Mechanical Properties and Microstructure of Nb/Nb5Si3/Cr2Nb Alloys Prepared by Spark Plasma Sintering

Abstract:

Through the spark plasma sintering technology (SPS), the Nb/Nb₅Si₃/Cr₂Nb mixed powders with different volume ratios of 7:1:2 and 7:2:1 were sintered into ingots. The effects of three powder mixing methods on phase constitution, microstructure and room-temperature mechanical properties of the ternary Nb/Nb₅Si₃/Cr₂Nb alloys were investigated. The result shows that the method of dry mixing without ball milling is advantageous for toughness, the increase of SPS temperature decreases the toughness whereas improves the hardness. The stiffening Nb₅Si₃ and Cr₂Nb phases tend to form a continuous network, resulting in decrease of toughness. It is interesting that when the fractions of the Nb₅Si₃ phase larger than that of the Cr₂Nb phases, these strengthening phases prefer to appear in the form of network, which is detrimental for toughness.

• Periodical: Materials Science Forum (Volumes 747-748)
• Pages: 747-753
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.747-748.747
• Online since: February 2013
• Authors: Wei Zong, Wei Liu, Jiang Bo Sha
• Keywords: Nb/Nb5Si3/Cr2Nb Alloys, Spark Plasma Sintering (SPS)

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