Precipitation Process of The New Intermetallic γ1 Phase in Ti-Al-Nb Ternary System
High Nb containing TiAl alloys are often cited as a kind of prospective lightweight material for high temperature application. The novel intermetallic phase γ1(Ti4Nb3Al9), which formed from γ-TiAl phase,could elevate the service temperature. The development of new lightweight Ti-Al-Nb alloys having higher service temperature than high Nb containing TiAl alloys becomes possible. This paper investigated the effect of heat treatment on the precipitation of the γ1 phase in Nb-TiAl based intermetallic alloys. The results showed that as for nominal composition of γ1 alloy the homogenization temperature should be up to 1400℃. γ1 phase precipitates from the y phase matrix during the following furnace cooling process. Higher Nb and Al contents are favorable for the precipitation of γ1 phase. After appropriate heat treatment γ1 phase could form from the alloys with nominal composition of Ti53Al-(16-26)Nb,Ti-55Al-(22-28)Nb,Ti-56Al-(16-25)Nb(all at％). The angle between γ1 phases is about 120°,so in terms of morphologic characteristics the classical full lamellar(FL) is not favorable for the precipitation of γ1.
Intermetallics precipitation high Nb containing TiAl alloys
YiFan Hu Xiaojiao Zhang Junpin Lin Guoliang Chen
State Key Laboratory for Advanced Metals and Materials ,University of Science and Technology Beijing,Beijing 100083 , China
国际会议
The 12th World Conference Titanium(第十二届世界钛会 Ti-2011)
北京
英文
1515-1518
2011-06-19（万方平台首次上网日期，不代表论文的发表时间）