Contamination and Sinterability of Planetary-milled Alumina [Translated]†
Contamination of planetary milled alumina powder has been studied and correlated to sinterability. Ground powders contain Si and N contaminations derived from the grinding media and mill pot made of Si3N4. Strong shear stress generated during...
| Main Author: | |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Hosokawa Powder Technology Foundation
2014-05-01
|
| Series: | KONA Powder and Particle Journal |
| Online Access: | https://www.jstage.jst.go.jp/article/kona/13/0/13_1995020/_pdf/-char/en |
| _version_ | 1818459116230672384 |
|---|---|
| author | Osami Abe |
| author_facet | Osami Abe |
| author_sort | Osami Abe |
| collection | DOAJ |
| description | Contamination of planetary milled alumina powder has been studied and correlated to sinterability. Ground powders contain Si and N contaminations derived from the grinding media and mill pot made of Si3N4. Strong shear stress generated during planetary milling induces a mechanochemical reaction of worn-out Si3N4 with H2O contained in methanol used as a liquid medium forming hydrated SiO2 and provides an amorphous layer consisting of Si3N4, hydrated SiO2 and A12O3 on the surface of alumina particles. This suggests a possibility of applying planetary milling to surface modification of ceramic powders despite the problem of contamination. The surface layer containing the contaminations results in the formation of a mullite phase at the grain boundary during sintering. The low diffusion coefficient of mullite degrades sinterability even at a contamination as low as 400 ppm-Si. When the contamination increases to 0.5 mass%-Si, irregular grain growth and the formation of closed pores take place, suggesting the degradation of mechanical properties.† This report was originally printed in J. Soc. Powder Technology, Japan. 30(8), 548-555 (1993) in Japanese, before being translated into English by KONA Editorial Committee with the permission of the editorial committee of the Soc. Powder Technology, Japan. |
| first_indexed | 2024-12-14T23:09:14Z |
| format | Article |
| id | doaj.art-707b4f520829406e8a914bdf77b5261a |
| institution | Directory Open Access Journal |
| issn | 0288-4534 2187-5537 |
| language | English |
| last_indexed | 2024-12-14T23:09:14Z |
| publishDate | 2014-05-01 |
| publisher | Hosokawa Powder Technology Foundation |
| record_format | Article |
| series | KONA Powder and Particle Journal |
| spelling | doaj.art-707b4f520829406e8a914bdf77b5261a2022-12-21T22:44:14ZengHosokawa Powder Technology FoundationKONA Powder and Particle Journal0288-45342187-55372014-05-0113015916610.14356/kona.1995020konaContamination and Sinterability of Planetary-milled Alumina [Translated]†Osami Abe0Dept. of Mater. Sci., Faculty of Eng., Ibaraki Univ.Contamination of planetary milled alumina powder has been studied and correlated to sinterability. Ground powders contain Si and N contaminations derived from the grinding media and mill pot made of Si3N4. Strong shear stress generated during planetary milling induces a mechanochemical reaction of worn-out Si3N4 with H2O contained in methanol used as a liquid medium forming hydrated SiO2 and provides an amorphous layer consisting of Si3N4, hydrated SiO2 and A12O3 on the surface of alumina particles. This suggests a possibility of applying planetary milling to surface modification of ceramic powders despite the problem of contamination. The surface layer containing the contaminations results in the formation of a mullite phase at the grain boundary during sintering. The low diffusion coefficient of mullite degrades sinterability even at a contamination as low as 400 ppm-Si. When the contamination increases to 0.5 mass%-Si, irregular grain growth and the formation of closed pores take place, suggesting the degradation of mechanical properties.† This report was originally printed in J. Soc. Powder Technology, Japan. 30(8), 548-555 (1993) in Japanese, before being translated into English by KONA Editorial Committee with the permission of the editorial committee of the Soc. Powder Technology, Japan.https://www.jstage.jst.go.jp/article/kona/13/0/13_1995020/_pdf/-char/en |
| spellingShingle | Osami Abe Contamination and Sinterability of Planetary-milled Alumina [Translated]† KONA Powder and Particle Journal |
| title | Contamination and Sinterability of Planetary-milled Alumina [Translated]† |
| title_full | Contamination and Sinterability of Planetary-milled Alumina [Translated]† |
| title_fullStr | Contamination and Sinterability of Planetary-milled Alumina [Translated]† |
| title_full_unstemmed | Contamination and Sinterability of Planetary-milled Alumina [Translated]† |
| title_short | Contamination and Sinterability of Planetary-milled Alumina [Translated]† |
| title_sort | contamination and sinterability of planetary milled alumina translated † |
| url | https://www.jstage.jst.go.jp/article/kona/13/0/13_1995020/_pdf/-char/en |
| work_keys_str_mv | AT osamiabe contaminationandsinterabilityofplanetarymilledaluminatranslated |