摘要
通过非自耗电弧熔炼及氩气保护浇铸合成高Cr含量Ti-45Al-7Cr-2Nb合金。采用金相观察、X线衍射、扫描电镜及高温拉伸测试等方法研究不同结构的铸态合金在拉伸过程中的力学行为特征。研究结果表明:在室温至900℃及应变速率1×10-4 s-1时,全层状结构、近全层状结构以及近双态结构合金的强度都随温度的升高而下降,但全层状结构合金在室温和高温比其他2种结构合金表现出较高的强度;在900℃变形时,全层状结构合金的伸长率高最大,近双态结构次之,而近全层状结构则最小,这是由全层状结构所带来的界面强化(包括片层界面和畴界)所致。
Ti-45Al-7Cr-2Nb alloys with high Cr content were synthesized by non-consumable arc melting in argon atmosphere.Effect of microstructure on mechanical behavior of the as-cast alloy was investigated by optical microscope,scanning electron microscope（SEM）,X-ray diffraction and tensile testing at temperature of 25-900 ℃ and strain rate of 1×10-4 s-1.The results show that the strength of as-cast alloy with near fully lamellar（NFL）,fully lamellar（FL） and near duplex（NDP） structures decreases with the increase of tensile temperature.However,the strength of the FL structure alloy is more than those of the alloys with NFL and NDP,due to the interface strengthening of the FL structure,including lamellar interface and domain boundary.At 900 ℃,the elongation of the FL structure is higher than that of the structures of NFL and NDP.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第8期2278-2284,共7页
Journal of Central South University:Science and Technology
基金
粉末冶金国家重点实验室创新基金资助项目(PM2010)
湖南省科技计划专项(2009RS3025)
国家杰出青年科学基金资助项目(50825102)
中国博士后特别资助科学基金资助项目(200801348)
关键词
钛铝合金
热处理
显微组织
力学行为
TiAl alloy
heat treatment
microstructure
mechanical behavior
