Effect of Trace Strontium Addition on Microstructure and Room Temperature Fracture Toughness of Nb-12Si-22Ti Alloys

Abstract:

The effect of strontium (Sr) addition (0.2 at.%) on the microstructure and mechanical properties of Nb-12Si-22Ti alloys were studied. Microstructure of the alloys was observed by scanning electron microscope, and their phase compositions were analyzed with X-ray diffraction and Electro-Probe Microanalyzer. The room temperature fracture toughness was measured. The results indicated that the phases of Nbss and Nb₃Si were presented in Nb-12Si-22Ti alloys. However, with the Al and Sr addition, the alloys were composed of Nbss and β-Nb₅Si₃. Compared with the Nb-12Si-22Ti alloys, the value of room temperature fracture toughness increased about 46% and 73% with the addition of Al and Sr alloy, respectively. The relationship between the microstructure and the mechanical properties was discussed.

• Periodical: Materials Science Forum (Volume 849)
• Pages: 603-608
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.849.603
• Online since: March 2016
• Authors: Mei Ling Wu, Feng Wei Guo, Ming Li, Ya Fang Han
• Keywords: Fracture Toughness, Microstructure, Nb-Si-Ti Alloy, Sr Addition

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