β型γ-TiAl合金中硼化物的取向及其对α相的影响  

Orientation Behavior of Borides in β-solidifying γ-TiAl Alloys and Its Effect on the Microstructure of theαPhase

作　　者：杨光 田普建[1] 葛正浩[1] 王义飞 杨肖肖 刘洁 刘延辉 宋文杰 YANG Guang;TIAN Pujian;GE Zhenghao;WANG Yifei;YANG Xiaoxiao;LIU Jie;LIU Yanhui;SONG Wenjie(College of Mechanical and Electrical Engineering,Shaanxi University of Science and Technology,Xi'an 710021,China)

机构地区：[1]陕西科技大学机电工程学院,西安710021

出　　处：《材料导报》2020年第8期113-118,共6页Materials Reports

基　　金：国家自然科学基金青年基金(51701107,51805308)。

摘　　要：本实验在β单相区分别对Ti-40Al-8Nb-0.5B及Ti-40Al-8Nb-1B合金进行了热变形,研究了两种合金中硼化物的取向行为及其对α相的影响。结果表明:热变形及硼含量显著影响硼化物的分布状态。未变形时,两种合金中的硼化物均为随机分布;变形后,Ti-40Al-8Nb-0.5B合金中硼化物呈现出强烈的[100]丝织构,而Ti-40Al-8Nb-1B合金中硼化物取向随机,这是由变形过程中硼化物的刚性旋转及其相互作用所造成的。经历β→α相变后,Ti-40Al-8Nb-0.5B合金α相呈现出<1120>和<1010>双丝织构,而Ti-40Al-8Nb-1B合金α相取向随机,这归因于硼化物、β相以及α相之间的组织遗传性。本研究可为β型γ-TiAl合金片层取向控制提供新的思路。In this work,hot deformation in the singleβphase region was performed to modify the distribution state of the borides in Ti-40Al-8Nb-0.5B and Ti-40Al-8Nb-1B alloys(at%),respectively.Special attention was paid to the orientation behavior of borides and its effect on the microstructure of theαphase.The results showed that the distribution state of the borides in these two alloys was significantly influenced by the hot defor-mation and boron content.The borides distributed randomly in the undeformed samples of Ti-40Al-8Nb-0.5B and Ti-40Al-8Nb-1B alloys,whereas the borides in the deformed Ti-40Al-8Nb-0.5B alloys presented a[100]fiber texture and the borides showed randomly distributed orientations in the deformed Ti-40Al-8Nb-1B alloys.This phenomenon is attributed to the rigid rotation of the borides and the interactions between the adjacent borides.After the subsequentβ→αtransformation,theαphase in Ti-40Al-8Nb-0.5B alloys exhibited a<1120>and<1010>double-fiber texture,whereas theαphase distributed randomly in Ti-40Al-8Nb-1B alloys,which is resulted from the microstructure heredity among theβphase,αphase and borides.The present study provides a new insight for the control of lamellar structure orientation inβ-solidifyingγ-TiAl alloys.

关 键 词：β型γ-TiAl合金 硼化物 取向 Α相 

分 类 号：TG111[金属学及工艺—物理冶金]