Evidence for excess vacancies at sliding grain boundaries during superplastic deformation

被引：17

作者：

Vetrano, JS ^{[1
]}

Simonen, EP ^{[1
]}

Bruemmer, SM ^{[1
]}

机构：

[1] Pacific NW Lab, Richland, WA 99352 USA

来源：

ACTA MATERIALIA | 1999年 / 47卷 / 15-16期

关键词：

transmission electron microscopy (TEM); aluminium alloys; grain boundaries; segregation; interfacial diffusion;

D O I：

10.1016/S1359-6454(99)00271-2

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Rapid quenching of AI-Mg alloys during superplastic deformation has revealed the presence of nano-scale cavities along many grain boundaries. They were observed only under deformation conditions where grain boundary sliding was the dominant mechanism. Fine-probe compositional measurements revealed that the cavity surface is enriched in Mg, and in situ heating in the transmission electron microscope demonstrated that they are not stable above 175 degrees C. Kinetic analysis of cavity formation during a quench concludes that the cavities did not exist during deformation but were formed as the sample cooled. It is proposed that these cavities are evidence for a localized excess of vacancies during grain boundary sliding. (C) 1999 Elsevier Science Ltd All rights reserved.

引用

页码：4125 / 4129

页数：5