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.
|ジャーナル||Materials Science Forum|
|出版ステータス||Published - 1997 1月 1|
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