摘要
测量Al,Si,Ti,Cr,Nb等纯元素以及Ti50Al50,Ti50Al48Cr2,Ti50Al48Nb2合金的符合正电子湮没辐射多普勒展宽谱和寿命谱,获得金属及合金中d电子和缺陷的信息。结果表明,二元TiAl合金的电子密度和3d电子的信号较低,晶界缺陷的开空间较大。在TiAl合金中加入Cr或Nb,合金中的d-d电子作用增强,基体和晶界处的电子密度均增加。Ti50Al48Cr2合金的多普勒展宽谱的d电子信号高于Ti50Al48Nb2合金。讨论了Cr和Nb对TiAl合金中缺陷和d-d电子相互作用的影响。
The positron lifetime and coincidence Doppler broadening spectra have been measured in pure Al, Si, Ti, Cr, Nb elements and Ti50Al50, Ti50Al48Cr2, Ti50Al48Nb2 alloys. It has been found that the 3d electron signal and the electron density for binary TiAI alloy are relative low due to the Ti 3d-Al 3p interactions. The addition of Cr and Nb atoms to TiAl alloy leads to the increase of electron densities in the bulk and grain boundaries simultaneously as well as the enhancement of d-d electron interactions. The d electron signal in the spectrum of Ti50Al48Cr2 alloy is higher than that of Ti50Al48Nb2 alloy. The effects of Cr and Nb on the d electrons of TiAI alloys have been discussed.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2009年第2期271-274,共4页
Rare Metal Materials and Engineering
基金
国家自然科学基金项目(50361002)
广西科学研究与技术开发计划项目(桂科攻0480004)
广西大学科学技术研究重点项目(2003ZD04)资助
