb-based solid solution alloys and Nb silicide-based alloys, Materials Review, 22, 4, pp. 79-83, (2008)
  • [2] Fernandes P.B., Coelh O.G.C., Ferreira F., Et al., Thermodynamic modeling of the Nb-Si system, Intermetallics, 10, 10, pp. 993-999, (2002)
  • [3] Bewlay B.P., Jackson M.R., Lipsitt H.A., Et al., Solidification processing of high temperature intermetallic eutectic-based alloys, Materials Science and Engineering A, 192, 2, pp. 534-543, (1995)
  • [4] Geng J., Tsakiropoulos P., Shao G.S., A study of the effects of Hf and Sn additions on the microstructure of Nb<sub>ss</sub>/Nb<sub>5</sub>Si<sub>3</sub> based in situ composites, Intermetallics, 15, 1, pp. 69-76, (2007)
  • [5] Saqib M., Srinivasan R., Weiss I., Oxidation behavior of Nb-based alloys by Al and Hf alloying, Scripta Metallurgieal et Material, 27, 4, pp. 425-433, (1992)
  • [6] Kim J.H., Mechanical properties and fracture behavior of an Nb<sub>ss</sub>/Nb<sub>5</sub>Si<sub>3</sub> in-situ composite modified by Mo and Hf alloying, Materials Science and Engineering A, 372, 3, pp. 137-146, (2004)
  • [7] Zelenitsas K., Tsakiropoulos P., Study of the role of Al and Cr additions in the microstructure of Nb-Ti-Si in situ composites, Intermetallics, 13, 10, pp. 1079-1095, (2005)
  • [8] Sha J.B., Hirai H., Tabaru T., Et al., Effect of C on microstrueture and high-temperature strength of Nb-Mo-Ti-Si in situ composites prepared by arc-melting and directional solidification, Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 34, 1, pp. 85-94, (2003)
  • [9] Guan P., Guo X.P., Ding X., Et al., Directionally solidified microstructure of an ultra-high temperature Nb-Si-Ti-Hf-Cr-Al alloy, Acta Metallurgical Sinica, 17, 4, pp. 450-456, (2004)
  • [10] Fu Y.M., Liu W., Zong W., Et al., Microstructure and room-temperature mechanical properties of Nb/Nb<sub>5</sub>Si<sub>3</sub> alloys fabricated by spark plasma sintering, Procedia Engineering, 27, pp. 1156-1161, (2012)
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