Abstract
The MgB2 bulks were prepared using the spherical and scrap-like magnesium powders with the same purity (99.9%) and grain size (< 45 μm) as raw materials. The two kinds of magnesium powder were mixed with amorphous boron powder with a nominal stoichiometry of MgB2, then pressed into pellets under a pressure of 10 MPa, and sintered at 650°C, 700°C, 750°C and 800°C, respectively. The characteristics of holes for the sintered samples were described by using the immerged medium method. The results indicate that the porosities in the two kinds of MgB2 samples are similar. Their porosities increase with the increase of sintering temperature. The scanning electron microscope observation shows that the shapes and sizes of holes in sintered sample are associated with those of the raw Mg powder. Finally, the reason of hole formation for the Mg-B system during sintering process was analyzed based on the reaction model of Mg-B system.
| Original language | English |
|---|---|
| Pages (from-to) | 1260-1262 |
| Number of pages | 3 |
| Journal | Xiyou Jinshu Cailiao Yu Gongcheng/Rare Metal Materials and Engineering |
| Volume | 36 |
| Issue number | 7 |
| State | Published - Jul 2007 |
Keywords
- Hole formation
- MgB superconductor
- Reaction model