Grain boundary phase transformation in Cu-Co solid solutions

作者：Zhevnenko S N^*; Gershman E I

来源：Journal of Alloys and Compounds, 2012, 536: S554-S558.

DOI：10.1016/j.jallcom.2011.12.027

• Copper
• Cobalt
• Grain boundary
• Interface controlled diffusional creep

The present work examined the creep behavior of copper based solid solutions with cobalt at temperatures between 980 degrees C and 1080 degrees C and stresses lower than 0.2 MPa. The samples were made from 18 mu m foil and were formed into cylinders. After the pre-annealing at 1000 degrees C during about 30 h the samples had a parquet structure. The experiments were performed in the hydrogen atmosphere. New equipment was designed for these measurements.
The activation energy of pure copper creep was close to the activation energy of copper volume self-diffusion. Cu-Co solid solution creep rate was always lower than that of pure copper. It was shown that the creep activation energy in the relatively low temperature region was higher than in the high temperature region. The same behavior was typical for all studied solid solutions. The transition temperature was about 1030 degrees C.
It was proposed that such creep behavior was connected with grain boundary phase transformation and explanation was made in terms of interface controlled diffusional creep.

• 出版日期2012-9-25