Effect of chemical composition and heat treatment on microstructure and mechanical properties of Nb-xTi-16Si-3Cr-3Al-2Hf-yZr alloy

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:760

Article

Kang, Yongwang¹  Guo, Fengwei¹  Li, Ming¹ 

[1] AECC Beijing Inst Aeronaut Mat, Sci & Technol Adv High Temp Struct Mat Lab, Beijing 100095, Peoples R China

关键词: Ti;    Zr;    Nb-Si based material;    Microstructure;    Room temperature fracture toughness;    Hardness;   

DOI  :  10.1016/j.msea.2019.05.117

来源: Elsevier

【 摘 要 】

In this paper, four Nb-xTi-16Si-3Cr-3Al-2Hf-yZr (x + y = 20) alloys prepared by arc-melting furnace with non-consumable tungsten electrode, which was heat-treated at 1400 degrees C/50 h in argon atmosphere. The microstructures of the as-cast alloys and the heat-treated alloys were observed, and the room temperature fracture toughness and the hardness were tested. The results indicated that with the increase of Zr content, gamma-Nb5Si3 phase appeared in as-cast alloys with an increasing volume fraction. After heat treated, the microstructures of the alloys were finer, and the transformation from gamma-Nb(5)Si(3)to alpha-Nb5Si3 occurred. In addition, the room temperature fracture toughness and hardness of the heat-treated alloys are higher than those of as-cast alloys. For heat-treated alloys, the room temperature fracture toughness presented a slight downtrend followed by an up-trend with increase proportion of Zr, however the hardness was being improved. By contrast, for as-cast alloys the toughness and the hardness decreased.

【 授权许可】

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