| Popis: |
The addition of a small amount of yttrium was found to improve ductility at intermediate temperatures or alleviate considerably what is called intermediate temperature embrittlement. The embrittlement in this case was considered to be related to the decrease in grain boundary strength. A trace impurity of sulfur was detected at a grain boundary fracture surface in a Cu-30%Zn alloy, while yttrium sulfides were detected in Y-bearing alloys. Thus, thus, the improvement in ductility was ascribable to the increase in grain boundary strength through the reduction of segregation of sulfur impurity. |
