Ti-22Al-25Nb合金B2相在α_2+B2相区长大行为的研究  

Study on B2 Grain Growth Behavior in α_2+B2 Phase of Ti-22Al-25Nb Alloy

作　　者：董志国 郑友平[2] 曾卫东[2] 薛晨[2] 梁晓波[3] Dong Zhiguo;Zheng Youping;Zeng Weidong;Xue Chen;Liang Xiaobo(AECC Shenyang Engine Research Institute,Shenyang 110015,China;State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,Xi’an 710072,China;Central Iron and Steel Research Institute,Beijing 100081,China)

机构地区：[1]中国航发沈阳发动机研究所,辽宁沈阳110015 [2]西北工业大学凝固技术国家重点实验室,陕西西安710072 [3]钢铁研究总院,北京100081

出　　处：《钛工业进展》2018年第2期13-16,共4页Titanium Industry Progress

基　　金：凝固技术国家重点实验室自主研究课题资助(153-ZH-2016)

摘　　要：研究了Ti-22Al-25Nb合金在α_2+B2两相区不同加热温度和不同保温时间下,B2相晶粒的长大行为。结果表明,Ti-22Al-25Nb合金在α_2+B2两相区加热时,基体B2相的晶粒尺寸随着加热温度的升高而增大,α_2相颗粒对B2相晶界迁移具有钉扎和阻碍作用,从而抑制了B2相基体晶粒的长大;随着保温时间的延长,基体B2相晶粒尺寸长大速度呈现先快后慢的规律,这主要是由于当加热时间较短时,B2相晶粒尺寸较小,晶界扩散的驱动力较大,晶粒长大速度快,而随着加热时间的延长,B2相晶粒尺寸不断增大,晶界迁移驱动力减小,晶粒长大速度放缓。The B2 grain growth behavior of Ti-22Al-25Nb alloy inα2+B2 two-phase region was studied at different temperatures and holding time.The result shows that the B2 grain size appears linear growth with the rising temperatures when Ti-22Al-25Nb alloy heat treated inα2+B2 phase.It is because theα2 particles can pin the B2 grain boundaries significantly and inhibit the B2 grain growth effectively.The B2 grain growth rate is fast firstly and then slow with prolonging the holding time.At the beginning of the heat treatment,B2 grains are generally fine and have high grain boundary diffusion driving force,which results in high B2 grain growth rates.Once the B2 grains grow up,the ratio of grain boundary to grain volume and driving force also decrease,then the grain growth rate decreases as well.

关 键 词：TI-22AL-25NB合金 晶粒长大 晶界钉扎 激活能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]