摘要
The present paper reported the phase stability and microstructures evolution of Nb-20Ti-16Si-xCr (x = 0~20at.%) in-situ composites as function of Cr addition. It was suggested that with the addition of Cr less than 7%, the silicide phase in as-cast Nb-20Ti-16Si alloy was Nb3Si. The silicides changed to be α-Nb5Si3 by the addition of Cr above 7%. It was found that annealing of 1300 ℃ for 100 h could result in the decomposition of Nb3Si to NbSS and α-Nb5Si3 in Cr containing Nb-20Ti-16Si based alloys by means of eutectoid reaction. Whereas in the case of alloy without Cr addition, the Nb3Si in Nb-20Ti-16Si alloy keep good stability during the high temperature annealing. The Cr additions larger than 5% in Nb-20Ti-16Si-xCr alloys could result in the formation of Cr-rich Laves phase. In addition, the influence of Cr addition on the room temperature fracture toughness of the alloys after annealing was reported.
The present paper reported the phase stability and microstructures evolution of Nb-20Ti-16Si-xCr (x = 0-20at.%) in-situ composites as function of Cr addition. It was suggested that with the addition of Cr less than 7%, the silicide phase in as-cast Nb-20Ti-16Si alloy was Nb3Si. The silicides changed to be a-NbsSi3 by the addition of Cr above 7%. It was found that annealing of 1300 ℃ for 100 h could result in the decomposition of Nb3Si to Nbss and a-Nb5Si3 in Cr containing Nb-20Ti-16Si based alloys by means of eutectoid reaction. Whereas in the case of alloy without Cr addition, the Nb3Si in Nb-20Ti-16Si alloy keep good stability during the high temperature annealing, The Cr additions larger than 5% in Nb-20Ti-16Si-xCr alloys could result in the formation of Cr-rich Laves phase. In addition, the influence of Cr addition on the room temperature fracture toughness of the alloys after annealing was reported.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2009年第A03期8-12,共5页
Rare Metal Materials and Engineering
基金
Aviation Science Foundation of China (Grant No 20061104)
关键词
微观结构
铌
硅化物
韧性
合金
Nb-Ti-Si, Cr, microstructure, fracture toughness