Atomic investigation of alloying Cr, Ti, Y additions in a grain boundary of vanadium

详细信息    查看全文

• 作者：Pengbo Zhang^a ; ^b ; ^{zhangpb@dlmu.edu.cn" class="auth_mail" title="E-mail the corresponding author} ; Xiaojie Li^b ; Jijun Zhao^b ; Pengfei Zheng^c ; Jiming Chen^c
• 关键词：Grain boundary ; Alloying element ; Vanadium ; Embrittlement
• 刊名：Journal of Nuclear Materials
• 出版年：2016
• 出版时间：January 2016
• 年：2016
• 卷：468
• 期：Complete
• 页码：147-152
• 全文大小：2029 K

文摘

The effect of alloying additions (Cr, Ti and Y) in a vanadium (V) ∑3 (111) grain boundary (GB) is investigated by first-principles calculations. To determine site preference and segregation properties of Cr, Ti and Y in the GB and bulk, we calculate the formation energies and segregation energies for different interstitial and substitutional sites. Cr/Ti/Y atom prefers to segregate to the substitutional sites of the GB from bulk environment, whereas Cr segregation to GB is very weak. Based on the Rice and Wang's model, Cr acts as the GB cohesion, while Ti and Y are strong embrittlers. The analysis of atomic and electronic structures provides a reasonable expansion for the embrittlement behavior. Moreover, the effect of Cr, Ti and Y in the GB on solution of interstitial impurities C, N, O, H, and He are determined. The results show that Cr restrains solution of these impurities in the GB, while Ti tends to form Ti–N complex by absorbing N impurities and Y can absorbs O and He impurities. The present calculations are helpful for understanding the behavior of alloying Cr, Ti, Y additions at the grain boundary of vanadium.