Abstract
The microstructure of Al-Mg alloy composite reinforced with α-Si3N4 particles was investigated. Matrix grain boundaries were segregated with Si, N and O, and contain no secondary phases. On the other hand, matrix/reinforcement interfaces contain Mg2Si, MgO, and Al2MgO4. X-ray energy dispersive data also indicated a gradual variation of the N concentration across the reaction zone and enrichment of Mg at the interface between the matrix and the reaction zone. In situ TEM observation using a heating stage revealed incipient melting along grain boundaries and interfaces at 827 K. A liquid pocket was also observed at triple junctions. A good agreement in incipient melting temperature was obtained between TEM and DSC results. A possible role of the liquid phase in the superplasticity is discussed.
Original language | English |
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Pages (from-to) | 277-286 |
Number of pages | 10 |
Journal | Materials Science Forum |
Volume | 243-245 |
Publication status | Published - 1997 Jan 1 |
Keywords
- Grain boundary
- Interface
- Microstructure
- Segregation
- Superplasticity
ASJC Scopus subject areas
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering